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Identification of Transportation Planning Requirements in Federal Legislation




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                  Travel Model Improvement Program

The Department of Transportation, in cooperation with the
Environmental Protection Agency and the Department of Energy, has
embarked on a research program to respond to the requirements of
the Clean Air Act Amendments of 1990 and the Intermodal Surface
Transportation Efficiency Act of 1991.  This program addresses the
linkage of transportation to air quality, energy, economic growth,
land use and the overall quality of life.  The program addresses
both analytic tools and the integration of these tools into the
planning process to better support decision makers.  The program
has the following objectives:

1.   To increase the ability of existing travel forecasting
procedures to respond to emerging issues including; environmental
concerns, growth management, and lifestyle along with traditional
transportation issues,

2.   To redesign the travel forecasting process to reflect changes
in behavior, to respond to greater information needs placed on the
forecasting process and to take advantage of changes in data
collection technology, and

3.   To integrate the forecasting techniques into the decision
making process, providing better understanding of the effects of
transportation improvements and allowing decisionmakers in state
governments, local governments, transit operators, metropolitan
planning organizations and environmental agencies the capability of
making improved transportation decisions.

This program was funded through the Travel Model Improvement
Program.

     Further information about the Travel Model Improvement Program
     may be obtained by writing to:

                  Planning Support Branch (BEP-22)
                   Federal Highway Administration
                  U.S. Department of Transportation
                       400 Seventh Street, SW
                       Washington, D.C. 20590





Identification of
Transportation Planning
Data Requirements in
Federal Legislation


Final Report
July, 1994


Prepared by
Karla H. Karash
Carol Schweiger
EG&G Dynatrend
24 New England Executive Park
Burlington, Massachusetts 01803-5203

Prepared for
John A. Volpe National Transportation Systems
Center

Sponsored by
U.S. Department of Transportation 
     Federal Highway Administration 
     Federal Transit Administration 
     Office of the Secretary
U.S. Environmental Protection Agency

Distributed in Cooperation with
Technology Sharing Program
U.S. Department of Transportation
Washington, D.C. 20590


DOT-T-94-21





                          EXECUTIVE SUMMARY

This report identifies the new planning and associated data
collection requirements set forth in the Clean Air Act Amendments
(CAAA) of 1990 and the Intermodal Surface Transportation Efficiency
Act (ISTEA) of 1991.  Even though these requirements differ in
terms of their specificity, they promote the integration of
transportation and air quality planning processes.

While mobile source emissions have been declining over the past two
decades due to stricter auto emissions standards, increases in
vehicle miles traveled (VMT) and associated levels of congestion
are expected to reverse this favorable trend.  The CAAA of 1990
recognize the important role that transportation plays in
determining the air quality.  The CAAA mandates state
implementation plan (SIP) revisions which include emissions
estimates for current and future years, annual VMT reports and
forecasts based on transportation network models, demonstration of
attainment of the National Ambient Air Quality Standards (NAAQS),
and the implementation of transportation control measures (TCMS)
when milestones are not met.

The ISTEA represents the first transportation legislation that has
specific mandates with regard to achieving the objectives of the
Clean Air Act.  Recent implementing regulations for ISTEA set forth
requirements for both statewide and metropolitan area planning.  In
addition to requiring coordination of planning activities between
environmental agencies, transportation agencies, and other
interested parties, the regulations require an extensive public
process.  The metropolitan planning process must consider 15
different factors, and the statewide process must consider 23
different factors.  These factors include the interaction between
land use and development and transportation, the need to relieve
congestion; utilization of the management and monitoring systems to
identify transportation needs; the overall social, economic,
energy, and environmental effects of transportation, methods to
increase transit use; methods to increase the use of walking and
bicycles, and transportation system management (TSM) and other
investment strategies to make the most efficient use of existing
transportation facilities.

Other implementing regulations for ISTEA provide for the
establishment of six management and monitoring systems, which
together with a traffic monitoring system will provide better
information on the condition and use of existing transportation
facilities.  The congestion management system (CMS), in particular,
requires the identification and evaluation of strategies to improve
transportation system performance and reduce single-occupant
vehicle travel.

Conformity regulations link the transportation planning
requirements of ISTEA with the requirements of the CAAA.  These
regulations require that a transportation plan and transportation
improvement program (TIP) conform to a state implementation plan's
air quality objectives.  These objectives specifically address the
seventy and number of NAAQS violations, and the achievement of
NAAQS attainment as soon as possible.  Existing transportation
planning models will have to be significantly modified to satisfy
the requirements of the conformity regulations.





This report identifies the shortcomings of the existing set of
transportation planning models in terms of their ability to fulfill
the new requirements.  The four-step transportation modeling
process has been under development for four decades, but retains
essentially the same structure.  This process was established to
evaluate new regional transportation facilities, however, the new
planning requirements emphasize strategies which promote more
efficient use of the existing transportation facilities.  These
strategies include intermodalism, congestion management, and
various TCMs such as improved public transit, trip reduction
ordinances, traffic flow improvements, encouragement of non-
motorized uses, employer-based programs, etc.  Conformity
determinations include requirements that plans or projects provide
Carbon Monoxide (CO) violations, and for timely implementation of
TCMS, reduce localized carbon monoxide contribute to new violations
not contributions.

The degree of sophistication of the transportation planning process
differs from metropolitan planning organization (MPO) to MPO, and
there is a need to improve many existing models to the level of the
state-of-the-art.  The conformity regulations set forth minimum
standards, which include requirements that travel times be recycled
between traffic assignment and trip distribution, that model speeds
be based upon empirical observations, that travel be sensitive to
pricing, and that peak and off-peak travel times be provided.

While improvements in the four-step transportation modeling process
can accommodate some of the new requirements, other requirements
point out the need for alternative approaches or model structures. 
For example, the modeling process needs to be modified to provide
information on tripmaking by time of day, and to be sensitive to
transportation policies which may alter the time that tripmaking
occurs.  Trip-chaining behavior, along with its effect on work and
non-work tripmaking, VMT, and modal split must be also represented
in the models.  In addition, the level of detail represented by the
models must be increased in order to provide information on CO hot
spots, and VMT, trips, and speeds by small geographic areas.  The
models need to include variables relevant to tripmaking such as
demographic variables, urban design variables, and accessibility
measures.  Methods for accounting for walking and bicycling need to
be incorporated into the models.

The planning and data collection requirements of the CAAA and ISTEA
therefore reinforce the approach being undertaken by the Travel
Model Improvement Program.  Work needs to be done to bring current
practice to the state-of-the-art as well as to advance the state of
the art with research into new model structures and approaches.





                          TABLE OF CONTENTS

Section                                                         Page

1    INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . 1

     1.1  Purpose of this Report . . . . . . . . . . . . . . . . . 2
     1.2  Contents-of this Report. . . . . . . . . . . . . . . . . 2

2    REQUIREMENTS FOR TRANSPORTATION PLANNING IN
     FEDERAL LEGISLATION . . . . . . . . . . . . . . . . . . . .   3

     2.1  Clean Air Act Amendments of 1990 (CAAA)  . . . . . .     3
          2.1.1     Estimates of Emissions for Current Years and
                    Forecasted Years . . . . . . . . . . . . . . . 4
          2.1.2     Annual VMT Forecasts and Reports . . . . . . . 5
          2.1.3     Demonstration of Attainment of NAAQS . . . . . 6
          2.1.4     Milestone Compliance and Reasonable Further
                    Progress (RFP) . . . . . . . . . . . . . . . . 6
          2.1.5     Transportation Control Measures (TCMS) as
                    Needed to Meet the Milestones and NAAQS. . . . 7
          2.1.6     Contingency Measures When Milestones Are Not
                    Met. . . . . . . . . . . . . . . . . . . . . . 7

     2.2  Intermodal Surface Transportation Efficiency Act of 1991
          (ISTEA). . . . . . . . . . . . . . . . . . . . . . . . . 7
          2.2.1 Metropolitan Planning. . . . . . . . . . . . . . . 8
          2.2.2 Statewide Transportation Planning. . . . . . . . . 9
          2.2.3 Management and Monitoring Systems. . . . . . . . .10

     2.3  Conformity of Transportation Plans and Programs to Air
          Quality Implementation Plans . . . . . . . . . . . .    11

3    CAN THESE REQUIREMENTS BE SATISFIED BY THE CURRENT
     SET OF TRANSPORTATION PLANNING MODELS?                       14

     3.1  Why the Current Set of Models Are Inadequate . . . . . .14
          3.1.1 Model Shortcomings in Meeting the Requirements of
                the CAAA . . . . . . . . . . . . . . . . . . . . .14
          3.1.2 Model Shortcomings in Meeting the Requirements of
                the ISTEA. . . . . . . . . . . . . . . . . . . . .16
          3.1.3 Model Shortcomings in Meeting the Requirements of
                Conformity . . . . . . . . . . . . . . . . . . . .18

     3.2  Model Modifications. . . . . . . . . . . . . . . . . . .18

4    CONCLUSIONS . . . . . . . . . . . . . . . . . . . . . . . . .21

                                  i



APPENDIX A - HISTORICAL SUMMARY
OF TRANSPORTATION PLANNING . . . . . . . . . . . . . . . . . . . .23

     A-1  Brief History of Transportation Planning
     A-2  Tabular Summa of Transportation Planning History        28

APPENDIX B - ]DETAILED DESCRIPTION OF METROPOLITAN AND
STATE TRANSPORTATION STRATEGIES AND DATA COLLECTION
REQUIREMENTS                                                      41

     B-1  Clean Air Act Amendments of 1990 (CAAA)                 42

          B-1.1 Base Emissions Inventory, Periodic Inventories, and
                Protected Inventories                             43
          B-1.2 VMT Estimates                                     45
          B-1.3 Demonstration of Attainment of NAAQS              47
          B-1.4 Milestone Compliance and Reasonable Further
               Transportation Control Measures (TCMS) as Needed to
               Meet the Milestones and NAAQS . . . . . . . . . . .49
          B-1.6 Contingency Measures When Milestones Are Not Met .53

     B-2  Intermodal Surface Transportation Efficiency Act of 1991
          (ISTEA). . . . . . . . . . . . . . . . . . . . . . . . .53

          B-2.1 Metropolitan Planning. . . . . . . . . . . . . . .53
          B-2.2 Statewide Transportation Planning. . . . . . . . .59
          B-2.3 Management and Monitoring Systems. . . . . . . . .62

     B-3  Comfort of Transportation Plans and Programs to Air
          Quality Implementation Plans . . . . . . . . . . . . . .70

APPENDIX C - SUMMARY TABLES OF CURRENT PLANNING
REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . .76

APPENDIX D - GIS & IVHS AS MODELING TOOLS. . . . . . . . . . . . .92

APPENDIX E - LIST OF REFERENCES. . . . . . . . . . . . . . . . . .94

                                 ii
                         LIST OF ACRONYMS

AASHTO    American Association of State Highway and Transportation
          Officials
ADA       Americans with Disabilities Act of 1990
ADT       Average Daily Traffic
ATMS      Advanced Traffic Management Systems
BMS       Bridge Management System
BPR       Bureau of Public Roads
BTS       Bureau of Transportation Statistics
CAAA      Clean Air Act Amendments of 1990
CFR       Code of Federal Regulations
CMS       Congestion of Management System
CO        Carbon Monoxide
COG       Council of Governments
CVO       Commercial Vehicle Operations
DOE       U.S. Department of Energy
DOT       U.S. Department of Transportation
DVMT      Daily Vehicle Miles Traveled
EIA       Environmental Impact Statement
EKMA      Empirical Kinetic Modeling Approach
EO        Executive Order
EPA       Environment Protection Agency
FAA       Federal Aviation Administration
FAUA      Federal Aid Urbanized Area
FHWA      Federal Highway Administration
FTA       Federal Transit Administration
GIS       Geographic Information System
HOV       High-occupancy Vehicle
HPMS      Highway Performance Monitoring System
HPPM      Highway Planning Program Manual
HUD       Department of Housing and Urban Development
IMS       Intermodal Facilities and Systems Management
          System
IFR       Interim Final Rule
ISTEA     Intermodal Surface Transportation Efficiency Act of 1991
ISTEP     Intermodal System Transportation Evaluation Program
IVHS      Intelligent Vehicle-Highway Systems
MPO       Metropolitan Planning Organization
MTC       Metropolitan Transportation Commission (Oakland, CA)
NAA       Nonattainment areas
NAAQS     National Ambient Air Quality Standards
NARC      National Association of Regional Councils
NEPA      National Environmental Policy Act
NHS       National Highway System 
NPRM      Notice of Proposed Rulemaking
OST       Office of the Secretary of the U.S. Department of
          Transportation



                                 iii




                    LIST OF ACRONYMS (continued)

PMS       Pavement Management System
PPM       parts per million
PTMS      Public Transportation Facilities and Equipment Management
          System
RACM      Reasonably Available Control Measure
RACT      Reasonably Available Control Technology
RFP       Reasonable Further Progress
RPA       Regional Planning Agency
SCAG      Southern California Association of Governments
SIP       State Implementation Plan
SMS       Highway Safety Management System
STIP      Statewide Transportation Improvement Program
TCM       Transportation Control Measure
TCP       Transportation Control Plan
TDM       Transportation Demand Management
TIP       Transportation Improvement Program
TMAS      Transportation Management Areas
TMIP      Travel Model Improvement Program
TMS       Traffic Monitoring System
TSM       Transportation System Management
UMTA      Urban Mass Transportation Administration
UPWP      Unified Planning Work Program
USC       United States Code
VMT       Vehicles Miles Traveled
VOC       Volatile Organic Compound

                                 iv




1         INTRODUCTION

The Travel Model Improvement Program (TMIP) is a program Jointly
sponsored by the Office of the Secretary of Transportation (OST),
the Federal Highway Administration (FHWA), the Federal Transit
Administration (FTA), the Bureau of Transportation Statistics
(BTS), the Environmental Protection Agency (EPA), and the
Department of Energy (DOE).  This program is also being carried out
cooperatively with states, metropolitan planning organizations
(MEPOs), local governments, and private entities.  The purpose of
the TMIP is to remedy current transportation planning model
deficiencies in order to meet the requirements of the Clean Air Act
Amendments of 1990 (CAAA) as well as the Intermodal Surface
Transportation Efficiency Act of 1991 (ISTEA).

"The objectives of the Program are".

-    To increase the policy sensitivity of existing travel
     forecasting procedures and their ability to respond to
     emerging issues including environmental concerns, growth
     management, and changes in personal and household activity
     patterns, along with the traditional transportation issues,

-    To redesign the travel forecasting process to reflect today's
     traveler behavior, to respond to greater information needs
     placed on the forecasting process, and to take advantage of
     changes in data collection technology, and

-    To make travel forecasting model results more useful for
     decision makers."1

There are four tracks to the TMIP.  These are

Track A   Outreach to assist practitioners to improve their
          existing planning procedures to be in line with current
          good practice:

Track B   Near term improvements to assist MPOs and state DOTs to
          improve current practice to the state-of-the-art;

Track C   Longer term improvements including major research and
          development of new approaches to travel and land use
          forecasting; and

Track D   Data collection to "identify, design, and develop
          improved data collection procedures that will meet
          decision makers' current and future needs."2

__________________________
1 "Travel Model improvement Program," brochure from the Texas
Transportation Institute, 1994, p.2.
2 IBID, p.3.
                                  1
                                 
One of the elements of the last track is to identify the planning
strategies and requirements, and data collection requirements of
the Clean Air Act Amendments of 1990 (CAAA) and the Intermodal
Surface Transportation Efficiency Act of 1991 (ISTEA).

1.1  Purpose of this Report

This report presents a brief overview of the new planning
requirements in federal legislation and regulations related to the
CAAA and ISTEA, and the data that will be needed to fulfill those
requirements.  In addition, the report will provide insight into
the ability of the current set of transportation planning models to
address these requirements.

1.2   Contents of this Report

This report is divided into four sections.  Section 2 provides an
brief overview of current planning and data collection requirements
in the CAAA and ISTEA.  Section 3 provides a discussion about the
adequacy of the current set of transportation planning models for
addressing the planning requirements.  Section 4 presents the
conclusions of this effort.  Detailed descriptions of the history
of transportation planning, and the planning and data collection
requirements of the CAAA and ISTEA are provided as appendices. 
Appendix D discusses the potential for GIS and IVHS to improve
existing models and their associated data collection activities.  A
list of references is presented in Appendix E.

                                  2





2         REQUIREMENTS FOR TRANSPORTATION PLANNING IN FEDERAL
          LEGISLATION

Urban transportation planning was first mandated by the Federal-Aid
Highway Act of 1962.  This act established the "3C" planning
process - comprehensive, cooperative and continuing, and required
this type of planning as a condition for receiving Federal funds in
urbanized areas.  Further, it officially introduced the idea of
integrating land use with transportation, and declared that
planning be intermodal.

Currently, Federal legislation has mandated specific metropolitan
and statewide transportation planning requirements, has required
the establishment of six management systems to collect, maintain
and analyze transportation-related data, and has introduced strict
air quality planning and compliance requirements.  Even though the
planning requirements have changed  significantly since 1962, the
transportation planning models use methodologies which have 
changed little since the 1960s.

In order to identify the specific transportation planning and data
collection requirements from the aforementioned legislation, it was
necessary to perform in-depth research into all the pertinent
regulations and guideline documents that were written regarding the
legislation.  Detailed summaries of those requirements are included
in the appendices.  A briefer overview is presented below for each
relevant law or regulation.

