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The Transportation Plan for the Boston Region - Volume 2 - Nov 15, 1993

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                                                          VOLUME TWO
                                                     Resource Papers

                                                       Plan for the 
                                                       Boston Region

                                                   November 15, 1993

                               Central Transportation Planning Staff
                            Directed by the Boston Metropolitan Plan
                                Organization (MPO), which comprises:

                              Executive Office of Transportation and
                                       Construction, Commonwealth of
                          Massachusetts Bay Transportation Authority
                                    Massachusetts Bay Transportation
                                            Authority Advisory Boars
                                    Massachusetts Highway Department
                                        Massachusetts Port Authority
                                  Metropolitan Area Planning Council

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        The Boston Metropolitan Planning Organization Region

The preparation of this document was supported by the Massachusetts
Highway Department and Federal Highway Administration through
Massachusetts Highway Department Agreement 93218, by the Federal
Transit Administration through Technical Study Grant MA-80-X002,
and by state and local matching funds.

                          TABLE OF CONTENTS

                     VOLUME TWO-RESOURCE PAPERS


A.   Commuting Patterns                                          A-1

B.   The Transportation And Land Use Models                      B-1

C.   History Of Mass Transit Planning In The Boston Region       C-1



     These papers were researched and developed as part of the 1993
Transportation Plan for the Boston region.  Although they were not
included in Volume One of the Plan, they contain useful supporting
information and provide insights on regional transportation
planning issues.

     The first paper, Commuting Patterns, is a time-series analysis
of regional work-related travel.  It continues the analysis started
with the Demographics of Commuting in Greater Boston, a report
prepared for the Boston Metropolitan Planning Organization by the
Central Transportation Planning Staff (CTPS) in 1989; an update of
this report will be available in the Fall of 1993.  Commuting
Patterns, prepared by Stephen Falbel of CTPS, incorporates
information from the 1990 U.S. Census Journey-to-Work survey.

     The second paper, The Transportation and Land Use Models, is a
concise description of the computer-based models that were used to
help analyze future travel conditions.  Prepared by Karl
Quackenbush of CTPS, the paper outlines key modeling issues,
describes the current effort to extend and improve the Boston
region's transportation and land use models, and identifies
improvements that will be made in coming months.

     The last paper, History of Mass Transit Planning in the Boston
Region, presents a review of the development of the region's mass
transportation system.  Beginning in 1894, the paper takes the
reader through the planning and implementation of public
transportation facilities.  Prepared by Stephen Falbel, the history
attempts to place the current planning effort, represented by the
Transportation Plan, in the context of historical planning efforts.


                        A. COMMUTING PATTERNS

     Commuting is at the core of many of the issues of
transportation, for it is the morning and afternoon peaks, the rush
hours every day, which determine what roads and transit systems are
most needed.  Transportation infrastructure must be designed to
serve the peak volume, not merely the average traffic volume spread
over an entire day.  Thus at the basis of any transportation plan
must lie an understanding of the patterns of commuting in the
metropolitan region.

     Journey-to-Work data from the US Census provide a wealth of
information on commuting patterns.  The long form of the Census,
sent to a random sample of the population, asks questions on the
location of the respondent's work place and the means of transport
used to get to work.  Data on commuting patterns are available from
the last three Censuses: 1970,1980 and 1990.


     Each weekday, 607,000 work trips are made to Boston and
Cambridge, representing 35.3 percent of all work trips made within
the 101 cities and towns of the Boston MPO region.  Of these,
341,600 (57.7 percent) are made by automobile, 187,200 (31.6
percent) are made by transit, 53,900 (9.1 percent) are made by
walking, and 9,100 (1.5 percent) are made by other modes.