2.1  Clean Air Act Amendments of 1990 (CAAA)

While mobile source emissions have been declining over the past two
decades due to stricter auto emissions standards, increases in
vehicle miles traveled (VMT) and associated levels of congestion
are expected to reverse this favorable trend.  The CAAA of 1990
recognize the important role that transportation plays in
determining the air quality.  Title II of that Act is entirely
devoted to provisions relating to mobile sources.

The transportation-related requirements of the CAAA are important
because the CAAA provide for sanctions related to transportation
program.   While sanctions could be applied the past, they were
triggered only by the failure to submit a state Implementation plan
(SIP).  Under the CAAA, sanctions can be triggered by either
failure to make submissions required under the act, or by
Environmental Protection Agency (EPA) disapproval of a SIP, or by
failure to implement any SIP provisions.  Because the CAAA reduced
the mandatory sanctions, highway funding restrictions could become
the primary sanction.3

The CAAA of 1990 define different categories of nonattainment areas
(NAA) for different air pollutants, depending upon the severity by
which the National Ambient Air Quality Standards (NAAQS) are
exceeded.  The CAAA then set up different schedules and
requirements for the 

______________________________

3    Gary Hawthorn, "Transportation Provisions in the Clean Air Act
Amendments of 1990," ITE Journal, April 1991, pp. 17-24.

                                  3




various NAA categories.  The worse the air pollution, the longer a
region has to comply with the NAAQS.  Also, the worse the air
pollution, the more stringent are the planning requirements and
measures mandated for compliance.  While there are NAAQS for many
different air pollutants, the ones most relevant to transportation
planning are those for ozone, and carbon monoxide (CO). 
Particulates (PM10) are relevant for a limited number of areas, but
planning requirements and models for these are much less well
defined.  NO2, is also a transportation-related pollutant, although
California's South Coast is the only NO2, NAA.  Both ozone and PM10
have precursors (volatile organic compounds and nitrogen oxides)
which must be considered for the purposes of SIP planning and
conformity.

The CAAA of 1990 set forth major transportation planning
requirements for the development of the SIPs and for conformity
determinations.  The SIPs must show how NAA will meet the NAAQS by
the attainment deadline, and adequate real progress in intermediate
future years.  The following discussion is based largely on the
NPRM for SIPS.4

The SIP revisions required by the CAAA include:

-    Estimates of emissions for current years and forecasted years
-    Annual VMT forecasts and reports;
-    Demonstration of attainment of the NAAQS,
-    Milestone compliance and reasonable further progress (RFP);
-    Transportation control measures (TCMS) as needed to meet the
     NAAQS; and
-    Contingency measures when milestones are not met.

The requirements listed above and the timing depend upon the type
of pollutant and the particular category of the NAA.

2.1.1 Estimates of Emissions for Current Years and Forecasted Years

All ozone NAA and CO NAA were required to submit by November 15,
1992, based emissions inventories of 1990 emissions from point
area, and mobile sources.  The contribution of mobile sources to
pollution in 1990 are determined by estimating VMT in 1990, and
applying emissions factors from the EPA MOBILE model.  MOBILE
estimates emissions levels bases upon the calendar year, ambient
temperatures during the peak ozone or CO season, fleet mix and
year, and several other factors.

_________________________________
4    "State Implementation Plans:, General Preamble for the
Implementation of Title I of the CAAA of 1990:, Proposed Rule," 57
FR 13498-13570 (April 16, 1992).

                                  4




Transportation related inputs to the MOBILE model include5

-    VMT by 8 vehicle types,

-    Annual mileage accumulation rate by 8 vehicle types;

-    Vehicle registration distribution by vehicle type and 25
     vehicle age categories;

-    Trip length distributions;

-    VMT by speed class (or by 12 roadway functional classes as a
     minimum -- six functional classes for rural and for urban
     areas),

-    VMT by time of day (as characterized by average speeds for the
     time period) by functional class.

-    Seasonal variation in VMT, vehicle mix, etc.

In addition to the base emission inventories, areas are required to
submit updated inventories every 3 years until the area reaches
attainment.  VMT estimates for these inventories would be computed
in the same way as for the base inventory, except that the Highway
Performance Monitoring System (HPMS) must be used for 1993 and
later VMT.

Target level inventories are also required for ozone NAA which must
come into attainment by November 15, 1996 or later.  In addition,
ozone NAA which must come into compliance after November 15, 1996
must provide target level inventories for each three year period
from 1996 until the attainment date.  The target inventories are
important, because control strategies must then be developed so
that actual emissions will meet the target levels.  The target
levels already account for tailpipe emissions improvements, so that
mobile source emissions reductions must come from VMT reductions,
trip reductions, or other means.

2.1.2   Annual VMT Forecasts and Reports

Annual actual VMT estimates and forecasts are required for all CO
NAA classified as Moderate, but with CO concentrations above 12.7
ppm.  In addition, VMT estimates and forecasts are required to
develop the emissions inventories both for ozone and CO as covered
above.  EPA has provided a guidance document for developing the VMT
estimates.6

_________________________________
5  "Procedures for Emission Inventory Preparation, Volume IV:
Mobile Sources," U.S. EPA, EPA-450/481-026d (Revised), 1992, pp.
13-61.
6  "Section 187 VMT Forecasting and Tracking Guidance," U.S. EPA,
January 1992.

                                  5



This document specifies that estimates of actual VMT for the NAA
are to be based upon the FHWA Highway Performance Monitoring System
(HPMS).7 In addition to the estimates of actual VMT, forecasts are
required of annual VMT from 1993 up until the year of attainment. 
Moderate CO NAA areas above 12.7 ppm are encouraged to use a travel
demand modeling process, but also may base VMT forecasts on
historical trends.  All Serious or higher ozone NAA can use the
guidance specified for Moderate CO NAA for forecasts to 1996. 
After 1996, the network based travel demand modeling process must
be used.

2.1.3 Demonstration of Attainment of NAAQS

The SIP revisions must demonstrate attainment of the NAAQS with a
schedule which depends upon the NAA category.  Demonstrating
attainment requires photochemical grid modeling for ozone NAAs
which are serious or worse, with inputs which include the projected
emissions inventories as described above.  An attainment
demonstration with photochemical grid modeling also provides target
emissions levels required for attainment and target VMT levels.

Photochemical grid modeling requires input on emissions for each
grid represented in the model.  These grids are typically 2km or
5km square.  This implies the needfor MT forecasts in the detailed
VMT categories required for the MOBILE model for each grid square
represented in the dispersion model.  In addition, hourly VMT may
be required for these models.8

2.1.4  Milestone Compliance and Reasonable Further Progress (RFP)

The CAAA set forth a series of intermediate milestones to be met by
NAA, with a schedule depending upon the pollutant and the non-
attainment category.  In the case of ozone NAA, the milestones are
specific emission reduction targets.  In the case of CO NAA, the
milestones are VMT targets.

In addition to the specific milestone requirements for different
pollutants, the CAAA specify a general requirement for RFP which is
annual incremental reductions in emissions.  However, rather than
make additional requirements for NAA for RFP, EPA has decided to
rely on existing requirements such as the periodic inventories and
other reports and certifications.9

_______________________
7    Highway Performance Monitoring System Field Manual, FHWA
Office of Highway Information Management, December 1987 updated
through April 20, 1990, FHWA Order M5600.  IA, ONM No. 2125-0028.

8    Peter R. Stopher, "Deficiencies in Travel Forecasting
Procedures Relative to the 1990 Clean Air Act Amendment
Requirements," prepared for Conference Session on Implications of
the 1990 Clean Air Act Amendments on Travel Demand Forecasting
Techniques, 1992 Transportation Research Board Annual Meeting,
December 1991.

9 "State Implementation Plans:, General Preamble for the
Implementation of Title I of the CAAA of 1990; Proposed Rule," 58
FR 13512 (April 16, 1992).

                                  6



2.1.5     Transportation Control Measures (TCMS) as Needed to Meet
          the Milestones and NAAQS

The SIP revisions must contain TCMs and other measures as necessary
for the NAA to meet the milestones and NAAQS.  The schedule and
types of requirements depend upon the category of the NAA.  Section
108(f) of the CAAA specify TCMs which include improved public
transit, HOV lanes, employer sponsored trip reduction programs,
programs to encourage bicycles and pedestrians, parking programs,
and so forth.

These SIP requirements have implications for transportation
planning.  VMT projections must be undertaken as previously
described.  Then TCM's need to be analyzed for their potential for
reducing VMT and emissions.  The SIP revisions must provide
evidence of adequate financial and human resources for each TCM,
and must describe the process of implementation, enforcement,
monitoring, and maintenance, where applicable.10  Where state
regulations or laws are required for TCM implementation, these
should be submitted as part of the SIP.

2.1.6     Contingency Measures When Milestones Are Not Met

The CAAA have many requirements for contingency measures should
milestones not be achieved in the case of ozone NAA, or VMT targets
not be achieved for CO NAA.  These measures are supposed to be
planned in advance, and submitted in implementable form in the 1992
or 1993 SIP revisions.  These measures are in addition to those
required to show compliance with the milestones.

2.2       Intermodal Surface Transportation Efficiency Act of 1991  
          (ISTEL)

The ISTEA represents the first transportation legislation that has
specific mandates with regard to achieving the objectives of the
Clean Air Act.  It establishes a Congestion Mitigation and Air
Quality Improvement Program to fund the implementation of projects
and programs that will contribute to achieving attainment of the
National Ambient Air Quality Standards (NAAQS).  In addition, ISTEA
specifies the designation of urbanized areas over 200,000
population as Transportation Management Areas (TMAs), each of which
will have a congestion management system that provides for the use
of travel demand reduction and operational management strategies
(see Section 2.2.3).

ISTEA also set forth requirements for metropolitan planning and
statewide planning.  The final rule for these requirements was
issued on October 28, 1993.

____________________________________
10   Transportation Control Measure Information Documents,
Cambridge Systematics, Inc., Report No. EPA 400-R-92-006, March
1992.

                                  7





2.2.1     Metropolitan Planning

The rule defines the metropolitan transportation plan as the
"official intermodal transportation plan that is developed and
adopted through the metropolitan transportation planning
for the metropolitan area."11

All MPOs serving an urbanized area of at least 50,000 are required
to submit a metropolitan transportation plan and a TIP which must
conform to SIPS.  A metropolitan plan must have a planning horizon
of 20 years; must broadly consider environmental and intermodal
issues and functions; must coordinate with TCM development in NAA;
and must incorporate uniform FHWA and FTA requirements for the
analysis of major metropolitan transportation investments.  The
plan must "Include both long- and short-range strategies/actions
that lead to the development of an integrated intermodal
metropolitan transportation system that facilitates the efficient
movement of people and goods." 12

The planning requirements set forth in the regulation include the
consideration of 15 factors covering a wide variety of
environmental, energy, transportation, land use economic issues. 
issues.  These factors include the need to relieve and prevent
traffic congestion and the consideration of the effect of
transportation on land use.

The majority of the data required to support the planning
requirements for development of the transportation plan will
eventually come from the management systems that are required to be
implemented by fiscal year 1995.  Out of the six systems required,
three have a direct relationship to the planning process:
Congestion Management System (CMS), Public Transportation
Facilities and Equipment Management System (PTMS), and Intermodal
Facilities and Systems Management System (IMS).  These management
systems are described later on in this section.

The development of the metropolitan TIP has a different focus than
the plan.  "The TIP must serve as the mechanism that focuses and
prioritizes the projects, establishes the relationships 
among projects, and notifies the public of project status for the
metropolitan area."13 The TIP is developed by the VTO in
cooperation with the state and public transit operators.  There
must be a reasonable opportunity for public comment on the TIP.

The TIP covers a three-year period (at a minimum), and must be
updated every two years.  It contains all projects proposed for
funding under Title 23 and the Federal Transit Act, and all
regionally significant projects in NAA.  The TIP must be consistent
with the transportation plan.  It must identify those projects
which are TCMs and give priority to the timely implementation of
TCMs contained in the applicable SIPS.  In NAA and maintenance
areas,

_________________________________

11    "Statewide Planning;, Metropolitan Planning; Rule," 58 FR
     58065 (October 28, 1993). 
12   "Statewide Planning; Metropolitan Planning; Rule.,, 58 FR
     58070 (October 28, 1993). 
13   "Statewide Planning; Metropolitan Planning; Rule," 58 FR 58061
     (October 28, 1993). 
                                  8

projects are to be specified in sufficient detail to permit air     
quality analysis in accordance with U.S. EPA conformity
requirements (40 CFR Part 51).  More specific conformity
requirements are covered in Section 2.3.

2.2.2     Statewide Transportation Planning

The requirements for statewide transportation planning are new with
the ISTEA.  These requirements include:

-    Data collection and analysis
-    Consideration of 23 factors in the statewide transportation
     planning process, including results of the management systems;
     TSM strategies; methods to reduce congestion; enhancing
     transit, bicycles, and pedestrians, the effect of
     transportation on land use; and so forth
-    Coordination of all planning activities relating to the
     development of the state transportation plan
-    Pro-active public involvement process
-    Development of a statewide transportation plan
-    Development of a statewide transportation improvement program
     (STIP)

A statewide transportation plan is due on January 1, 1995.  The
plan must be intermodal; cover a 20 year period; contain a plan for
bicycle transportation and pedestrian walkways, be coordinated with
the metropolitan transportation plans; contain short-range planning
studies, strategic planning, and/or policy studies, and contain
information on the availability of financial and other resources
needed to carry out the plan.

Requirements for the STIP are very similar to those for the TIP:

-    The STIP must include a priority list of transportation
     projects to be carried out in the first three years of the
     STIP.  Metropolitan planning area TIPs must be included,
     without modification, once approved by the MPO and the
     Governor, and found to conform by FHWA and FTA.

-    In NAA and maintenance areas, the STIP will contain only those
     transportation projects found to conform, or from programs
     that conform, to the conformity regulations.

-    The STIP must be consistent with the statewide plan.

-    The STIP must be financially constrained and must include
     information to demonstrate that funds can reasonably be
     expected to be available to implement the projects.

-    The STIP must contain all capital and non-capital
     transportation projects.  It must include projects requiring
     approvals by FHWA and FTA, even if these agencies are not
     providing funding.  For information purposes, the STIP should
     include all regionally significant transportation projects
     funded by other Federal agencies or by non-Federal funds.

                                  9





2.2.3      Management and Monitoring Systems14

Section 1034 of the ISTEA amended title 23 USC, Highways by adding
new section 303, Management Systems which requires the issuance of
regulations for State development, establishment, and
implementation of a system for managing each of the following;

-    Highway pavement of Federal-aid highways;
-    Bridges on and off Federal-aid highways;
-    Highway safety;
-    Congestion Management System (CMS),
-    Public Transit Management System (PTMS), and Intermodal
     Management System (IMS).

In addition to the six management systems the regulation specifies
a Traffic Monitoring System (TMS) to support the data required by
the six management systems.

The management systems must be developed and implemented in
cooperation with MPOs in metropolitan areas and with affected
agencies receiving assistance under the Federal Transit Act. 
States must be implementing each management system beginning in
Federal fiscal year 1995.  The FHWA and FTA agree that the
metropolitan and statewide transportation planning processes are
the appropriate forums for coordinating the outputs of the
management systems, as well as other transportation needs,
particularly since the legislation specifically requires the
outputs of the systems to be considered in these planning
processes.  The regulation states that to the extent possible, the
CMS, PTMS, and IMS are to be part of the transportation planning
processes in all metropolitan planning areas.  In TMAS, a CMS must
be part of the metropolitan planning process.

Each of the management systems will require data to define and
monitor the magnitude of the problems, identify needs, analyze
alternative solutions, and measure the effectiveness of the
implemented actions.  Some data needs, such as traffic volumes or
travel demand, may be common to all systems while other data will
be unique to the particular system.

The CMS will provide the most comprehensive data for planning,
since it is required to continuously collect and monitor data in
order to determine the duration and magnitude of traffic
congestion.  Also, it is required to identify and evaluate many of
the same strategies that must be identified in the plan as
addressing current and future transportation demand.  The PTMS will
identify and evaluate strategies related to public transportation. 
Beside a comprehensive inventory, the PTMS will collect data on the
number of vehicles and ridership for dedicated right-of-way at the
maximum load points in the peak direction and for the daily time
period.  The IMS expands the identification and evaluation of
strategies to intermodal facilities and efficiency.  Volume and
patterns of goods and people carried by intermodal will be
collected and monitored.


________________________________________
14 "Management and Monitoring Systems; Interim Final Rule," 58 FR
63442-63485 (December 1, 1993).