     As would be expected, the number of trips to and from the
urban core declines with distance, but large numbers of trips are
made even from very long distances.  Figure A-11 shows the number
of commuters to the urban core, defined here as the cities of
Boston and Cambridge.  Over 240,000 urban core workers live in the
urban core.  Communities immediately surrounding Boston and
Cambridge send in large numbers of workers-190,320 from the 28
other communities within Route 128.  Between Route 128 and I-495,
the numbers are smaller but the slow rate at which they diminish
demonstrates the strength and extent of the influence of the urban
core.  Communities from beyond I-495 such as Nashua, Manchester and
Salem, New Hampshire, Worcester, Providence, New Bedford, and
Barnstable each have more than 500 residents that commute to

1Figure A-1, and subsequent figures in this chapter, display trips
made from 388 cities and towns in five of the six New England
states.  This 388-community region extends to roughly a sixty-five
mile radius around downtown Boston and encompasses several
metropolitan areas.  Worcester, Providence, Fall River, New
Bedford, Brockton, Lowell, Lawrence, Haverhill, Fitchburg, and
Manchester, Nashua, Concord and Portsmouth New Hampshire, among
others.  This area is home to approximately 7 million people.


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the urban core.  Over 100 people commute from Falmouth, Warwick,
Rhode Island, Concord and Portsmouth, New Hampshire and York,
Maine-these commutes being nearly one and a half hours each way. 
Smaller numbers of people, in the range of 40 to 80, commute from
as far away as Kennebunk, Maine, Springfield, Massachusetts and
Newport, Rhode Island.

     Figure A-1 also shows that the number of commuters to the
urban core is closely correlated with transportation access to the
core.  All of the communities with the highest number of Boston and
Cambridge workers are located on a major expressway.


     Looking at the historical trends in the commuting pattern to
the urban core, one finds a tendency toward lengthening commuting
trips.  Figure A-2 shows the percentage change in the number of
commuters to the urban core for those cities and towns which sent
at least fifty commuters to Boston and Cambridge in 1980.  The
majority of the close-in communities are in the "stable" category
(i.e. less than 10% change up or down) while some experienced a
significant decline.  For communities with rapid growth in the
number of commuters to the urban core, one has to go out the I-495
ring and beyond.  Several of these more distant communities
experienced a doubling or even a three and four-fold increase in
commuters to Boston and Cambridge.  The area with the most
consistent, fast growth is the southwestern stretch of I-495,
between Ashland and Taunton.  This segment of expressway was
completed only in the late 1970s and 1980s.  An increase in the
number of commuting trips from distant locations combined with a
decrease in trips from close-in locations yields an increase in the
average trip length.  Census data on work trip travel time support
this conclusion, showing that the average work trip in eastern
Massachusetts increased from 22.8 minutes in 1980 to 24.1 minutes
in 1990.

     Figure A-3 displays the percent change in commuters from 1970
to 1990 for communities with at least fifty commuters to the urban
core in 1970.  Unfortunately, 1970 data were not available for New
Hampshire and Maine, so it is impossible to measure the growth in
those states.  Cities and towns in Massachusetts, though, exhibit a
striking pattern of growth, most notably along the southwestern
stretch of I-495 all the way from Northborough to Taunton,
influenced, undoubtedly, by the construction of that expressway
during this period.  In addition, rapid increases appear in
Plymouth and on the Cape.  A few of these communities saw nearly a
five-fold increase in the number of people traveling to the urban
core for work between 1970 and 1990.  The northeastern portion of
Massachusetts also displayed growth, although not as fast as the
aforementioned areas.  Closer-in communities had smaller percentage
increases in urban core commuters, but since these cities and towns
sent large numbers of people in 1970, these small percent increases
translate into large absolute increases.


     While the change in number of commuters provides some
perspective on shifts in commuting patterns, from a transportation
standpoint, it is important to study trends in travel patterns for
particular modes of travel.  Figure A-4 contains two maps of the
central portion of the study area showing the changes in mode
shares between 1980 and 1990 for single occupant drivers and
transit riders to the urban core.2

     The maps portray an overall shift toward single occupant
vehicles (SOVS) for the journey to work to the urban core between
1980 and 1990.  The upper map shows most of the cities and towns in
the region experiencing an increase in the percent share for SOVs
between 5 and 25 points.  A few towns to the west, from Westborough
to Westford, had somewhat larger shifts toward SOVS, up to 50
points.  Although there are a few scattered communities which saw
the percentage of commuters driving alone drop during the 1980s,
the only portion of the region where this happened with any
consistency was in the southwest, around Ashland, Bellingham and

     Looking at the second map, this southwestern area can be seen
as clearly different from the rest of the region.  While most areas
had a stable or moderately declining transit mode share, cities and
towns stretching from Canton and Stoughton, up to Natick, down to
Mansfield, and out to Uxbridge saw the percentage of their
commuters to the urban core using transit rise by 5 to 25 points. 
Most of this increase occurred on commuter rail, which can be
explained by improvements to the Franklin and Attleboro lines made
during the 1980s, including new equipment, the improved Southwest
Corridor, and the opening of a large park'n'ride facility at Forge
Park/I-495 station.

     In other parts of the region, most of the decrease in transit
mode share is due to declining bus ridership.  This decline may be
somewhat overstated because bus ridership may have been
artificially high in 1980 as a result of the 1979 oil crisis.  One
final point about this map is that declining or stable transit mode
share does not imply declining or stable ridership.  With the
increase in urban core employment and its corollary increase in the
number of commuters to the urban core, a stable, or even slightly
declining mode share could represent an increase in the number of
riders, albeit a small increase relative to the increases in other
modes. (For example, while the transit mode share declined by 0.3
percentage points between 1980 and 1990, MBTA ridership increased
by nearly 20 percent between 1983 and 1993.)

2Data are unavailable for the rest of the study area.


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     The percent share of commuters who used to get to the urban
core in 1990 is displayed in Figure A-5.  This map has several
interesting features.  The cities and towns immediately surrounding
the core have high transit shares, as one would expect, given the
high level of transit service provided by the local and express
buses and subway lines.3  Some of the most distant communities also
have high transit shares, reflecting strong patronage of private
bus companies.  For many people, such trips are too long to drive
every day.  Buses offer a more relaxing and often cheaper way to
get to the downtown area.

     The effect of commuter rail service is clearly shown,
particularly on the North Shore up to Rockport and to the southwest
along the Franklin line and especially the Attleboro/Providence
line.  In these two corridors (northeast and southwest), commuter
rail offers travel times competitive to the automobile, presumably
because I-95 from Canton through Boston and up to Peabody was never
built.  On the Haverhill and Lowell lines, the terminal city has a
high transit share while many of the intermediate communities have
lower shares.  On the Fitchburg line, all of the communities past
Ayer have low shares, reflecting the relatively low ridership on
that segment of the system.

     A map of mode share for single occupant automobiles, shown in
Figure A-6, is almost an inverse of Figure A-5.  These trips are
least common in the downtown area, in the southwest corridor down
to Providence, and in some of the communities at the edge of the
study area.  In addition, the area around Fall River and New
Bedford exhibits a very low mode share for SOV because of a large
amount of carpooling (in the range of 30%) as well as high bus

3The cities and towns of the core area do not fall into the highest
category of transit share because significant numbers of residents
walk to work:  32% of Cambridge residents and 18% of Boston
residents walk to urban core jobs.


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     Up to this point we have looked only at commuting to the urban
core of Boston and Cambridge.  These two cities, although the
largest employers in the UTO region, provide only 35% of the total
employment.  Much of the rest of the employment is located in
suburban job centers along Route 128 and in other satellite cities.

     Suburban communities along Route 128 draw employees from a
wide area in much the same manner as the core, but in lower total
volumes.  These characteristics point out the basic problem in
providing attractive transit services to and from these areas:
although the geographical extent of the need for service is almost
as large as for the core, the lower volumes are not sufficient to
support frequent (and thus convenient) service.  Three specific
examples are Waltham, Burlington, and Braintree, which are large
employment centers along Route 128.