                                 10




The primary sources of data needed for these management systems
include, but are not limited to

-    Traffic counting programs     Surveys at activity centers
-    Travel time surveys           Parking inventories
-    Home interview surveys        Site impact studies
-    Employer surveys              Computerized signal systems
-    Vehicle occupancy counts      Cordon surveys
-    Screen line counts            On-board transit surveys
-    Travel behavior studies

The data for the TMS will be consistent with BPMS, and based on the
American Association of State Highway and Transportation Officials
(AASHTO) Guidelines for Traffic Data Programs15 and FHWA's Traffic
Monitoring Guide.16  These two guides suggest that the data to be
included in the TMS will result from continuous traffic counts,
short-term traffic monitoring, and vehicle occupancy monitoring. 
Typical data elements regarding traffic volume include, but are not
limited to:

-    Annual average daily traffic       Peak period volume
-    Design hourly volume               Diurnal distribution
-    Peak hour traffic percentage       Turning movements
-    Directional split                  Vehicle miles of travel


2.3  Conformity of Transportation Plans and Programs to Air Quality
Implementation Plans

The Clean Air Act [(Section 176(c)(4)(c)] requires each State to
submit an implementation plan revision which includes criteria and
procedures for assessing conformity.  "Conformity to an
implementation plan is defined in the Clean Air Act as conformity
to an implementation plan's purpose of eliminating or reducing the
severity and number of violations of the national ambient air
quality standards and achieving expeditious attainment of such
standards".17 The conformity regulations integrate the
transportation and air quality planning processes by requiring
interagency consultation in the development of transportation
plans, programs, and SIPS.

The final conformity rule sets forth additional requirements for
the content of the metropolitan transportation plan. 
Transportation plans adopted after January 1, 1995 in serious,
severe, or
______________________
15   AASHTO Guidelines for Traffic Data Programs, 1992, ISBN 1-
56051-054-4.

16   Traffic Monitoring Guide, Office of Highway Management,
October 1992, FHWA-PL-92-017.
17   "Air Quality Transportation Plans, Programs. and Projects;
Federal or State Implementation Plan Conformity Rule," 58 FR 62188
(November 24, 1993).


                                 11


extreme ozone NAA and in serious CO NAA must describe the
transportation system envisioned for future years called horizon
years.  For the horizon years, the plan must:

-    quantify and document the demographic and employment factors,
     including land use forecasts influencing expected
     transportation demand.

-    describe the regionally significant additions to the highway
     and transit network in sufficient detail to allow modeling of
     travel times under various volumes, and transit ridership. 
     Also, be specific enough to show a relationship between land
     use and the transportation system.

-    describe future transportation policies, requirements,
     services, and activities, including intermodal activities.

The final rule specifies the criteria for conformity which differ
by time period, by type of pollutant, and by the level of non-
attainment.  In addition to the criteria for conformity, the final
rule establishes a number of other criteria.  These are:

-    Use of the latest planning assumptions- These include the
     latest assumptions for current and future population,
     employment, travel, congestion, and background concentration
     of pollutants.  There is a requirement to discuss how transit
     operating policies have changed since the previous conformity
     determination, and there is a requirement to use reasonable
     assumptions about transit service, fares, and road and bridge
     tolls over time.  The conformity determination must use the
     latest information about TCM effectiveness.

-    Use of the latest emissions model.

-    The transportation plan, TIP, and projects which are not from
     a conforming plan or TIP must provide for the timely
     implementation of TCMS.

Lastly, the final rule establishes detailed criteria for
determining regional transportation-related emissions.  This
includes very specific modeling requirements after January 1, 1995
for serious, severe, and extreme ozone NAA and serious CO NAA.  The
modeling requirements include:18

-    The network-based model must be validated against ground
     counts for a base year that is not more than 10 years prior to
     the date of the conformity determination.

-    For peak-hour or peak-period traffic assignments, a capacity
     sensitive assignment methodology must be used;


___________________
18  IBID, p.62230-6223 1.

                                 12



-    Zone-to-zone travel times used to distribute trips between
     origin and destination pairs must be in reasonable agreement
     with the travel times resulting from the assignment of trips
     to network links.  These times should also be used for
     modeling mode splits if transit use is anticipated to be a
     significant factor,

-    Free-flow speeds on network links must be based on empirical
     observations;

-    Peak and off-peak travel demand and travel times must be
     provided;

-    Trip distribution and mode choice must be sensitive to
     pricing, where pricing is a significant factor;

-    The model must utilize and document a logical correspondence
     between the assumed scenario of land development and use, and
     the future transportation system for which emissions are being
     estimated, but reliance on a formal land-use model is not
     specifically required;

-    A dependence of trip generation on the accessibility of
     destinations via the transportation is not specifically
     required, unless the network model is capable of such system
     is not  determinations and the necessary information is
     available;

-    A dependence of regional economic and population growth on the
     accessibility of destinations via the transportation system is
     not specifically required, unless the network model is capable
     of such determinations and the necessary information is
     available;

-    HPMS estimates of VMT shall be considered the primary measure
     of VMT.  A factor or factors shall be develop to reconcile and
     calibrate the network-based model estimates of VMT in the base
     year of its validation to the BPMS estimates for the same
     period, and these factors shall be applied to model estimates
     of future VMT;

-    Reasonable methods shall be used to estimate NAA vehicle
     travel on off-network roadways within the urban transportation
     planning area, and on roadways outside the urban
     transportation planning area;

-    Reasonable methods in accordance with good practice must be
     used to estimate traffic speeds and delays in a manner that is
     sensitive to the estimated volume of travel on each roadway
     segment represented in network model; and

-    Ambient temperatures shall be consistent with those used to
     establish the emissions budget in the applicable
     implementation plan.

CO hot-spot analysis must be based on the applicable air quality
models, data bases and other requirements in 40 CFR Part 51,
Appendix W. Assumptions used in hot-spot analysis must be
consistent with the assumptions used in the regional emission
analysis.

                                 13





3         CAN THESE REQUIREMENTS BE SATISFIED BY THE CURRENT SET OF
          TRANSPORTATION PLANNING MODELS?

3.1   Why the Current Set of Models Are Inadequate

The information presented in this report illustrates the extensive
modeling and data collection requirements now required by federal
law and regulation.  These new requirements are difficult to meet
with the four-step modeling process, which has changed little over
the past thirty years.  This four-step process includes models for
trip generation, trip distribution, modal split, and network
assignment.  Land-use models may also be included as an additional
step prior to trip generation.19

Transportation planning models were developed to perform regional
highway analyses, and in particular, they were developed to analyze
the impact of major highway additions to the regional network.  The
CAAA and ISTEA focus on strategies which promote more efficient use
of the existing transportation network.  These include strategies
such as intermodalism, congestion management, and various TCMs such
as improved public transit, trip reduction ordinances, traffic flow
improvements, encouragement of non-motorized uses, employer-based
programs, etc.  Conformity determinations include requirements that
plans or projects provide for timely implementation of TCMS, reduce
localized CO violations, and not contribute to new violations. 
Transportation planning models lack the spatial and temporal
detail, the behavioral sensitivity, and sensitivity to alternative
modes of trip-making needed to provide the forecasts required by
the current regulations.  Following are some of the issues:

3.1.1     Model Shortcomings in Meeting the Requirements of the
          CAAA

The CAAA requires transportation system inputs for emissions
inventories, for CO hot-spot analyses, and for photochemical
modeling.  It also requires network based VMT estimates and
forecasts.  However, the CAAA requires much greater disaggregation
and detail than the urban transportation models have been designed
to provide.  For example:

-    Time-of-day situations, such as travel in the am peak, midday,
     and pm peak, are not well represented in the models.  Air
     quality, however, is very sensitive to time of day.  In
     determining base 1990 emissions inventories from mobile
     sources, EPA's MOBILE model requires the input of VMT by hour
     of the day.  Likewise, for forecasting VMT in CO NAA, the
     models need to distinguish peak and off-peak travel times.

______________________
19   See Peter R. Stopher and Amim H. Mevburg, Urban Transportation
Modeling and Planning., Lexington, MA: Lexington Books, D.C. Heath
and Co., 1975.

                                 14



-    Typical transportation planning model networks are not set up
     to accurately represent localized congestion problems which
     result in CO violations.  While the models can handle
     congestion on network links, CO hot spot analysis requires
     that such things as turning movements, intersection delays,
     and acceleration at on-ramps be represented.

-    Typical transportation planning model networks tend to be too
     coarsely defined to facilitate apportioning regional VMT for
     use in a photochemical grid model.  Currently, most existing
     transportation networks are based on traffic analysis zones
     and census tracts which are not at the level of detail
     required for the CAAA and conformity.  Where additional
     processing is required of the transportation model output to
     provide input to such a photochemical grid model, assumptions
     and approximations in this additional will introduce error
     into the emissions modeling.
           
-    Historically, transportation planning models did not validate
     link speeds.  These were used as interim variables only to
     produce link volumes.  In fact, once traffic assignment was
     completed, the model travel speeds were often found to be
     significantly different from the actual speeds.  Now, however,
     accurate representation of speeds is needed to properly
     forecast emissions.  In addition, accurate speeds are needed
     to account for the effects of congestion.  If the speeds in
     the model are too high, for example, a congestion induced
     shift in mode cannot be adequately represented.20

-    Although the CAAA requirements for attainment are driving the
     development of transportation plans and programs, the planning
     horizon and forecast years for the region often do not
     coincide with the required forecast years for the CAAA. 
     Therefore, extrapolations or interpretations of the
     transportation forecasts are needed as input to the emissions
     models.  These extrapolations or interpretations introduce
     assumptions and approximations that may not be appropriate.21

In addition to VMT, the number of trips, and particularly the
number of trips taken in cold start mode are critical for
determining emissions estimates.  Trip chaining (e.g., home to
daycare to work) is a growing phenomenon due partly to growth in
two-worker families.  Trip chaining affects the number of trips,
trip length, and the fraction of trips made in cold start mode. 
Models do not represent trip chaining, and therefore may over-
estimate the effect of employer based TCMs to reduce the use of
single occupancy vehicles by workers, for example22


______________________________

20   Maren L. Outwater and William Loudon, "Travel Demand
Forecasting Guidelines for the Federal and California Clean Air
Act," a paper prepared for presentation at the Transportation
Research Board, Annual Meeting, June 1994.

21   Greig Harvey & Elizabeth Deakin, "Toward Improved Regional
Transportation Modeling Practice (Revised), December 1991, p. 49.

22   Michael Replogle, "Improving Transportation Modeling for Air
Quality and Long-Range Planning," Environmental Defense Fund,
prepared for presentation to the Transportation Research Board 1993
Annual Meeting, p. 6.

                                 15





The CAAA also require the adoption of TCMs in some cases where they
are needed to meet the NAAOS.  These TCMs must be analyzed for
their potential to reduce VMT and emissions.  However, the typical
four-step modeling process is not sensitive to many of the TCMs
listed in Section 108(f) of the CAAA.

-    As mentioned above, time of day situations are not well
     represented in the models, But, the models need to analyze
     TCMs sensitive to time of day, such as programs to limit or
     restrict vehicle use in downtown areas during peak periods, or
     employer based programs to reduce single occupancy vehicles
     and permit flexible work schedules.

-    Several TCMs emphasize walking and biking.  However, most
     transportation models are concerned with vehicle trips rather
     than person trips, and thus ignore the non-motorized modes. 
     This problem is more important for short trips, which have the
     most potential to switch to walking or biking.  In addition,
     trip generation and distribution models do not typically
     include information on the attractiveness of the walking and
     biking environment or the proximity of housing and jobs or
     shopping which can affect the modal split for these modes. 
     Also, the models cannot handle changes in destinations which
     may result when there are mode shifts to non-motorized modes
     or when there are restrictions on vehicle access to points of
     the urbanized areas.

-    Several TCMs emphasize mass transit, and model shortcomings
     with respect to transit are similar to those for non-motorized
     modes.  Trip generation and distribution models do not
     typically include information on transit accessibility
     or levels of service.  Instead, highway travel times are used 
     to estimate trip distribution.  Transit use, however, depends
     upon urban structure (such as the density of development, the
     degree to which land uses are mixed, the connectivity of the
     roadways, and the proximity and levels of service of transit). 
     Transit use also depends upon the level of impedance to
     automobile travel (which can be affected by parking costs or
     limitations, or restrictions to automobile use in general),
     however the transportation models typically do not account for
     such variables.  Also, the share of trips made by park-and-
     ride and kiss-and-ride are not sensitive to factors such as
     changes in the proximity of jobs and housing to transit stops,
     changes in pedestrian and/or bicycle access, or park-and-ride
     lot expansion.

-    Mode choice models are not usually sensitive to factors
     related to auto occupancy, such as auto ownership.  Auto
     occupancy is an important factor related to several of the
     TCMs specified in the CAAA.

3.1.2 Model Shortcomings in Meeting the Requirements of the ISTEA

While the CAAA require the transportation modeling process to
produce much more detail than in the past, ISTEA requires that the
process consider many more factors than in the past.  The 15
factors to be considered for the metropolitan transportation plan
and the 23 factors to be considered for the state transportation
plan have implications for the transportation planning models:

                                 16




-    ISTEA mandates the reflection of a metropolitan area's
     comprehensive long range land use plan and metropolitan
     development objectives in the transportation plan.  Further,
     ISTEA mandates the consideration of the effect and consistency
     of transportation policy decisions on land use and
     development.  This implies the need to have transportation
     sensitive land use models, however, few such models are in
     use, and feedback from the transportation modeling process to
     land use models is typically not done.  Also, trip generation
     models tend to be insensitive to the jobs/housing balance
     which directly affects trip productions and attractions due to
     changes in residences and employment sites.  The current
     methods of computing trip productions and attractions can lead
     to underestimations and future year emissions and traffic
     congestion.

-    Mass transit, walking, and biking are to be emphasized.  As
     discussed above, the transportation modeling process does not
     usually handle these modes well

-    The social and economic effects of transportation decisions
     are to be considered.  This implies that the transportation
     modeling process should be more sensitive to demographics and
     social structure.  However, trip generation models are often
     not sensitive to alternative trip-making patterns due to
     variations in auto ownership, income, age of community,
     household size, and so forth.

The planning requirements for the Congestion Management System and
the Traffic Management system also place requirements on the
transportation models:

-    Traffic congestion greatly influences emissions.  However, in
     many transportation planning models, congestion has no effect
     on population distribution and employment forecasts due to the
     restricted sensitivity and lack of feedback between traffic
     assignment and land use modeling and trip generation.  In
     addition, the capacity constraints used in most models do not
     adequately degrade speeds at high levels of congestion, so
     that congested highway travel times are not considered in the
     mode choice part of the modeling process.

-    Strategies such as rideshare matching, telecommuting, and
     parking management are to be considered, but the models are
     typically not sensitive to policies which would encourage
     these options.

-    As mentioned previously, mode choice models are not usually
     sensitive to factors related to auto occupancy, such as auto
     ownership.  Auto occupancy is an important factor related to
     several of the congestion management strategies that must be
     considered in the development of a metropolitan transportation
     plan.

-    Congestion pricing is to be considered.  However, models
     sensitive only to time will not be sensitive to this option.

                                 17





-    IVHS technologies, such as motorist and transit information
     systems are to be considered.  The four-step modeling
     structure is not sensitive to a policy which would provide
     realtime information on traffic conditions to the traveler.

3.1.3     Model Shortcomings in Meeting the Requirements of
          Conformity

The conformity regulations recognize some of the typical
shortcomings of the transportation modeling process.  As stated
previously, these regulations require improved internal consistency
in the modeling process.  For example, free flow speeds in the
models are to be based on empirical observations.  Trip
distribution times are to be consistent with travel times resulting
from traffic assignment.  Trip distribution and mode choice must be
sensitive to pricing, where pricing is an important factor.  The
regulations require that the land-use and transportation system
interaction be considered, but do not require formal transportation
sensitive land-use models or the use of accessibility measures for
trip generation or regional growth.

3.2    Model Modifications

For the existing set of transportation planning models to be
responsive to the new federally mandated requirements, many changes
will have to be made to each element of the process. The Manual of
Regional Transportation Modeling Practice for Air /Quality
Analysis,23 sponsored by the National Association of Regional
Councils, provides guidance to MPOs for meeting the requirements of
the new legislation.  The degree of sophistication of the
transportation planning process differs from MTO to MPO, and there
is a need to improve many existing models in use around the country
to the level of the state-of-the-art.

However, it is important to note that even if the individual
elements of the modeling process are significantly modified to
respond to the newly-mandated planning requirements, there may well
be problems in the overall modeling framework that cannot be solved
unless the whole process and/or modeling structure is modified. 
Such problems result from attempting to handle such complicated
processes as time-of-day modeling, trip chaining, and a higher
level of detail (e.g., grid-based modeling) within the traditional
four-step process.

The shortcomings of the existing models relative to the newly-
legislated requirements indicate that significant changes are
needed in the models and potentially in the model structure to
accurately address these requirements.  The needed model
modifications are as follows:

-    Time of day modeling which adequately represents transit
     trips, traffic factors such as the length of the am peak and
     pm peak, and TCMs such as flexible work hours, must be
     included in the models.  This may require the development of
     time of day trip tables

___________________________
23   Manual of Regional Transportation Modeling Practice for Air
Quality Analysis, NARC, July 1993.

                                 18




immediately after trip generation, prior to the first use of any
network-derived data.24  Another approach might be to add a time of
day model as a fifth model in the process.

-    Representation of trip-chaining behavior must be included in
     the models.  Harvey and Deakin25 suggest that proper
     representation of trip chaining requires an accessibility
     variable for the home zone.

-    The transportation network must be represented in sufficient
     detail to allow network-based models to assist in determining
     conformity, particularly for CO.  In addition, the network
     must provide VMT for grid-based models to determine NAAOS
     attainment.  The use of GIS, in which a network can be
     described at a very detailed level26 using common geographic
     coordinates, could be helpful in fulfilling the requirements
     of the CAAA and the conformity regulations.