     Waltham, which is the largest employment center on Route 128,
has less than one-tenth the employment of the urban core (57,000
versus 607,000).  However, as shown in Figure A-7, Waltham
employees travel from distances nearly as long as those to Boston
and Cambridge, with commuters coming from as far away as Concord,
New Hampshire, Springfield and Barnstable, Massachusetts, and
Warwick, Rhode Island.  Cities and towns sending more than 100
commuters to Waltham are not quite as spread out, extending to
Haverhill, Nashua, Worcester, Attleboro and New Bedford.  One
explanation why Waltham draws employees from such great distances
may be that much of the employment in Waltham is in high-tech
industries.  Because these jobs call for specialized skills, the
high-tech firms must draw from a very large labor pool, including
people in other New England states.

     Waltham has a significant amount of transit service: five
local MBTA bus routes, one express MBTA bus route, and commuter
rail.  However, these services are oriented around downtown Waltham
and toward urban core commuting, and do not serve Route 128
employment centers.  The design of these services reflects existing
travel volumes: 5,440 Waltham residents commute each day to the
urban core (1,190 on transit-a 22% share), but no more than 4,600
(from Boston) travel to Waltham from any single community.4  Of all
57,000 commuters to Waltham, only 1,200 (2%) used transit.

     Burlington, shown in Figure A-8, is a smaller but faster
growing job center on Route 128.  It employed 32,000 people in
1990, just over half the employment of Waltham, but grew by 9,000
new jobs in the 1980s, almost a 50% increase in employment. 
Despite its smaller size, Burlington draws commuters from

4 Over 14,000 Waltham residents work in Waltham.  After Boston, the
next largest source community for Waltham workers is Newton at
2,500.  Of Boston's commuters to Waltham 414 used transit (9%).


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distances as long as Waltham and the urban core.  Like Waltham, the
long distances may be partly explained by the high-tech nature of
employment in Burlington.  Another explanation is that the high
housing prices of the mid and late 1980s forced the people filling
the newly created jobs in Burlington to live at the edges of the
urban area, far from their work places.  A particular feature of
Burlington is that it imports a huge percentage of its work force: 
88% of the work force lives out of town, compared to 75% for
Waltham and 64% for the urban core.  In addition, no other
community houses a large concentration of Burlington's workers-
medium-size concentrations of 500 to 2,000 are spread over several
cities and towns stretching from Boston to Nashua.  Burlington is
served by three MBTA bus routes-two are oriented toward urban core
commuting, and the other is oriented toward work trips from Boston
to Burlington.  (The town also operates a mini-bus service, but
this service is not designed to serve work trips and begins
operation after the end of the AM peak.)  Only 1.65 percent of the
Burlington work force commutes on transit.

     Finally, Braintree, located at the southeastern end of the
circumferential highway at the intersection with Route 3 and the
Southeast Expressway, exhibits somewhat different characteristics,
as shown in Figure A-9.  It has roughly the same employment at
Burlington, with nearly 30,000 jobs, but the extent of its commuter
source area is noticeably smaller.  It imports a large percentage
of its work force at 84%, but many of the imported workers are
concentrated in a few nearby cities: Boston, Quincy and Weymouth. 
Braintree's employment is less high-tech and more of the generic
commercial and office variety, and thus can draw form a smaller
labor pool.  Braintree has transit service, with the Red Line and
several bus routes, and will have even more when the Old Colony
line is restored.  However, these services do not reach the parts
of Braintree where most of the employment is located.  As a result,
in spite of the current service, less than 4% of the work force
uses transit to get to work.


     The Census Journey-to-Work data provide much information on
commuting patterns in the region.  People are commuting very long
distances, up to one and a half hours each way, to reach their jobs
in the urban core.  Over the past two decades, these trips have
been lengthening, and more often than not, people have chosen to
drive alone rather than carpool or take some form of public
transport.  There are several explanations for these trends. 
Housing prices rose steeply in the 1980s, forcing people to go
outside of I-495 to find an affordable suburban-style home.  At the
same time, the costs associated with private transportation were
falling relative to other goods: fuel prices dropped sharply in the
mid '80s, cars have become more comfortable and reliable, and
expressway construction in the '60s and 70s reduced travel times
from distant locations.  Of course, highway congestion has
increased travel times, mitigating the effect of the improvement in

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     Transit has retained a high share of the market in places
where it offers service competitive to the automobile.  In the
urban core, the cost of parking often outweighs a car's travel time
advantage.  For very long distance trips, an express bus is as fast
as a car and can be cheaper, especially considering parking costs. 
Along certain commuter rail lines to the northeast and southwest,
automobile access times are inferior, making transit attractive.

     For commuting to suburban work places, mode shares of higher
than 80% for single occupant vehicles, and higher than 90% for SOV
and carpool combined, are the rule.  Transit garners 2 to 4% on an
average and even less for Burlington.  Using transit in the suburbs
is undoubtedly less convenient than using a car, and with the added
bonus of plentiful free parking, there is hardly any incentive not
to drive.  Commuting to suburban jobs is therefore automobile
commuting, rather than the multimodal commuting characteristic of
the urban core.

     Congestion is usually associated with commuting to the urban
core, and for good reason:  expressways leading to the core are
filled to capacity every day, as are many of the transit services
to the downtown area.  However, congestion is an increasing problem
in suburban locations.  With the long commuting distances, many
miles are being travelled.  Highway space is limited and there are
few travel options.  Thus, even with employment levels well below
those of the urban core, congestion can be just as severe in the

     It may not be possible to build our way out of the problem in
the suburbs because new expressway construction may encourage more
suburban development leading to more travel and thus more
congestion.  Density in the suburbs may never reach the level
necessary to support a conventional transit system.  The solution
may therefore reside in a combination of better land use planning-
providing more housing near to employment centers and locating work
places in areas accessible by transit-and participation by
employers in transportation management associations to promote
ridesharing and offering shuttle services to transit stations.

     For the urban core, it is crucial to keep the transit system
as a viable option-without it, the highways of the region would be
clogged.  The future lies with a balanced multimodal approach.




     This resource paper discusses the land use and transportation
models that were used to generate travel forecasts and statistics
for the alternative scenarios of the draft Transportation Plan for
the Boston region.  The discussion is intended to be non-technical
and to provide the reader with a general understanding of the
nature of regional modeling and its role in the regional
Transportation Plan.

     The paper begins with an overview of the nature and role of
the Boston MPO's regional model set.  Then there is a discussion of
how the model set was recently updated for use in the draft
Transportation Plan, followed by a brief description of the steps
in the model set.  The paper closes with some information about how
the model set will be further improved in the future.


     A regional land use/transportation model set is composed of
several models that together simulate intra-regional passenger
transportation supply and demand for the current and future years. 
Supply enters the model set in the form of a computerized
representation of the region's highway and transit systems.  All
express highways and major arterials, most minor arterials and many
local roadways are included.  All transit lines, both public and
private, are included.  Demand enters the model in the form of
weekday trips that are generated from population, employment and
land use.

     A regional model set is used to forecast changes in regional
travel patterns that would result from certain actions. 
Historically, those actions have focused on major new or widened
roadways and new or extended transit lines.  Also, regional models
have been used to estimate the system wide travel effects of
changes in such things as transit fares, parking price or supply
and fuel prices.  Recently, regional models have come to be used in
forecasting the impacts of transportation system changes on air

     Travel forecasting models used at a regional level are
appropriate for developing regional transportation plans, but are
not necessarily the best tool in all planning situations.  Precise
and accurate forecasts of roadway traffic volumes and transit line
volumes are often obtained by using these same models, but at a
corridor or subarea level, where supply and demand variables can be
represented with more detail and where relationships in the models
can be calibrated more precisely.  Even more fine-grained
forecasts, such as those of intersection levels-of-service must be
obtained from operations-level traffic forecasting models.