-    The models must be designed to accurately represent speeds on
     links.  And, as required by the conformity regulation, travel
     times used for trip distribution are to be consistent with
     travel times resulting from traffic assignment.  If recycling
     of travel times between network assignment and trip
     distribution is performed, the forecasts of trip destinations
     and modes can be made sensitive to levels of congestion, and
     trips will be shifted between transit/high-occupancy vehicles
     and single-occupant vehicles.

-    Travel costs should be included in the models.  In particular,
     parking costs, which may include both tangible cost and other
     factors such as parking capacity/accessibility should be
     included, since they can all be factors in mode choice.

-    Household income and other travel-sensitive variables such as
     household structure must be included in the models. 
     Demographic variables such as income significantly influence
     travel behavior and are needed to understand the socio-
     economic effects of transportation.

-    Bicycle and walk trips should be represented in the network
     and in mode choice models.   These modes could be easily added
     to the mode choice models, but the difficulty would be in the
     network representation, which would have to be quite detailed
     in order to accurately measure times and distances for walking
     and bicycle trips.

_________________________________
24   Peter R. Stopher, "Deficiencies in Travel Forecasting
Procedures Relative to the 1990 Clean Air Act Amendment
Requirements," op. cit., p. 23.

25   Greig Harvey and Elizabeth Deakin, "Toward Improved Regional
Transportation Modeling Practice," op. cit., pp. 27-28.

26   The term "very detailed level" refers to a level of detail
necessary to model non-motorized travel, such as bicycling or
walking.

                                 19

-    Automobile ownership modeling which is sensitive to work mode
     choice must be added to the models.  Automobile ownership is a
     major factor in mode choice and trip-making, but it is
     currently treated as an exogenous input which is often based
     on trend analysis. Automobile forecasting models should be
     sensitive to the potential of increases in transit, walk, and
     bicycle accessibility on household automobile ownership.

-    Transportation-sensitive land use models should be
     incorporated in the models.  Land use impacts on
     transportation have been difficult to quantify, primarily
     because issues such as the maturity of a particular region,
     and the balance of jobs and housing have not been represented
     in the models.  Land use models need to contain measures of
     accessibility for analysis zones which adequately reflect
     highway congestion, proximity to transit and transit level of
     service, and the environment for biking and walking.  In
     addition, the transportation models need to be sensitive to
     development issues.

                                 20





4         CONCLUSIONS

The landmark pieces of legislation discussed in this report provide
an opportunity for the linkage of the transportation and air
quality planning to evaluate NAAQS attainment and also promote
intermodalism and cost-effectiveness.  As discussed in Section 3,
these laws and rules will require significant modifications to the
transportation planning models, not only to fulfill the planning
requirements of ISTEA, but to provide input to emissions modeling
required by the CAAA and conformity regulations.

The CAAA mandates SIP revisions which include emissions estimates
for current and future years, annual VMT reports and forecasts
based on transportation network models, demonstration of attainment
of the NAAQS, and the implementation of TCMs when milestones are
not met.

Recent implementing regulations for ISTEA set forth requirements
for both statewide and metropolitan area planning.  In addition to
requiring coordination of planning activities between environmental
agencies, transportation agencies, and other interested parties,
the regulations require an extensive public process.  The
metropolitan planning process must consider 15 different factors,
and the statewide process must consider 23 different factors. 
These factors include the interaction between land use and
development and transportation; the need to relieve congestion;
utilization of the management and monitoring systems to identify
transportation needs; the overall social, economic, energy, and
environmental effects of transportation, methods to increase
transit use, methods to increase the use of walking and bicycles;
and TSM and other investment strategies to make the most efficient
use of existing transportation facilities.

Other implementing regulations for ISTEA provide for the
establishment of six management and monitoring systems, which
together with a traffic monitoring system will provide better
information on the condition and use of existing transportation
facilities.  The congestion management system (CMS), in particular,
requires the identification and evaluation of strategies to improve
transportation system performance and reduce single-occupant
vehicle travel.

Conformity regulations link the transportation planning
requirements of ISTEA with the requirements of the CAAA.  These
regulations require that a transportation plan and transportation
improvement program (TIP) conform to a state implementation plan's
air quality objectives.  These objectives specifically address the
severity and number of NAAQS as soon as possible.  Existing
transportation planning models will have to be significantly
modified to satisfy the requirements of the conformity regulations.

This report identifies the shortcomings of the existing set of
transportation planning models in terms of their ability to fulfill
the new requirements.  The four-step transportation modeling
process has been under development for four decades, but retains
essentially the same structure.  This process was established to
evaluate new regional transportation facilities,

                                 21





however, the new planning requirements emphasize strategies which
promote more efficient use of the existing transportation
facilities.  These include strategies such as intermodalism;
congestion management; and various TCMs such as improved public
transit, trip reduction ordinances, traffic flow improvements,
encouragement of non-motorized uses, employer-based programs. etc. 
Conformity determinations include requirements that plans or
projects provide for timely implementation of TCMS, reduce
localized CO violations, and not contribute to new violations.

The degree of sophistication of the transportation planning process
differs from MPO to MPO, and there is a need to improve many
existing models to the level of the state-of-the-art.  The
conformity regulations set forth minimum standards, which include
requirements that travel times be recycled between traffic
assignment and trip distribution, that model speeds be based upon
empirical observations, that travel be sensitive to pricing, and
that peak and off-peak travel times be provided.

While improvements in the four-step transportation modeling process
can accommodate some of the new requirements, other requirements
point out the need for alternative approaches or model structures. 
For example, the modeling process needs to be modified to provide
information on tripmaking by time of day, and to be sensitive to
transportation policies which may alter the time that tripmaking
occurs.  Trip-chaining behavior, along with its effect on work and
non-work tripmaking, VMT, and modal split must be also represented
in the models.  In addition, the level of detail represented by the
models must be increased in order to provide information on CO hot
spots, and VMT, trips, and speeds by small geographic areas.  The
models need to include variables relevant to tripmaking such as
demographic variables, urban design variables, and accessibility
measures.  Methods for accounting for walking and bicycling need to
be incorporated into the models.

The planning and data collection requirements of the CAAA and ISTEA
therefore reinforce the approach being undertaken by the Travel
Model Improvement Program.  Work needs to be done to bring current
practice to the state-of-the-art as well as to advance the state of
the art with research into new model structures and approaches.

                                 22





APPENDIX A - HISTORICAL SUMMARY
OF TRANSPORTATION PLANNING

                                 23




Urban transportation planning was first mandated by the Federal-Aid
Highway Act of 1962. The act established the "3C" planning
process - comprehensive, cooperative and continuing and required
this type of planning as a condition for receiving Federal funds in
urbanized areas.  Further, it officially introduced the idea of
integrating land use with transportation, and declared that
planning be intermodal.

Currently, Federal legislation has mandated specific metropolitan
and statewide transportation planning requirements, has required
the establishment of six management systems to collect, maintain
and analyze transportation-related data, and has introduced strict
air quality planning and compliance requirements.  Even though the
planning requirements have changed significantly since 1962, the
transportation planning models have not changed that much.  In
order to recognize the impact of thirty years of changes to the
planning requirements on the adequacy of the models, the following
subsections will briefly outline the history of transportation
planning in terms of Federal legislation.

A-1   Brief History of Transportation Planning

The history of transportation planning has been well documented,
particularly by Edward Weiner27.  A brief summary of the history,
presented below, highlights the legislation that has changed the
planning requirements over time.  A more detailed summary can be
found in the following table.

Although urban transportation planning was not mandated as part of
Federal funding requirements until the Federal-Aid Highway Act of
1962, there were several pieces of legislation before that which
established key planning organizations and programs.  Between 1916
and 1961, the following activities led up to the creation of the 3C
transportation planning process:

-    1916:     Bureau of Public Roads (BPR) created.

-    1921:     Federal-aid Highway System established, state
               highway departments organized, and state matching of
               Federal assistance required.

-    1934:     Discretionary highway planning and research program
               established.

-    1944:     Federal assistance for secondary and urban extension
               roads initiated and national system of interstate
               highways designated.

-    1953:     First funding provided for the U.S. Interstate
               Highway System.


27   Edward Weiner, Urban Transportation Planning in the United
     States: An Historical Overview, Office of Economics, Office of
     the Assistant Secretary for Policy and International Affairs,
     Office of the Secretary of Transportation, Revised Edition,
     November 1992, DOT-T-93-02.

                                 24





-    1956:     Funding created for national system of interstate
               and defense highways.

-    1961:     Program of loans and demonstrations for the
               construction of transit facilities and purchase of
               capital equipment created.

-    1961:     Use of Housing and Home Finance Agency comprehensive
               planning funds authorized for urban transportation
               planning.

Between 1962 and 1972, transportation planning requirements were
established through several pieces of legislation, were expanded to
include transit planning, guidance for planning was first issued,
and the integration of transportation planning and other planning
(environmental, land use, and air quality) was defined.  The
following list summarizes the legislative activities between 1962
and 1972:

-    1962:     3C urban transportation planning process mandated
               for receiving Federal funds.

-    1963:     3C planning process guidelines issued by the BPR
               (see discussion following these bullets).  Ten
               elements of the planning process were defined.

-    1964:     The Urban Mass Transportation Act created transit
               capital grants to public agencies, and the first
               national research and development program for
               transit was established.

-    1965:     Grants for comprehensive planning authorized to
               regional planning agencies (RPAS) and councils of
               government (COGs).  Department of Housing and Urban
               Development (HUD) created.

-    1966:     U.S. Department of Transportation (DOT) created,
               with the FHWA and the Federal Aviation
               Administration (FAA) as subordinate organizations.

-    1966:     The Metropolitan Development and Demonstration
               Cities Act required an area wide planning and review
               process for various Federal assistance programs,
               such as water and sewer grants, transit and highway
               assistance, urban renewal, etc.

-    1967:     FHWA consolidated previous urban transportation
               planning guidance in a Policy and Procedure
               Memorandum (PPM-50-9).

-    1968:     The Urban Mass Transportation Administration (UMTA)
               was transferred from to DOT.

-    1968:     FHWA issued an Instructional Memorandum (IM 50-4-
               68), "Operations Plans for Continuing Urban
               Transportation Planning," which maintained the
               responsiveness of planning to the needs of local
               areas.  Five elements were identified for a
               continued planning process: surveillance,
               reappraisal, service, procedural development and an
               annual report.

                                 25





-    1968:     The Intergovernmental Cooperation Act required the
               coordination of Federal programs with local
               governments, generally acting through RPAs or COGS.

-    1969:     The National Environmental Policy Act required a
               systematic interdisciplinary approach to planning as
               part of an environmental impact statement (EIS)
               process.

-    1970:     The CAAA of 1970 focused on traffic management as a
               remedy for air pollution control.  They also
               established the Environmental Protection Agency
               (EPA), specified emission standards, required the
               establishment of ambient air quality standards, and
               required State Implementation Plans (SIPS) and
               Transportation Control Plans (TCPs).

-    1972:     UMTA issued an External Operating Manual which
               included planning requirements for planning
               projects.  Appendix 2 of the Manual was entitled
               "Urban Mass Transportation Planning Requirements
               Guide," (UMTA Order 1000.2, dated August 22, 1972)
               which set forth the areawide planning requirements
               for the transit program.  These requirements were
               designed to be consistent with the 3C planning
               process.

The most significant documentation during this ten-year time frame
was the Highway Planning Program Manual (HPPM), originally issued
by the BPR and later updated by the FHWA.  Prior to the UMTA
External Operating Manual, the BPPM was the only technical
documentation and guidance available on the urban transportation
planning process.  Volume 8 of the HPPM was entitled "Urban
Transportation Planning," and contained the following chapters:

1.   General - Organization
II.  Use of Computers
111. Origin-Destination Surveys
IV.  Population Studies
V.   Economic Studies
VI.  Land Use
VII. Classification of Existing Street Use and Street Inventory
VIII.Development of Standards and Evaluation of Existing Traffic
     Services
IX.  Traffic Engineering Studies
X.   Public Transportation
XI.  Terminal Facilities
XII. Travel Forecasting (Trip Generation and Distribution)
XIII.Traffic Assignment
XIV. Developing the Transportation Plan
XV.  Plan Implementation
XVI. The Continuing Planning Process

Each chapter in the HPPM was originally written and updated between
September 1965 and August 1973.

                                 26





In 1975, UMTA and FHWA issued Joint highway and transit planning
regulations that unified the individual planning requirements of
FHWA and UMTA and superseded the operating procedures"28 mentioned
previously.  These regulations were the precursor to the current
requirements for metropolitan and statewide planning (to be
discussed in section 2.2). They included:

-    The development of a unified planning work program (UPWP)
     which describes all urban transportation and transportation-
     related planning activities anticipated during the next one to
     two-year period;

-    The development of a transportation plan, consisting of
     specific elements (Chapter I of title 23 and Chapter VI of
     title 49 of the Code of Federal Regulations (CFR), Part 450,
     Subpart A), including a long-range and transportation system
     management (TSM) elements,and

-    The development of a transportation improvement program (TIP).
     
Between 1977 and 1980, the following significant legislation
related to transportation planning requirements occurred:

-    1977:  The CAAA required that transportation plans, programs
and projects funded under title 23 or title 49 conform with State
or Federal air quality implementation plans.

-    1978:  The Surface Transportation Assistance Act added energy
conservation as a goal in the planning process.

-    1978:  Regulations integrating air quality planning and 3C
planning were issued.

-    1980:  Joint FHWA/UMTA Environmental Regulations were issued
that required a single set of environmental procedures for highway
and transit projects in order to produce a single EIS and
Alternatives Analysis document.

In 1981 and 1982, two Executive Orders (EOs) were issued by
President Reagan which reflected a national concern for the
complexity and burdensome nature of requirements and regulations29
Decentralization and intergovernmental coordination were the themes
in these two EOs (12291 and 12372).  EO 12291 "established
procedures for reviewing existing regulations and evaluating new
ones.  It required that a regulation have greater benefits to

____________________________________
28   "Planning Assistance and Standards: Urban Transportation
Planning;, Final Rule," 40 FR 42976 (September 17, 1975).

29   Edward Weiner, Urban Transportation Planning in the United
States: An Historical Overview, op. cit., p. 17 1.

                                 27





society than costs and that the approach used must maximize those
benefits.  All regulatory actions were to be based on a regulatory
impact analysis that assessed the benefits and costs.  The
objectives of EO 12372 were to foster an intergovernmental
partnership and strengthen federalism by relying on state and local
processes for intergovernmental coordination and review of
Federal financial assistance and direct Federal development.30

The impact of these EOs marked a turning point in the way
requirements and regulations were promulgated.  For transportation
planning, the first set of regulations that reflected this change
to more general requirements was issued in 1983.  Joint FHWA/UWTA
urban transportation planning regulations were revised to reflect
the reduction in the Federal government's involvement in urban
transportation planning.  These revised regulations "stated the
product or end that was required but left the details of the
process to the state and local agencies, so the regulations no
longer contained the elements of the process nor factors to
consider in conducting the process."31

Between this legislation and the present, all transportation
planning regulations and requirements continued to reflect a less-
specific nature, as follows:

-    1987:     The Surface Transportation and Uniform Relocation
     Assistance Act added a requirement to the planning process
     that involved the development of long-term financial plans for
     regional urban mass transit improvements.

-    1987:     Joint FHWA/UMTA Environmental Regulations were
     revised to provide more flexibility in the requirements for
     comprehensive environmental assessments.

Since 1990, there have been several significant pieces of
legislation and implementing regulations which mandate a new set of
planning and data collection requirements.  The legislation
includes the Clean Air Act Amendments of 1990 and the Intermodal
Surface Transportation Efficiency Act of 1991.  Detailed
descriptions of these requirements are included as Appendix B.

A-2    Tabular Summary of Transportation Planning History

A tabular summary of transportation planning history follows:

_____________________________

30   Ibid, p. 171 and 174.

31   Ibid, p. 185.

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                                 40




APPENDIX B - DETAILED DESCRIPTION OF
METROPOLITAN AND STATE TRANSPORTATION
STRATEGIES AND DATA COLLECTION
REQUIREMENTS

                                 41





In order to identify the specific transportation planning and data
collection requirements from recent federal legislation, it was
necessary to perform in-depth research into all the pertinent
regulations, NPRMS, and guideline documents that were written
regarding the legislation.  A complete list of references that were
consulted to prepare this report is shown in Appendix E.

A framework was developed in order to assess how the current set of
transportation planning models addresses the new requirements.  The
framework consists of the following information:

-    Dates of major planning requirements or documents;

-    Description of the legislative requirements for these
     documents,

-    Document required/document contents - this information
     describes the required document and its contents;

-    Planning Requirements - this information contains the planning
     that is accomplished in the preparation of the required
     document, and

-    Data Requirements - this information contains the data to be
     collected in the preparation of the required document to
     support the planning requirements.

Tables representing the framework for each required document are
included in Appendix C. Following are detailed descriptions of the
transportation planning and data collection requirements of current
legislation and the implementing regulations.

B-1 Clean Air Act Amendments of 1990 (CAAA)

The CAAA of 1990 define different categories of NAA for different
air pollutants, depending upon the severity by which the NAAQS are
exceeded.  The CAAA then sets up different schedules and
requirements for the various NAA categories.  The worse the air
pollution, the longer a region has to comply with the NAAQS.  Also,
the worse the air pollution, the more stringent are the planning
requirements and measures mandated for compliance.  While there are
NAAQS for many different air pollutants, the ones most relevant to
transportation planning are those for ozone, and CO.  Particulates
(PM10) are also relevant for a limited number of areas, but
planning requirements and models for these are much less well
defined. NO2, is also a transportation-related pollutant, although
California's South Coast is the only NO2, NAA.  Both ozone and PM10
have precursors (volatile organic compounds and nitrogen oxides)
which must be considered for the purposes of SIP planning and
conformity.

The following table shows the schedule for compliance for NAA for
ozone, CO, and PM10

                                 42





Pollutant  Severity      Design Value parts per   NAAQS Attainment
                              million (ppm)            Date

Ozone     Marginal       0.121 up to 0.138        Nov 15, 1993
                              over 1 hour
          Moderate       0.138 up to 0.160        Nov 15, 1996
                              over 1 hour
          Serious        0.160 up to 0.180        Nov 15, 1999
                              over 1 hour
          Severe(1)      0.180 up to 0.190        Nov 15, 2005
                              over 1 hour
          Severe(2)      0.190 up to 0.280        Nov 15, 2007  
                              over 1 hour
          Extreme        0.280 and above          Nov 15, 2010
                              over 1 hour

CO        Moderate(1)    9.1 to 12.7              Dec 31, 1995
                              over 8 hours
          Moderate (2)   12.7 through 16.4        Dec 31, 1995
                              over 8 hours
          Serious        16.5 and above           Dec  31,  2000
                              over 8 hours
PM10      Moderate       150 ug/M3 over           Dec  31,  1994
                              24 hours or
                         50 ug/m3 over a year

          Serious        If fall to reach         10 years after
                              attainment          reclassification


The CAAA of 1990 set forth major transportation planning
requirements for the development of the SIPs and for Conformity
determinations.  The SIPs must show how NAA will meet the NAAQS by
the attainment deadline, and adequate real progress in intermediate
future years.  Conformity determinations are required to show that
the Transportation plans, Transportation Improvement Programs, and
transportation projects are in line with the SIPS.  Conformity 
requirements will be addressed in Section B-3.
The SIP revisions required by the CAAA include:
-    Estimates of emissions for current years and forecasted years;
-    Annual VMT forecasts and reports;
-    Demonstration of attainment of the NAAQS;
-    Milestone compliance and reasonable further progress (RFP);
-    Special programs, including TCMs as needed to meet the NAAQS; 
     and
-    Contingency measures when milestones are not met.

The requirements listed above and the timing depend upon the type
of pollutant and the particular category of the NAA.  These items
are discussed in more detail below.

                                 43





B-1.1 Base Emissions Inventory, Periodic Inventories, and Projected
Inventories

Base Emissions Inventories:  All ozone NAA and CO NAA were required
to submit by November 15, 1992, base emissions inventories of 1990
emissions from point, area, and mobile sources.  The contribution
of mobile sources to pollution in 1990 are determined by estimating
VMT in 1990, and applying emissions factors from the EPA MOBILE
model.  MOBILE estimates emissions levels based upon the calendar
year, ambient temperatures during the peak ozone or CO season,
fleet mix and year, and several other factors.  A more detailed
discussion of VMT estimating is included in Section B-1.2 below,
and will not be repeated here.

Transportation related inputs to the MOBILE model include32

-    VMT by 8 vehicle types,

-    Annual mileage accumulation rate by 8 vehicle types--Vehicle
     registration distribution by vehicle type and 25 vehicle age
     categories;

-    Trip length distributions;

-    VMT by speed class (or by 12 roadway functional classes as a
     minimum -- six functional classes for rural and for urban
     areas);

-    VMT by time of day (as characterized by average speeds for the
     time period) by functional class.  Note that hourly VMT may be
     required for photochemical or other models;

-    VMT by the above categories by grid square for photochemical
     modeling purposes; and

-    Seasonal variation in VMT, vehicle mix, etc.

If data are not available on these factors, MOBILE contains
national default values.  However, for areas in Moderate and above
NAA, EPA expects states to develop and use their own specific
estimates of VMT by vehicle type and highway functional/volume
classes.

Periodic Inventories:  In addition to the base emission
inventories, areas are required to submit updated inventories every
3 years until the area reaches attainment.  The first periodic
inventories, due in 1995, cover actual emissions for the 1993 time
period.  VMT estimates for these inventories would be computed in
the same way as for the base inventory, except that



_____________________________
32 "Procedures for Emission Inventory Preparation, Volume IV:
Mobile Sources," U.S. EPA, EPA-450/481-026d (Revised), 1992, pp.
13-61, and Peter R. Stopher, "Deficiencies in Travel Forecasting
Procedures Relative to the 1990 Clean Air Act Amendment
Requirement," prepared for Conference Session on Implications of
the 1990 Clean Air Act Amendments on Travel Demand Forecasting
Techniques, 1992 TRB Annual Meeting, December 1991, p. 8.

                                 44





the Highway Performance Monitoring System (HPMS) system must be
used for 1993 and later VMT (see discussion under VMT below).

Adjusted Base Year Inventories and Target Level Inventories: For
all ozone NAA which are classified as Moderate or higher, the
November 15, 1992 SIP revision must contain adjusted base year
emissions inventories and target emissions inventories for 1996. 
These inventories are computed for 1996, but are based on the 1990
VMT estimates and MOBILE emissions factors for 1996.  The target
inventories are set at 85 percent of the adjusted base inventories
less various correction factors.  The target inventories are
important, because control strategies must then be developed so
that actual emissions will meet the target levels.  The target
levels already account for tailpipe emissions improvements, so that
mobile source emissions reductions must come from VMT reductions,
trip reductions, or other means.

For all Serious or higher ozone NAA, the November 15, 1994 SIP
revision should contain adjusted base year inventories and target
level inventories for each three year period from 1996 until the
attainment date.  Target level inventories would then be due in
1999, 2002, 2005, and 2008.  Again, the adjusted base year
inventories are based upon 1990 VMT, but use the target year
emissions factors from MOBILE.  Target inventories are set at
levels which are the previous milestone target less 9 percent of
the adjusted base year inventories (3 percent reduction per year
for 3 years) less a correction factor for fleet turnover.  Working
backwards from the target emissions inventories, the mobile portion
of the inventory can be determined along with VMT targets for each
milestone year.

The CAAA also calls for annual targets for emissions reductions for
volatile organic compounds (VOCS) and NOx.  These must be submitted
as part of the 1993 SIP revision for Moderate or higher ozone NAA.

B-1.2  VMT Estimates

Annual actual VMT estimates and forecasts are required for all CO
NAA classified as Moderate, but with CO concentrations above 12.7
ppm.  In addition, VMT estimates and forecasts are required to
develop the emissions inventories both for ozone and CO as covered
above.  EPA has provided a guidance document for developing the VMT
estimates.33

The first VMT forecast and report was due November 15, 1992 for CO
NAA with the 1992 SIP revision.  Estimates of actual VMT were to be
produced for 1990, and forecasts of VMT were to be produced for
1993 and each year thereafter prior to the attainment year.

Estimates of Actual VMT:  EPA specifies that estimates of actual
VMT for the NAA will be based upon the FHWA A HPMS.  The 1992 SIP
is supposed to contain a commitment by the state to sample each
HPMS facility class/volume group for VMT tracking purposes as of
June 1, 1993.

______________________________

33 " Section 187 VMT Forecasting and Tracking Guidance," U.S. EPA,
January 1992.
                                 45



The HPMS requires taking traffic counts for a sample of roadways by
facility type an d volume group.  Five urban highway facility types
are used, and 13 different volume classes.34  These counts consist
of 24 or 48 hour counts on each sample segment.  These are then
adjusted to annual averages based on day-of-week and seasonal
adjustment factors.  System mileage is computed depending upon the
sample segment length, the average daily traffic, and the expansion
factor for the segment type.

Note that in developing VMT for the emissions inventories, a
reverse process is required to provide VMT estimates for the peak
ozone or CO seasons, and for weekday hourly periods. These
estimates should use similar factors and assumptions as used to
expand daily counts to yearly VMT estimates for the HPMS.

One difficulty is that the HPMS system is set up to monitor the
Federal Aid Urbanized Area (FAUA), while VMT estimates for the SIP
may include areas outside the FAUA.  In addition, the SIP VMT
estimates should include local roadways.  Therefore, states need to
develop similar methods to HPMS to measure VMT information for
these areas.  Serious CO areas need to obtain EPA approval for such
"count-based" methods by June 30, 1994, and they must start using
these methods by January 1, 1995.

Annual VMT Forecasts: In addition to the estimates of actual VMT,
forecasts are required of annual VMT from 1993 up until the year of
attainment.  All Serious CO NAA should use a network based travel
demand modeling process.35 Moderate CO areas above 12.7 ppm are
encouraged to use a travel demand modeling process, but also may
base VMT forecasts on historical trends.  All Serious or higher
ozone NAA can use the guidance specified for Moderate CO NAA for
forecasts to 1996.  After 1996, the network based travel demand
modeling process must be used.

The requirements for the network based models are as follows36.

-    They should be validated against recent (1985 or later) ground
     counts for the region,

-    Forecasts with these models should be based upon forecasts of
     demographics, land-use, and transportation system
     characteristics.  Interpolation can be used to obtain values
     for future model target years, but these items should be
     forecast for at least I year within 5

_______________________________
34 " Procedures for Emission Inventory Preparation, Volume IV:
Mobile Sources," op. cit., p. 64.

35   The travel demand modeling process refers to the traditional
four-step process which has been developed over four decades.  See
Peter R. Stopher and Arnim H. Mevburg, Urban Transportation
Modeling and Planning, Lexington, MA: Lexington Books, D.C. Heath
and Co., 1975.

36  "Section 187 VMT Forecasting and Tracking Guidance," op. cit.,
pp. 20-21.
                                 46





years of the model target year.  Also, the latest forecast year
should be no earlier than the latest model target year, 

-    The models should be in equilibrium on each link, so that no
     link is loaded beyond its reasonable capacity;

-    The models should distinguish peak and off-peak travel times;

-    The models should recycle travel times as inputs until a self-
     consistent trip assignment among zones is achieved; and

-    The models should consider transit, where it is relevant.

Data requirements for the network based models are not discussed
further in the VMT guidance.  However, since output from the models
may well become the subject of litigation, considerable effort
should be expended to provide recent and accurate data for the
models 37. Also EPA has specified more modeling requirements as
part of the conformity regulation to be discussed in Section B-3.

B-1.3 Demonstration of Attainment of NAAQS

The SIP revisions must demonstrate attainment of the NAAQS with a
schedule which depends upon the NAA category.  Demonstrating
attainment requires photochemical grid modeling for ozone NAAs
which are serious or worse, with inputs which include the projected
emissions inventories as described above.  An attainment
demonstration with photochemical grid modeling also provides target
emissions levels required for attainment and target VMT levels. 
NAA which are moderate are permitted to use the empirical model,
city-specific Empirical Kinetic Modeling Approach (EKMA).


37   Although extensive direction has not been provided by EPA in
this guidance, EPA may have many suggestions for planning models. 
For example, Harvey and Deakin describe the EPA interaction with
the Metropolitan Transportation Commission (MTC) in conformity
findings: "EPA Region IX has closely scrutinized the technical
basis for MTC's (and others') conformity findings, but has shown a
willingness to tolerate, for the near term, what are perceived as
deficiencies in return for promises of future improvement in
modeling runs.  For example, the Southern California Association of
Governments (SCAG) could not respond to most of EPA's analysis
requests in the first interim conformity analyses, but did include:
(1) feeding back speeds through the trip distribution and mode
split steps until equilibrium was reached, (2) adding arterials to
the network, and (3) carrying out limited analyses of the effects
of employment and residence locations.  SCAG also agreed that
future conformity analyses will include: (1) incorporating the most
recent O/D survey and census data and projections, (2) addressing
the emission consequences of speeds above 55 M.P.H. in base and
forecast years, (3) assessing pricing measures - particularly toll
roads, (4) more comprehensive and consistent assessment of land use
interactions, (5) feedback of speeds through the trip generation
step, (6) improved TCM specification and quantification, and (7)
analysis of PM10." [From Greig Harvey and Elizabeth Deakin, "Toward
Improved Regional Transportation Modeling Practice," (Revised),
December 1991, p. 33.]

                                 47



For CO NAA with values greater than 12.7 ppm, the 1992 SIP revision
was required to contain a demonstration of attainment by December 3
1, 1995 for Moderate NAA and by December 31, 2000 for Serious NAA.

In the 1993 SIP revision, Moderate ozone NAA must demonstrate
attainment with the NAAQS by 1996.  There is also a 15 percent
reduction in emissions required for Moderate areas by 1996, which
is discussed below.  The 15 percent reduction for Moderate areas is
expected to be approximately what is required for attainment.  If
more reduction is required, Moderate areas are still required to
meet the NAAQS.  Serious or higher ozone NAA must demonstrate
attainment of the NAAQS in their 1994 SIP revision.

Photochemical grid modeling requires input on emissions for each
grid represented in the model.  These grids are typically 2km or
5km square.  This implies the need for VMT forecasts in the
detailed VMT categories required for the MOBILE model for each grid
square represented in the dispersion model.

An attainment demonstration by December 31, 1994 for PM10, NAA was
due with the 1991 SIP revision.  This demonstration was to include
air quality modeling, but a revised model was not available as of
July 1992.

B-1.4  Milestone Compliance and Reasonable Further Progress (RFP)

The CAAA set forth a series of intermediate milestones to be met by
NAA, with a schedule depending upon the pollutant and the non-
attainment category.  In the case of ozone NAA, the milestones are
specific emission reduction targets.  In the case of CO NAA, the
milestones are VMT targets.

All Moderate and higher ozone NAA must demonstrate in the 1993 SIP
revision a 15 percent reduction in emissions by 1996.  The target
levels are set by the target emissions inventories submitted with
the 1992 SIP revision as discussed above.  This reduction is in
addition to any emissions reductions already mandated at the time
of the CAAA with improved mobile source emissions reduction
technology.  Therefore, this demonstration requires other
reductions and transportation control measures, which can become
quite stringent where VMT is growing.

In addition to the 1996 15 percent reduction, Serious or higher
ozone NAA must submit with the 1994 SIP revision a "rate of
progress demonstration." This is a demonstration of a 3 percent
reduction in emissions on the average per year over each 3 year
period until attainment.  The milestone years are set every three
years from 1996 to the attainment date.  Target emissions
inventories are set as described above.  Special measures must be
included to bring mobile vehicle emissions into line with the
emissions inventory targets.


All CO NAA with values greater than 12.7 ppm were required to
submit with the 1992 SIP revision plans which contain forecasts of
VMT for each year before the year in which attainment is projected. 
These forecasts of VMT then serve as yearly VMT milestones.

                                 48





For PM10 NAA, the 1991 SIP revision was supposed to contain
quantitative milestones for emissions reductions which must be
achieved every 3 years.  If the demonstration of attainment by 1994
is impracticable, the plan must provide for expeditious
alternatives.

In addition to the specific milestone requirements for different
pollutants, the CAAA specify a general requirement for "reasonable
further progress" (RFP).  Section 171 of the Clean Air Act defines
RFP as such annual incremental reductions in emissions of the
relevant air pollutant as are required by this part or may
reasonably be required by the Administrator for the purpose of
ensuring attainment of the applicable NAAQS.  Section 172 of the
Clean Air Act then states that SIP provisions shall require RFP. 
However, rather than make additional requirements for NAA for RFP,
EPA has decided to rely on existing requirements such as the
periodic inventories and other reports and certifications38

B-1.5 Transportation Control Measures (TCMS) as Needed to Meet the
Milestones and NAAQS

The SIP revisions must contain TCMs as required to allow the NAA to
meet the milestones and NAAQS.  The schedule and types of
requirements depend upon the category of the NAA.  The worse the
NAA, the earlier the requirements for TCMS.

For PM10, NAA, transportation planning activities should include
measures to reduce PM10, in order to facilitate attainment of the
NAAQS.

Data requirements for PM10, analysis include:

-    Data on dust from paved and unpaved surfaces;

-    Data on motor vehicle exhaust from highway and off-highway
     sources;
     
-    Diesel vehicle exhaust and bus terminals, and

-    Re-entrained materials from traveled surfaces primarily paved
     and unpaved roads and open areas like parking lots.

Severe or higher ozone NAA must include in their 1992 SIP
revisions, TCMs to offset growth in emissions from growth in VMT
[Clean Air Act Section 182(d)(1)(A)].  Such areas should choose and
implement such measures as are specified in section 108(f) to the
extent needed to demonstrate attainment.  In addition, these areas
are required to submit a program for employer trip reduction to
reduce work trip VMT.


_______________________

38 "State Implementation Plans; General Preamble for the
Implementation of Title I of the CAAA of 1990, Proposed Rule," 57
FR 13512 (April 16, 1992).

                                 49





Serious CO NAA must also include TCMs for the purpose of reducing
CO emissions.  These areas must explain why any 108(f) measure was
not adopted.  The 108(f) measures are listed below39.

1.   Programs for improved public transit;

2.   Restriction of certain roads or lanes to, or construction of
     such roads;

3.   Employer-based transportation management plans, including
     incentives;

4.   Trip-reduction ordinances,

5.   Traffic flow improvement programs that achieve emission
     reductions"

6.   Fringe and transportation corridor parking facilities serving
     multiple occupancy vehicle programs or transit service,

7.   Programs to limit or restrict vehicle use in downtown areas or
     other areas of emission concentration particularly during
     periods of peak use;

8.   Programs for the provision of all forms of high-occupancy,
     shared-ride services;

9.   Programs to limit portions of road surfaces or certain
     sections of the metropolitan area to the use of non-motorized
     vehicles or pedestrian use, both as to time and place,

10.  Programs for secure bicycle storage facilities and other
     facilities, including bicycle lanes, for the convenience and
     protection of bicyclists, in both public and private areas;

11.  Programs to control extended idling of vehicles;

12.  Programs to reduce motor vehicle emissions, consistent with
     Title II, which are caused by extreme cold start conditions,

13.  Employer-sponsored programs to permit flexible work schedules;

14.  Programs and ordinances to facilitate non-automobile travel,
     provision and utilization of mass transit, and to generally
     reduce the need for single-occupant vehicle travel, as part of
     transportation planning and development efforts of a locality,
     including programs and ordinances applicable to new shopping
     centers, special events, and other centers of vehicle
     activity;


___________________________
39   Clean Air Act Amendments of 1990, Section 108(b), November 15,
1990.

                                 50





15.  Programs for new construction and major reconstructions of
paths, tracks or areas solely for the use by pedestrian or other
non-motorized means of transportation when economically feasible
and in the public interest, and

16.  Programs to encourage the voluntary removal from use and the
marketplace of pre-1980 model year light duty vehicles and pre-1980
model light duty trucks.

The 1993 SIP revision must contain TCMs and other measures as
necessary for Moderate or higher ozone NAA to achieve the 15
percent emissions reduction required by 1996.

The 1994 SIP revision must contain TCMs as required for Serious or
higher areas to achieve the 3 percent reduction in emissions per
year for each year following 1996 until attainment.  This SIP must
contain annual projections of TCM implementation and emissions
reductions.  Severe or higher ozone areas must submit their
employer compliance programs for employers of over 100 employees. 
Extreme ozone areas may submit TCM's applicable during periods of
heavy traffic that reduce the use of high polluting or heavy-duty
vehicles.

The 1996 SIP revision and each revision in 3 year intervals
following must contain a demonstration that "current aggregate
vehicle mileage, aggregate vehicle emissions, congestion levels,
and other relevant parameters are consistent with those used for
the area's demonstration of attainment.40  If not, the state has 18
months to submit a SIP revision which must include 108(f) measures
to bring projected emission levels into attainment.

These SIP requirements have implications for transportation
planning.  VMT projections must be undertaken as previously
described.  Then TCM's need to be analyzed for their potential for
reducing VMT and emissions.  The SIP revisions must provide
evidence of adequate financial and human resources for each TCM,
and must describe the process of implementation, enforcement,
monitoring and maintenance, where applicable.41  Where state
regulations or laws are required for TCM implementation, these
should be submitted as part of the SIP.

A difficulty for transportation planning is that the standard
transportation demand modeling process is not sensitive to many of
the TCMS.  Without improvements to the transportation modeling
process, many TCMs must be analyzed "off-line".  For example, MPOs
might estimate the effect of a program to create bicycle lanes by
assuming similar vehicle trip reductions to those experienced in 
other regions.  The trip reductions could then be factored

__________________
40 " State Implementation Plans; General Preamble for the
Implementation of Title I of the CAAA of 1990. Proposed Rule," 57
FR 13520 (April 16, 1993).

41   Cambridge Systematics, Inc., Transportation Control Measure
Information Documents, op. cit.

                                 51





into the transportation modeling process.  Current EPA guidance
provides excellent examples of TCM programs which could be used for
such an "off-line" approach.42

Although not spelled out in the TCM guidance, the data needs for
TCM analysis are extensive.  The following table lists TCM data
requirements as developed by Fleet, et.al. These data need to be
developed for each location of interest, for example central city,
suburbs, grid square, highway, intersection, transit route, or
whatever is appropriate for the analysis.



__________________________
42   Cambridge Systematics, Inc., Transportation Control Measure
Information Documents, op. cit.


                                 52



B-1.6 Contingency Measures When Milestones Are Not Met

The CAAA have many requirements for contingency measures should
milestones not be achieved in the case of ozone NAA, or VMT targets
not be achieved for CO NAA.  These measures are supposed to be
planned in advance, and submitted in implementable form in the SIP
revisions.  These measures are in addition to those required to
show compliance with the Milestones.

Contingency measures for ozone NAA are due with the 1992 or the
1993 SIP revision.  Moderate or above areas should submit
contingency plans which will provide additional emissions
reductions of up to 3 percent of the adjusted base year
inventory.43 In addition, the CAAA amendments suggest that Serious
or Severe areas may adopt economic incentive programs in the 1993
or 1994 SIP revisions where needed to meet the 15 percent emissions
reduction target in 1996.

When Serious or Severe areas fall to meet milestones, they have the
option of implementing economic incentive programs.  Extreme ozone
NAA with milestone failures, or which fall to submit demonstrations
are required to submit plan revisions with economic incentive
programs within 9 months of the failures.

CO NAA must provide contingency measures when actual VMT exceeds
forecasted VMT, or when updated forecasts of VMT exceed prior
forecasts.  For CO areas with design values above 12.7 ppm, these
contingency measures are due with the 1992 SIP revision.  Measures
needed for other Moderate CO areas to insure that the NAAQS are
achieved are due by November 15, 1993.  Contingency measures must
be adopted and enforceable.  These measures should be designed to
counteract the effect of 1 year's growth in VMT.44

The transportation planning implications of these contingency
measures are the same as those for the TCMs described above.

B-2  Intermodal Surface Transportation Efficiency Act of 1991
     (ISTEA)


B-2.1     Metropolitan Planning

The final rule for Metropolitan Planning was issued on October 28,
1993 and combined with Statewide Planning.  The rule defines the
metropolitan transportation plan as the "official intermodal
transportation plan that is developed and adopted through the
metropolitan transportation planning process for the metropolitan
planning area"45.  All MPOs serving an


____________________________
43  "State Implementation Plans; General Preamble for the
Implementation of Title I of the CAAA of 1990;, Proposed Rule," 57
FR 13511 (April 16, 1992).

44   lbid, p. 13532.

45   "Statewide Planning; Metropolitan Planning; Rule" 58 FR 58065
(October 28, 1993).

                                 53





urbanized area of at least 50,000 are required to submit a
metropolitan transportation plan and a TIP that satisfy both FHWA
(23 CFR Part 450) and FTA (49 CAR Part 613) requirements.  Further,
these plans and TIPs must conform to SIPs per EPA regulations (40
CAR Part 51) 46

Before describing the actual planning and data requirements for the
metropolitan plan, it is important to understand the content of the
plan.  The plan must have a 20-year horizon.  Also, it must
"Include both long- and short-range strategies/actions that lead to
the development of an integrated intermodal metropolitan
transportation system that facilitates the efficient movement of
people and goods."47

There are several considerations that must be included in the plan:

-    The identification of transportation demand of persons and
     goods;

-    The identification of adopted congestion management strategies
     that demonstrate a systematic approach in addressing current
     and future transportation demand.  These strategies may
     include:

     - Traffic operations          -  Ridesharing
     - Freight movement options    -  Pedestrian and bicycle        
                                       facilities
     - High occupancy vehicle (HOV) - Alternative work schedules
       treatments                   - Telecommuting

     - Public transportation improvements;

-    The identification of pedestrian walkway and bicycle
     transportation facilities;
     
-    The reflection of the results of the management systems,
     particularly the congestion management system (CMS);

-    The assessment of capital investment and other measures to
     preserve and most efficiently use the existing transportation
     system;

-    The description of existing and proposed transportation
     facilities in NAA to permit conformity determinations;

-    The multimodal evaluation of the transportation,
     socioeconomic, environmental, and financial impact of the
     overall plan;

______________________________

46   "Air Quality: Transportation Plans, Programs, and Projects;
Federal or State implementation Plan
Conformity, Rule", 58 FR 62188-62253 (November 24, 1993).

47  "Statewide Planning; Metropolitan Planning;, Rule," 58 FR 58075
(October 28, 1993).
                                 54





-    The reflection of the area's comprehensive long-range land use
     plan, metropolitan development objectives, and other local,
     state, or national goals including housing, employment,
     environmental, and energy goals and objectives.

-    The identification of proposed transportation enhancements,

-    The presentation of a financial plan that demonstrates the
     consistency of proposed transportation investments with known
     and project sources of revenue;

The planning requirements set forth in the Rule in order to prepare
a plan with the aforementioned considerations are not specific in
terms of the model(s) that should be used, or the data required. 
However, the elements of the planning, process are discussed and
can be summarized as follows:

-    The consideration of the following 15 factors:

     -    Preservation of existing transportation facilities.

     -    The consistency of transportation planning with
          applicable Federal, State, and local energy conservation
          programs, goals, and objectives.

     -    The need to relieve congestion and prevent congestion
          from occurring where it does not yet occur.  This
          includes a CMS in TMAs.

     -    The effect of transportation policy decisions and
          consistency with land use and development plans.

     -    The programming of expenditure on transportation
          enhancement activities as required in 23 USC 133.

     -    The effects of all transportation projects to be
          undertaken within the metropolitan area.

     -    International border crossings and access to ports,
          airports, intermodal transportation facilities, etc.

     -    The need for connectivity of roads within the
          metropolitan area with roads outside the metropolitan
          area.

     -    The transportation needs identified through use of the
          management systems required by 23 USC 303.

     -    Preservation of rights-of-way.

     -    Methods to enhance the efficient movement of freight.
                                 55



     -    Life-cycle cost in the design and engineering of bridges,
          tunnels, or pavement.

     -    Overall social, economic, energy, and environmental.
          effects of transportation. decisions.

     -    Methods to expand and enhance transit services and to
          increase the use of such services.

     -    Capital investments that would result in increased
          security in transit systems;

-    Early and continuing public involvement,
-    Consistency with Title VI of the Civil Rights Act;
-    The identification of actions necessary to comply with the
     Americans with Disabilities Act
-    Involvement by related and interested agencies and
     authorities; and
-    Involvement of local, state, and federal environment resource
     and permit agencies.

The majority of the data required to support the planning
requirements for development of the transportation plan will
eventually come from the management systems that are required to be
implemented by fiscal year 1995.  Out of the six systems required,
three have a direct relationship to the planning process: CMS,
Public Transportation Facilities and Equipment Management System
(PTMS), and Intermodal Facilities and Systems Management System
(IMS).  These will be discussed in more detail in Section B-2.3.

The development of the metropolitan TIP has a different focus than
the plan.  "The TIP must serve as the mechanism that focuses and
prioritizes the projects, establishes the relationship for the
metropolitan area."48 The TIP is developed by the MPO in
cooperation with the state and public transit operators. There
must be reasonable opportunity for public comment on the TIP.

The TIP covers a three-year period (at a minimum), and must be
updated every two years.  It contains the following:

-    All transportation projects within the metropolitan planning
     area proposed for funding under title 23 and the Federal
     Transit Act;

-    Only projects that are consistent with the transportation
     plan;

-    All regionally significant transportation49 projects for
     which FHWA or FTA approval is




_____________________
48  "Statewide Planning; Metropolitan Planning; Rule," 58 FR 58061
(October 28, 1993).

49   Regionally significant, in the case of transportation
facilities, means any facility with an arterial or higher
functional classification, plus any other facility that serves
regional travel needs (such as access to and from the area outside
of the region, to major activity centers in the region, or to
transportation

                                 56





     required whether or not the projects are to be funded with
     title 23 or Federal Transit Act funds: and

-    For informational purposes and air quality analysis in NAA and
     maintenance areas, all regionally significant projects to be
     funded with non-Federal funds.

For each project consistent with the aforementioned requirements,
the following data must be included in the TIP:

-    Sufficient descriptive material to identify the project or
     phase (in NAA and maintenance areas, enough detail must be
     included to allow air quality analysis in accordance with
     conformity requirements);

-    Estimated total cost;

-    The amount of Federal funds proposed to be obligated during
     each program year,

-    Proposed source of Federal and non-Federal funds,

-    Identification of the recipient/subrecipient and State and
     local agencies responsible for carrying out the project; and

-    In NAA and maintenance areas, identification of those projects
     which are TCMS.

-    Identification of projects to implement ADA required
     paratransit and key station plans.

As with the Metropolitan Plan, the planning requirements for the
TIP are not explicitly stated.  However, the process which is
required to produce the TIP is specified as having the following
steps:

-    Identify the criteria and process for prioritizing the
     implementation of transportation plan elements within the TIP;

-    Identify any changes in priorities from previous TIPS;

-    Identify those projects from a previous TIP that were
     implemented;

-    Identify those projects which experienced a significant delay
     in planned implementation;

-    In NAA and maintenance areas, describe the progress in
     implementing any required TCMS, including the reasons for any
     significant delays in the planned implementation; and

__________________________
terminals) and would normally be included in the modeling for the
transportation network.


                                 57




-    In NAA and maintenance areas, list projects from a previous
     TIP that were found to conform, and are now part of the base
     case for the purpose of conformity analysis.

B-2.2 Statewide Transportation Planning

As mentioned previously, the requirements for statewide
transportation planning are new with the ISTEA.  The Rule defines a
five step process as follows:

1.   Data collection and analysis.

2.   Consideration of the following factors:

     -    Results of the management systems required by 23 USC 303

     -    Federal, State or local energy use goals, objectives,
          programs, or requirements

     -    Strategies to incorporate bicycle transportation
          facilities and pedestrian walkways

     -    International border crossings and access to ports,
          airports, intermodal transportation facilities, etc.

     -    Transportation needs of areas outside of metropolitan
          planning areas

     -    Any metropolitan area plan

     -    Connectivity between metropolitan planning areas within
          the State and within metropolitan planning areas in other
          States

     -    Recreational travel and tourism

     -    Any State plan developed pursuant to the Federal Water
          Pollution Control Act

     -    TSM and investment strategies to make most efficient use
          of existing transportation facilities

     -    Overall social, economic, energy, and environmental
          effects of transportation decisions

     -    Methods to reduce congestion and prevent congestion from
          occurring where it does not yet occur

     -    Methods to expand and enhance transit services

     -    Effect of transportation decisions on land use and land
          development

                                 58





     -    Strategies for identifying and implementing
          transportation enhancements where appropriate throughout
          the state

     -    Use of innovative financing mechanisms

     -    Preservation of rights-of-way

     -    Long-range needs of the State transportation system for
          movement of persons and goods

     -    Methods to enhance the efficient movement of commercial
          motor vehicles

     -    Life-cycle costing in the design and engineering of
          bridges, tunnels, or pavements

     -    Coordination of metropolitan transportation plans and
          programs

     -    Investment strategies to improve adjoining State and
          local roads

     -    Concerns of Indian tribal governments

3.   Coordination of all planning activities relating to the
development of the state transportation plan.  The regulation
specifies 13 areas for coordination

4.   The development of a State transportation plan.

5.  The development of a State transportation improvement program
(STIP).

The statewide transportation plan is due on January 1, 1995.  The
plan will be developed cooperatively with the MPOs (consistent with
the metropolitan plans) and with Indian tribal government and the
Secretary of the Interior, if there is such an area in the State. 
The following requirements are presented in the regulation as to
the contents of the plan:

-    The plan must be intermodal and statewide in scope;

-    The plan must cover a period of at least 20 years;

-    The plan will contain a plan for bicycle transportation and
     pedestrian walkways in appropriate areas which are
     interconnected with other modes,

-    The plan shall be coordinated with the metropolitan
     transportation plan.
-    The plan will contain short-range planning studies, strategic
     planning and/or policy studies; and

                                 59





-    The plan will contain information on the availability of
     financial and other resources needed to carry out the plan.

Furthermore, the regulations specify that there shall be a
proactive public involvement process in the development of the plan
and STIP.

The data required to support the planning process includes;

-    Data from traffic data analysis including data from HPMS and
     the Traffic Monitoring System (TMS).

-    Data resulting from the management systems identifying
     statewide transportation needs.  These data are described in
     the section on the management systems, and include data on
     physical facilities and system performance.

-    Data on bicycle and pedestrian tripmaking

-    Data on recreational travel and tourism

-    Data on the social, economic, energy, and environmental
     effects of transportation decisions

-    Land use projection data including economic, demographic,
     environmental, growth management, and land use activities

-    Financial data for plans and programs

-    Data on existing and potential rights-of-ways for future
     transportation

-    Data on commercial motor vehicle efficiency

-    In addition to the statewide transportation plan, each state
     must develop a statewide transportation improvement program
     (STIP).  Requirements for the STIP are very similar to those
     for the TIP.  The contents of the STIP are specified as
     follows.

-    A priority list of transportation projects to be carried out
     in the first three years of the STIP must be included. 
     Metropolitan planning area TIPs must be included without
     modification after being approved by the MPO and the Governor,
     and being found to conform by FHWA and FTA.

-    The STIP must contain only projects consistent with the
     statewide plan.
     
-    In NAA and maintenance areas, the STIP will contain only those
     transportation projects found to conform, or from programs
     that conform, to the conformity regulations.

                                 60



-    The STIP must be financially constrained and must include
     information to demonstrate that funds can reasonably be
     expected to be available to implement the projects.

-    The STIP must contain all capital and non-capital
     transportation projects.

-    The STIP must contain all regionally significant
     transportation projects, even if not funded by FHWA or FTA.

For each project within a STIP, the following data are required:
     
-    Sufficient descriptive material to identify the project or
     phase,
-    Estimated total cost;
-    The amount of Federal funds proposed to be obligated during
     each program year,
-    Proposed category of Federal funds and source(s) of non-
     Federal funds, and
-    Identification of the agencies responsible for carrying out
     the project.

B-2.3 Management and Monitoring Systems50 

Section 1034 of the ISTEA amended title 23 USC, Highways by adding
new section 303, Management Systems which requires the issuance of
regulations for State development, establishment, and
implementation of a system for managing each of the following:

-    Highway pavement of Federal-aid highways;
-    Bridges on and off Federal-aid highways;
-    Highway safety;
-    CMS;
-    PTMS; and
-    IMS.

The systems must be developed and implemented in cooperation with
MPOs in metropolitan areas, with local officials in non-
metropolitan areas, with affected agencies receiving assistance
under the Federal Transit Act, and other agencies with
responsibility for the operation of affected transportation systems
or facilities.  States must be implementing each management system
beginning in Federal fiscal year 1995.  The FHWA and FTA agree that
the metropolitan and statewide transportation planning processes
are the appropriate forums for coordinating the outputs of the
management systems, as well as other transportation needs,
particularly since the legislation specifically requires the
outputs of the systems to be considered in these planning
processes.  In addition, it is proposed that, as appropriate, the
CMS, PTMS, and IMS be part of the transportation planning processes
in all metropolitan planning areas.  The CMS shall be part of the
metropolitan planning process in Transportation Management Areas
(TMAs).
_____________________________
50  "Management and Monitoring Systems; Interim Final Rule," 58 FR
63442-63485 (December 1, 1993).
                                 61


Each of the management systems will require data to define and
monitor the magnitude of the problems, identify needs, analyze
alternative solutions, and measure the effectiveness of the
implemented actions.  Some data needs, such as traffic volumes or
travel demand, may be common to all systems while other data will
be unique to the particular system.  The Interim Final Rule (IFR)
indicates the traffic monitoring system required by the
legislation, the FHWA's HPMS, and the data required by section 15
of the Federal Transit Act will be used by the FHWA and FTA to the
extent possible to meet their needs.

B-2.3.1   Pavement Management System (PMS)

Each State's PMS for the National Highway System (NHS) should be
based on AASHTO's Guidelines for Pavement Management Systems. The
analyses to be performed in the PMS include;.

-    Condition analysis (includes ride, distress, rutting and
     surface friction),

-    Performance analysis (includes pavement performance analysis
     and an estimate of the remaining service life);

-    Investment analysis (includes an estimate of total costs for
     present and projected conditions at the network-level and the
     development of project-level investment strategies with
     prioritized projects and preservation strategies using life-
     cycle costs);
     
-    Engineering analysis (includes the evaluation of design,
     construction, rehabilitation, materials, mix designs, and
     preventative maintenance as they relate to the performance of
     pavements), and 

-    Update (includes the annual evaluation and updating as
     necessary of the PMS based on the agency's current policies,
     engineering criteria, practices, and experience).

Data required by the PMS are:

-    Inventory - the physical pavement features, including the
     number of lanes, length, width, surface, type, functional
     classification, and shoulder information;

-    History - The project dates and types of construction,
     reconstruction, rehabilitation, and preventative maintenance;

-    Condition survey - the ride, distress, rutting, and surface
     friction;

-    Traffic volumes, vehicle classification, and load data; and

-    Database - the linking of all data files used in the PMS.  The
     database will also be the source for reporting pavement
     related information to FHWA for the HPMS.

                                 62





B-2.3.2   Bridge Management System (BMS)

The BMS is considered to be a decision support system that performs
analysis using mathematical models to predict deterioration and to
recommend alternative actions.  The BMS must be capable of
performing network level analysis and optimization, and will
include the following procedures to:

-    Predict the deterioration of bridge elements with and without
     intervening actions,

-    Identify feasible actions to improve bridge condition, safety,
     and service ability;

-    Estimate the cost of actions,

-    Estimate expected user cost savings for safety and service
     ability improvements;

-    Determine least-cost maintenance, repair, and rehabilitation
     strategies for bridge elements using life cycle cost analysis
     or a comparable procedure;

-    Perform multiperiod optimization;

-    Use feedback from actions taken to update prediction and cost
     models; and

-    Generate summaries and reports as needed for the planning and
     programming processes.

The BMS must contain a database and an ongoing program to collect
the data needed to support the BMS.  Data required to support this
analysis are:

-    Bridge inventory data
-    Bridge inspection data
-    Cost data
-    Supplemental data to support the analysis requirements of BMS
     (for example user costs including travel time, motor vehicle
     operating, and accident costs measured on site or estimated
     using models).

B-2.3.3   Highway Safety Management System (SMS)

The primary purpose of the SMS is to reduce the number and severity
of traffic crashes by ensuring that all opportunities to improve
highway safety are identified, implemented as appropriate, and
evaluated.

The five major planning areas to be addressed in the SMS are:

-    Coordination and integration of broad base safety programs
     such as motor carrier, corridor, and community-based traffic
     safety activities into a comprehensive management approach for
     highway safety;

                                 63





-    Identification and investigation of hazardous and potentially
     hazardous highway safety problems, roadway locations and
     features, including railroad-highway grade crossings, and the
     establishment of countermeasures and setting priorities to
     correct the identified hazards or potential hazards,

-    Insurance that safety in all highway transportation programs 
     and projects is considered early;

-    Identification of safety needs of special user groups such as
     older drivers, pedestrians, bicyclists, motorcyclists,
     commercial motor carriers, and hazardous material carriers, in
     the planning, design, construction and operation of highway
     systems; and

-    Routine maintenance and upgrade of safety hardware, highway
     elements and operational features.

The following issues must be addressed as appropriate for the five
major areas in the SMS:

-    The establishment of long and short term highway safety goals:

-    Identification and definition of the safety responsibilities;

-    Identification of disciplines involved in highway safety at
     the State and local level,

-    Assessment of multi-agency responsibilities and
     accountability;

-    Establishment of coordination, cooperation, and communication
     mechanism;

-    Data collection, maintenance and dissemination for identifying
     problems and determining improvement needs;

-    Analysis of available data and operational investigations, and
     comparisons of existing conditions and current standards to
     assess highway safety needs, select countermeasures, and set
     priorities;

-    Evaluation of the effectiveness of activities that relate to
     highway safety performance;

-    Development and implementation of public information and
     educational activities;

-    Identification of skills and resources needed to implement the
     State's highway safety activities and programs;

-    Identification of current and future training needs; and

-    Development of methods for monitoring and disseminating new
     technology and incorporating effective results.

                                 64





The data required by the SMS includes information pertaining to:

-    Crashes
-    Traffic (including number of trains at highway-rail crossings)
-    Pedestrians
-    Enforcement
-    Vehicles
-    Bicyclists
-    Drivers
-    Highways
-    Medical services

B-2.3.4 Traffic Congestion Management System (CMS)

Perhaps most closely related to the metropolitan and statewide
transportation planning processes, the CMS identifies and assesses
transportation system congestion.  The CMS will identify and
monitor areas within the State (metropolitan and rural) where
congestion is occurring or where there is potential for congestion,
and will determine the level of congestion.  The perception of
congestion is based on performance measures established
cooperatively by the state and affected MPOS, local agencies and
operators of major modes of transportation.  The CMS will be
capable of assessing the effects of physical improvements and/or
areawide transportation policy decisions on system performance.  It
will also be capable of providing an appropriate analysis of all
reasonable travel demand reduction and operational management
strategies for corridors where projects will significantly increase
capacity for SOVS.

The planning requirements for the CMS involve:

-    Identification and evaluation of strategies to improve
     transportation system performance. (There is an emphasis on
     strategies that reduce single-occupant vehicle travel.) These
     strategies would include, but not be limited to:

-    TDM measures, including carpooling, vanpooling, alternative
     work hours, telecommuting, and parking management

-    Traffic operations improvements, including intersection and
     roadway widening, channelization, traffic surveillance and
     control systems, motorist information systems, ramp metering,
     traffic control centers, and computerized signal systems

-    Measures to encourage HOV use, including public transit
     improvements, HOV lanes, HOV ramp bypass lanes, guaranteed
     ride home programs, and employer trip reduction ordinances

-    Public transit capital improvements, such as, exclusive
     rights-of-way, bus bypass ramps, park and ride, and mode
     change facilities, and paratransit services.

                                 65






     -    Public transit operational improvements, such as, service
          enhancements or expansion, traffic signal preemption,
          fare reduction, and transit information systems

     -    Measures to encourage modes such as facilities for
          bicycles, pedestrians, and ferry service

     -    Congestion pricing

     -    Growth management and activity center strategies

     -    Access management techniques

     -    Incident management

     -    Application of IVHS technologies and advanced public
          transportation system technologies

     -    The addition of general purpose lanes

-    For strategy implementation, identification of the schedule,
     responsibilities, and probable funding sources, and

-    Evaluation of the effectiveness of implemented strategies.

The data requirements for the CMS, although not specific, focus on
the continuous data collection and monitoring in order to determine
the duration and magnitude of congestion.  The actual data to be
collected will be based on the performance measures that are
selected to assess the congestion and estimate the change in
congestion when proposed strategies are implemented.  The table on
page 53 showing data needs for TCMs can also be used to describe
the data needed for the CMS.

B-2.3.5   Public Transportation Facilities and Equipment Management
System (PTMS)

The PTMS  is a systematic process for collecting and analyzing
information on the condition and cost of transportation facilities,
equipment and rolling stock (referred to hereafter as transit
assets).  PTMS will be capable of identifying and evaluating
strategies that impact current and future deficiencies.

The planning requirements of the PTMS include:

-    The identification and evaluation of proposed strategies and
     projects based upon the PTMS data collection and monitoring
     activities.  This effort should produce schedules for major
     maintenance or replacement, and estimated replacement costs.

                                 66

-    The identification of costs, funding sources, and priorities
     of proposed strategies and projects.

The data requirements for the PTMS are:

-    Base-year comprehensive inventory of transit assets, including
     age, condition, remaining useful life, and replacement cost;

-    Number of vehicles and ridership data for dedicated transit
     rights-of-way at maximum load points in the peak direction and
     for the daily time period;

B-2.3.6 Intermodal Facilities and Systems Management System (IMS)

The IMS is a systematic process for identifying intermodal
facilities, defining strategies to improve performance, and the
evaluation and implementation of these strategies.  Volume and
patterns of good will be collected and people carried by intermodal
transportation will be monitored.

The planning requirements of the IMS include:
-    The identification of intermodal facilities
-    The identification of performance measures to measure the
     efficiency of the facilities and systems moving people and
     goods.  Measures could include travel time, cost, volumes,
     origins and destinations, capacity, accidents, accessibility,
     perceived quantity, and transfer time.

Data collection and system monitoring
The data collection and monitoring in the IMS will include:
-    A base year inventory of physical and operating
     characteristics of intermodal facilities (operational
     characteristics include time, cost, capacity, and usage).

-    Survey of operational and physical characteristics of such
     facilities based upon performance measures established at the
     state and local level.

B-2.3.7    Traffic Monitoring System (TMS)

Even though it is not one of the six management systems, the TMS is
specified in the regulation to support the data required by the six
management systems.  The data from the
                                67


TMS will be consistent with the Highway Performance Monitoring
System (HPMS)51, and based on the American Association of State
Highway and Transportation Officials (AASHTO) Guidelines for
Traffic Data Programs52 and FHWA's Traffic Monitoring Guide53 
These two guides suggest that the data to be included in the TMS
will result from continuous traffic counts, short-term traffic
monitoring, and vehicle occupancy monitoring.  Typical data
elements regarding traffic volume include, but are not limited to:

-    Annual average daily traffic  -    Peak period volume
-    Design hourly volume          -    Diurnal distribution
-    Peak hour traffic percentage  -    Turning movements
-    Directional split             -    Vehicle miles of travel

The TMS must address the following elements:

-    Data precision to meet the needs of the data users,

-    Continuous counting operations to collect traffic volumes,
     vehicle classification, and vehicle weight;

-    Short-term traffic monitoring:

-    Count data on traffic volumes, vehicle classification and
     vehicle weight must be adjusted to reflect annual average
     conditions; and

-    Vehicle classification activities on the National Highway   
     System (NHS) shall ensure that no greater than every three
     years, every major system segment will be monitored to provide
     information on the numbers of trucks, buses, and total number
     of vehicles operating on an average day.

-    Vehicle occupancy monitoring, with data updated at a minimum
     of three years;

-    Field operations must include:

     -  Testing of data collection equipment
     -  Documentation of field operations
___________________________
51   FHWA, Highway Performance Monitoring System Field Manual,
Office of Highway Information Management, December 1987 updated
through April 20, 1990, FHWA Order M5600.  IA, OUB No. 2125-0028,
p. 1-2.

52   AASHTO Guidelines for Traffic Data Programs, 1992, ISBN 1-
56051-054-4.

53   FHWA, Traffic Monitoring Guide, Office of Highway Information
Management, October 1992, FHWA-PL-92-017.

                                 68


-    Source data retention, including the following data for each
     data collection session,

     -    Each value or values as collected during the session,
     -    Date on which each count was made,
     -    Hours during which the count took place,

-    Office factoring procedures, including:

-    Functional class-specific factors used to adjust data from
     short term monitoring sessions to estimates of average daily
     conditions shall be used to adjust for month, day of week,
     axle correction, and growth, and such factors shall be
     reviewed annually and updated at least every 3 years,

-    Document editing and adjusting procedures used by a State.

B-3  Conformity of Transportation Plans and Programs to Air Quality
Implementation Plans

The Clean Air Act [(Section 176(c)(4)(c)] requires each State to
submit an implementation plan revision which includes criteria and
procedures for assessing conformity.  "Conformity to an
implementation plan is defined in the Clean Air Act as conformity
to an implementation plan's purpose of eliminating or reducing the
severity and number of violations of the national ambient air
quality standards and achieving expeditious attainment of such
standards".54

Conformity is defined in Parts 51 and 93 of the CAR.  Part 51 sets
the conformity related requirements for the revision of the SIP. 
This revision is due by November 25, 1994.  Part 93 is very similar
and provides the conformity requirements for Federal agencies
effective as of December 27, 1993.  Conformity of existing
transportation plans must be re-determined within 18 months of the
final rule or by May 25, 1994 if not sooner.

The on-going schedule for conformity determinations is at least
every three years.  However, conformity determinations are
triggered by other events: when changes to transportation plans,
and/or TIPs are made; and when revisions to an implementation plan
are submitted (e.g., changes to a transportation-related emissions
budget, or changes to TCMS).  In the first case, changes to
transportation plans will require not only a new conformity
determination, but also a new conformity determination for the TIP. 
EPA is requiring that within six months of a transportation plan
amendment, the TIP be revised and a conformity determination made. 
In the second case, EPA is requiring that a new conformity
determination on the transportation plan be made in 18 months after
changes to an implementation plan.  In addition, FHWA and FTA
projects must also be found to conform before being approved or
funded.

_______________________
54   "Air Quality Transportation Plans, Programs, and Projects,
Federal or State implementation Plan Conformity; Rule," FR 58 62188
(November 24, 1993).

                                 69





The final rule requires consultation in the development of
transportation plans and programs and of SIPS.  Consultation is
required among transportation and air quality agencies.  In
addition, a proactive public process is required.  The following
organizations are to consult with each other during the plan
development process:

-    MPO's
     
-    State and local air quality planning agencies;

-    State and local transportation agencies;

-    Other organizations with responsibilities for developing,
     submitting, or implementing provision of an implementation
     plan required by the Clean Air Act;

-    Local or regional offices of the EPA;

-    Local or regional offices of the FHWA; and

-    Local or regional offices of the FTA.

The consultation procedures are to cover many transportation
planning processes, and specifically must include the process for
evaluating and choosing a model and methods to be used for hot spot
and regional emissions analysis.  In addition, the procedures are
to include a process for consulting on the design, schedule, and
funding of research and data collection efforts and transportation
model development by the MPO.

The final rule sets forth requirements for the content of the
transportation plan. Transportation plans adopted after January 1,
1995 in serious, severe, or extreme ozone NAA and in serious CO NAA
must describe the transportation system envisioned for future years
called horizon years.  For the horizon years, the plan must:

-    quantify and document the demographic and employment factors,
     including land use forecasts influencing expected
     transportation demand.

-    describe the regionally significant additions to the highway
     and transit network in sufficient detail to allow modeling of
     transit ridership and travel times under various volumes. 
     Also, be specific enough to show a relationship between land
     use and the transportation system.

-    describe future transportation policies, requirements,
     services, and activities, including intermodal activities.

The final rule specifies the criteria for conformity which differ
by time period, by type of pollutant, and by the level of non-
attainment.  The following table shows the time periods mentioned
in the rule.

                                 70



  TIME PERIOD            BEGINS ON                LASTS UNTIL

Interim Period-Phase I   Time prior to effective  Effective date 
                         date of final rule       of the final rule

Interim Period-PhaseII   Effective date of the    Submission to EPA
                         final rule               of the control 
                                                  strategy SIP
                                                  revision

Transitional Period      Submission to EPA of     EPA takes final 
                         the control strategy     approval or dis-
                         SIP revision             approval action
                                                  on the SIP revi-
                                                  sion

Control Strategy         EPA approves control     The area is rede-
Period                   strategy SIP revision    signated as an 
                                                  attainment area

Maintenance Period       The area is redesig-     Lasting 20 years
                         nated as an attainment   
                         area




The interim period has different conformity criteria and procedures
for regional and project-level analysis than those during the
control strategy and maintenance periods.  The control strategy and
maintenance periods have the same criteria and procedures.  The
transition period includes the requirements of the interim period
and the requirements of the control strategy and maintenance
periods.  The specific criteria can be summarized as follows:

-    In the interim and transition period, each FHWA/FTA project
     must eliminate or reduce the severity and number of localized
     CO violations in CO NAA.

-    In the interim and transition periods the transportation plan
     TIP, and projects not from a conforming transportation plan
     and TIP must contribute to emissions reductions in ozone and
     CO NAA.  They must not increase emissions in PM,, or NO, NAA. 
     Regional emissions analysis is required to show that these
     conditions are met.

-    In the transition, control strategy, and maintenance periods,
     regional transportation emissions from plans and TIPs need to
     be consistent with the SIP's transportation emissions budgets. 
     Likewise, a project not from a conforming transportation plan
     and TIP must be consistent with the motor vehicle emissions
     budgets.

In addition to the criteria for conformity, the final rule
establishes a number of other criteria.
These are:

-    Use of the latest planning assumptions- These include the
     latest assumptions for current and future population,
     employment, travel, congestion, and background concentration
     of pollutants.  There is a requirement to discuss how transit
     operating policies have changed since the previous conformity
     determination, and there is a requirement to use reasonable
     assumptions about transit service, fares, and road and bridge
     tolls over time.  The conformity determination must use the
     latest information about TCM effectiveness.

                                 71



-    Use of the latest emissions model.

-    The transportation plan, TIP, and projects which are not from
     a conforming plan or TIP must provide for the timely
     implementation of TCMS.

Lastly, the final rule establishes detailed criteria for
determining regional transportation-related emissions.  These
include very specific modeling requirements after January 1, 1995
for serious, severe, and extreme ozone NAA and serious CO NAA.  The
modeling requirements follow;55

-    The network-based model must be validated against ground
     counts for a base year that is not more than 10 years prior to
     the date of the conformity determination.

-    For peak-hour or peak-period traffic assignments, a capacity
     sensitive assignment methodology must be used;

-    Zone-to-zone travel times used to distribute trips between
     origin and destination pairs must be in reasonable agreement
     with the travel times resulting from the assignment of trips
     to network links.  These times should also be used for
     modeling mode splits if transit use is anticipated to be a
     significant factor;

-    Free-flow speeds on network links must be based on empirical
     observations;

-    Peak and off-peak travel demand and travel times must be
     provided;

-    Trip distribution and mode choice must be sensitive to
     pricing, where pricing is a significant factor; 

-    The model must utilize and document a logical correspondence
     between the assumed scenario of land development and use, and
     the future transportation system for which emissions are being
     estimated, but reliance on a formal land-use model is not
     specifically required;

-    A dependence of trip generation on the accessibility of
     destinations via the transportation specifically required,
     unless the network model is capable of such system is not
     determinations and the necessary information is available;

-    A dependence of regional economic and population growth on the
     accessibility of destinations via the transportation system is 
     not specifically required, unless the network model is     
     capable of such determinations and the necessary information
     is available; and


__________________
55   IBID, p.62230-6223 1.

                                 72


-    Consideration of emissions increases from construction-related
     congestion is not specifically required.

Additional requirements of the emissions analysis are:

-    HPMS estimates of VMT shall be considered the primary measure
     of VMT.  A factor or factors shall be develop to reconcile and
     calibrate the network-based model estimates of VMT in the base
     year of its validation to the HPMS estimates for the same
     period, and these factors shall be applied to model estimates
     of future VMT.  Departure from these procedures is permitted
     with the concurrence of DOT and EPA.

-    Reasonable methods shall be used to estimate NAA vehicle
     travel on off-network roadways within the urban transportation
     planning area, and on roadways outside the urban
     transportation planning area;

-    Reasonable methods in accordance with good practice must be
     used to estimate traffic speeds and delays in a manner that is
     sensitive to the estimated volume of travel on each roadway
     segment represented in network model, and

-    Ambient temperatures shall be consistent with those used to
     establish the emissions budget in the applicable
     implementation plan.  Factors other than temperatures, for
     example the fraction of travel in a hot stabilized engine
     mode, may be modified after interagency consultation if the
     newer estimates incorporate additional or more geographically
     specific information or represent a logically estimated trend
     in such factors beyond the period considered in the applicable
     implementation plan.

For areas that are not subject to the use of network models,
procedures that extrapolate historical VMT or may project future
VMT by considering growth in population and historical growth
trends for VMT per person can be used.  These procedures must also
consider future economic activity, transit alternatives, and
transportation system policies.

In terms of the CO hot-spot requirements, the analysis must be
based on the applicable air quality models, data bases and other
requirements specified in 40 CAR Part 51, Appendix W, "Guidelines
on Air Quality Models (Revised)" (1988), Supplement A (1987) and
Supplement B (1993), EPA publication No. 450/2-78-027R. 
Assumptions used in hot-spot analysis must be consistent with the
assumptions used in the regional emission analysis for those inputs
that are required for both analyses.  Requirements for PM10, hot
spot analyses have not yet been specified.  For construction-
related activities that cause temporary or self-correcting
increases in emissions, CO and PM10 hot-spot analyses are not
required.

The data requirements to support the conformity process is
extensive.  The data for the transportation plan and TIP includes;

-    Estimates of current and future land use patterns, population,
     demographics, and employment.

                                 73





-    Estimates of background levels of pollutants.

-    Transit fares, service levels, and ridership.

-    Regionally significant highway and transit facilities,
     services and activities;

-    On-going TDM or TSM activities;
     
-    Regionally significant projects which are currently under
     construction;

-    TCMs and regionally significant facilities, services, and
     activities which will be operational or in effect in the
     horizon years;

-    Fully-adopted and/or funded non-Federal TCMS;

-    Incremental effects of any non-Federal TCMs known to the MPO;
     and

-    Regionally significant non-FHWA/FTA highway and transit
     projects that will be implemented and completed by the horizon
     year.

The data required to support the transportation network modeling
include:

-    Transportation analysis zones
     
-    Highway and transit networks

-    Ground counts for a recent base year

-    Empirical observations of free flow speeds
     
-    Zone to zone modal split

-    Peak and offpeak travel times and travel demand

-    Travel cost information including auto operating costs,
     parking costs, transit fares, and tolls

-    Origin-destination and trip length information

-    Vehicle occupancy

Other data required to support the emissions analysis are:

-    HPMS estimates of VMT, and reasonable estimates of VMT where
     HPMS estimates are not available.
-    Ambient temperature assumptions as used for the emissions
     budget in the SIP.

                                 74





                   APPENDIX C - SUMMARY TABLES OF
                    CURRENT PLANNING REQUIREMENTS

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                                 91




              APPENDIX D - GIS & IVHS AS MODELING TOOLS






The planning requirements presented in this report demand specific
modeling needs as well as specific data collection activities that
are not currently available.  One way to improve the existing
models and their associated data collection activities is the
application of advanced technologies such as GIS and IVHS.  GIS can
provide detailed geographic specificity in the models, and IVHS can
provide real-time data collection and analysis.

GIS is already being used for a variety of planning activities in
State DOTS, transit agencies and MPOS".56  In terms of
transportation planning models, GIS could be used in the following
ways 57.58

-    To better estimate the share of jobs and households within
     various access distances of transit.
    
-    To better represent traffic analysis zones focused on transit
     nodes or major bus corridors, rather than on roadways;

-    To collect inventory data on urban and transportation
     infrastructure, such as transit stop location, sidewalk
     location, bicycle facilities, etc.:

-    To facilitate the identification and analysis of congestion;

-    To monitor land development and growth patterns, and their
     effect on transportation;

-    To provide the framework for the management systems discussed
     in Section 2.2.3 and

-    To provide consistency in the method and storage for
     metropolitan and statewide data collection efforts.

Fleet, et al discuss the implications for GIS-T as follows59.

-    This is a time of changing views on types of data needed and
     the methods and technology available to collect it;

-    The institutional structure of the planning/programming/
     implementation process is changing and many new players
     (implementing agencies) now have more active roles in the
     planning and decision making process;

____________________________
56   Carol L. Schweiger, Current Use of Geographic Information
Systems in Transit Planning, prepared for UTMT Office of Grants
Management, Final Report, August 1991, DOT-T-92-02.

57   Michael Replogle, "Improving Transportation Modeling for Air
Quality and Long-Range Planning," op. cit., P. 18.
58   Christopher Fleet, Charles Goodman and Ron Giguere, "Travel
Data Needs to Respond Effectively to Congestion Management and Air
Quality Planning," op. cit., pp. 4-5.

59   lbid, p. 11.

                                 93


-    There is a need to develop more of a "following" among the
     MPOs to implement GIS-1 and

-    This is a time when the technology of GIS that may offer
     significant help as a planning tool is itself changing so
     dramatically and rapidly.

-    There is potential for IVHS technologies to greatly improve
     the data collection and analysis, particularly through
     advanced traffic management systems (ATMS), and commercial
     vehicle operations (CVO) systems.  The following primary
     characteristics of ATMS60 relate specifically to the planning
     and data collection requirements discussed in this report;

-    Collection of real-time traffic data;

-    Reaction to changes in traffic flow with timely traffic
     strategies - predicting when and where congestion will occur
     based on real-time information, providing routing information
     to motorists, and making appropriate adjustments to control
     devices; and

-    Area-wide surveillance and detection systems.

-    In order to implement ATMS, real-time traffic monitoring and
     data management capabilities must be developed, including
     advanced detection technologies such as image processing
     systems, automated vehicle location and identification
     techniques, and the use of vehicles themselves as traffic
     probes."61 Currently, there are only a few examples of ATMS
     that include real-time traffic monitoring.

CVO systems will also provide real-time data collection through the
use of technologies such as automated vehicle identification,
automated vehicle classification, automated vehicle location and
weigh-in-motion systems.  Unfortunately, as with ATMS, there are
not many actual implementations of CVO technologies currently.

Even though many of the applicable IVHS technologies have not been
fully deployed, they still provide promise with respect to future
data collection techniques to fulfill the requirements discussed in
this report.


_____________________________
60   IVHS America, Strategic Plan for Intelligent Vehicle-Highway
Systems in the United States, May 20, 1992, Report No. IVHS-AMER-
92-3, p. 111-9.

61   lbid, pp.  III-9 through 111-10.

                                 94




                   APPENDIX E - LIST OF REFERENCES





LIST OF REFERENCES

1    1992 Transportation & Air Quality Planning Guidelines, July
     1992, EPA 420/R-92-001.

2.   AASHTO Guidelines for Traffic Data Program, 1992, ISBN 1-
     56051-054-4.

3.   "Air Quality: Transportation Plans, Programs, and Projects,
     Federal or State Implementation Plan Conformity; Rule," 58 FR
     62199-62253 (November 24, 1993).

4.   Citizens for a Better Environment and Jean Siri v. George
     Deukmejian, et al., and Sierra Club v. Metropolitan
     Transportation Commission, "Declaration of Dr. Peter R.
     Stopher in Support of Sierra Club's Objections to MTC's
     Proposed Conformity Assessment."

5.   Citizens for a Better Environment, et al v. George Deukmejian,
     et al., and Sierra Club v. Metropolitan Transportation
     Commission, "Memorandum of Points and Authorities in Support
     of Metropolitan Transportation Commission's Revised Conformity
     Assessment Procedures (1990 Clean Air Act Amendments)."

6.   Clean Air Act Amendments, Public Law 101-549, November 15,
     1990.

7.   Dial, Robert B., Frederick W. Ducca, and Bruce D. Spear,
     "Intermodal System Transportation Evaluation Program (ISTEP)
     Travel Model Improvements Study Design," Rough Partial Draft,
     December 1, 1992.

8.   Elsinger, Douglas S., Elizabeth A. Deakin, Lenna A. Mahoney,
     Ralph E. Morris, and Robert G. Ireson, Transportation Control
     Measures: State Implementation Plan Guidance, prepared for EPA
     and Pacific Environmental Services, Inc., Revised Final
     Report, SYSAPP-90/084, September 1990.

9.   Christopher Fleet, Charles Goodman and Ron Giguere, "Travel
     Data Needs to Respond Effectively to Congestion Management and
     Air Quality Planning," FHWA, presented at the 1993 Geographic
     Information Systems for Transportation Symposium, Albuquerque,
     NM, March 29-31, 1993.

10.  Guidelines for Travel Demand Analyses of Program Measures to
     Promote Carpools, Vanpools, and Public Transportation,
     Cambridge Systematics, Inc., prepared for the Federal Energy
     Administration, November 1976, Report No. FEA/B-77/33 1, NTIS
     No. PB-271 100.

11.  Harvey, Greig and Elizabeth Deakin, "Toward Improved Regional
     Transportation Modeling Practice," (Revised), December 1991.

12.  Hawthorn, Gary, "Transportation Provisions in the Clean Air
     Act Amendments of 1990," ITE Journal, April 1991.

13.  Highway Performance Monitoring System Field Manual, Office of
     Highway Information Management, December 1987 updated through
     April 20, 1990, FHWA Order M5600.  IA, OMB No. 2125-0028.

                                 95





14.  Highway Planning Program Manual, Volume 8 - Urban
     Transportation Planning, Bureau of Public Roads and FHWA,
     originally written and updated between September 1965 and
     August 1973.

15.  "The Intermodal Surface Transportation Efficiency Act of 1991:
     A Summary," Highway Users Federation and the Automotive Safety
     Foundation, pamphlet.

16.  "Intermodal Surface Transportation Efficiency Act of 1991,
     Implementation Guidance, Notice," 57 FR 14880-14953 (April 23,
     1992).

17.  Intermodal Surface Transportation Efficiency Act of 1991,
     Public Law 102-240, December 18, 1991.

18.  Loudon, William R. and Deborah A. Dagang, "Predicting the
     Impact of Transportation Control Measures on Travel Behavior
     and Pollutant Emissions," JHK & Associates, prepared for the
     1992 Transportation Research Board Annual Meeting, January
     1992.

19.  "Management and Monitoring Systems; Interim Final Rule," 58 FR
     63442-63485 (December 1, 1993).

20.  Manual of Regional Transportation Modeling Practice for Air
     Quality Analysis, NARC, July, 1993.

21.  Outwater, Maren L. and William R. Loudon, "Travel Forecasting
     Guidelines for the Federal and California Clean Air Act," JHK
     & Associates, prepared for the Transportation Research Board
     1994 Annual Meeting, January 1994.

22.  "Planning Assistance and Standards: Urban Transportation
     Planning; Final Rule," 40 FR 4297642984 (September 17, 1975).

23.  "Procedures for Emission Inventory Preparation, Volume IV:
     Mobile Sources," U.S. EPA, EPA450/4-81-026d (Revised), 1992.

36.  Methodologies for Estimating Emission and Travel Activity
     Effects of TCMS, Systems Applications International, prepared
     for EPA Offices of Air Quality Planning and Standards, and
     Mobile Sources, Draft Final Report, July 27, 1992, SYSAPP-
     92/096.

24.  Replogle, Michael, "Improving Transportation Modeling for Air
     Quality and Long-Range Planning," presentation to the TRB 1993
     Annual Meeting, January 1993.

25.  Schweiger, Carol L., Current Use of Geographic Information
     Systems in Transit Planning, prepared for UMTA Office of
     Grants Management, Final Report, August 1991, DOT-T-92-02.

26.  "Section 187 VMT Forecasting and Tracking Guidance," U.S. EPA,
     January 1992.

                                 96



27.  "State Implementation Plans;  General Preamble for the
     Implementation of Title I of the CAAA of 1990, Proposed Rule,"
     57 FR 13498-1313570 (April 16, 1992).

28.  "Statewide Planning; Metropolitan Planning; Rule," 58 FR
     58040-58079 (October 28, 1993).

34.  Stopher, Peter R. and Arnim H. Meyburg, Urban Transportation
     Modeling and Planning, Lexington, MA; Lexington Books, D.C.
     Heath and Co., 1975.

35.  Stopher, Peter R., "Deficiencies in Travel Forecasting
     Procedures Relative to the 1990 Clean Air Act Amendment
     Requirement," prepared for Conference Session on Implications
     of the 1990 Clean Air Act Amendments on Travel Demand
     Forecasting Techniques, 1992 TRB Annual Meeting, December
     1991.

29.  "A Summary: Transportation Programs and Provisions of the
     Clean Air Act Amendments of 1990," an FHWA pamphlet.

30.  Traffic Monitoring Guide, Office of Highway Information
     Management, October 1992, FHWA-PL92-017.

31.  "Transportation Consultant Services: Traffic Congestion and
     Capacity Increases," Applied Management and Planning Group,
     prepared for Sierra Club Legal Defense Fund, Inc. and Citizens
     for a Better Environment, August 1990.

32.  Transportation Control Measure Information Documents,
     Cambridge Systematics, Inc., prepared for the EPA, March 1992,
     Report No. EPA 400-R-92-006.

33.  "Travel Model Improvement Program," brochure from the Texas
     Transportation Institute, 1994.

37.  Weiner, Edward, Urban Transportation Planning in the United
     States: An Historical Overview, Office of Economics, Office of
     the Assistant Secretary for Policy and International Affairs,
     Office of the Secretary of Transportation, Revised Edition,
     November 1992, DOT-T-93-02.

                                 97



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