     The Intermodal Surface Transportation Efficiency Act of 1991
and the Clean Air Act Amendments of 1990 have placed new demands on
travel forecasting models and on those who develop and use them. 
These models are being relied on for guidance in how transportation
investments inter-relate with land use patterns, air quality and
livable communities.  Neither this region's nor any other region's
models can provide all of the guidance being sought, but the models
used in the transportation plan were recently updated and are more
responsive to some of these issues than they were before.


     Travel models need to be updated periodically.  At a minimum,
they must be recalibrated with new data it becomes available.  In
addition, their structures must be updated to maintain currency
with evolving research and the state-of-the practice.  The Boston
Metropolitan Planning Organization regional model set, which is
maintained by the Central Transportation Planning Staff (CTPS), is
in the process of being updated for these reasons and in order to
make it more responsive to the recent federal mandates referred to
above.  It will be another year before the update process is
complete, but that process yielded an "interim" model for use in
the Transportation Plan.

Steps in Model Update Process
     The process of developing a new interim model set involved
several steps, the first of which was to acquire a new data base. 
Early on, some new computer software, notably a land use allocation
model, was also acquired.  After these acquisitions, many months
were devoted to modifying some elements of the model process and
completely revamping others.  All elements of the process were then
connected to one another and implemented on a mainframe computer.

     Model calibration was then undertaken.  Calibration refers to
repeatedly running the model set and adjusting certain of its
components until it replicates current regional travel patterns at
an acceptable level of accuracy.  Once the model set was calibrated
to current conditions, it was used to forecast future conditions
associated with the various scenarios described in this
transportation plan.

New Data Used in Model Update
     Acquiring new data was crucial to the model update process. 
Several types of data, including the following, were obtained:

         Characteristics of region's travelers and of their trips
         Current and forecast regional population and employment
         Community land use and zoning information
         Traffic and transit counts


     Among the more important data sources was a travel diary, used
to collect information from 3,900 of the region's households. 
Descriptive data about households and their members was obtained,
as was detailed information about the trips they make each day. 
This information was expanded to represent all of the region's
residents and used to refine and reformulate certain portions of
the model set.  Socio-economic data from the 1990 U.S. Census
supplemented the survey data.

     CTPS developed a comprehensive file of current population and
employment from various sources, including the Metropolitan Area
Planning Council (MAPC), the 1990 U.S. Census, the Massachusetts
Department of Employment and Training and a commercial vendor. 
Forecasts of future-year population and employment were obtained
from the MAPC.  Community land use and zoning information was
collected from the MAPC and individual towns and used in the land
use allocation model.

     Current traffic and transit ridership counts were acquired
from the state transportation agencies and other sources and used
in model calibration.

New Interim Model Versus Old Models
     The new interim model differs from those previously used at
CTPS in several key respects.  First, it is a single comprehensive
regional model, used for highway, transit and high-occupancy
vehicle (HOV) forecasting.  In the past, three separate sets of
models were used for each of these travel modes.  The new model set
is based entirely on new data, as described above, and incorporates
many modified and brand-new steps.  Because of these features, the
new model is more accurate and sensitive to a wider array of policy
variables than were the old ones.  In short, it can do more things
and do them better than the old models.

     The integration of a land use allocation model with the
transportation models radically changed the nature of the regional
model process.  In the past, population and employment forecasts
input to the transportation models were always pre-determined and
they remained unchanged in the modeling process.  Now the land use
allocation model allows us not only to forecast the impact of
population and employment on transportation, but also to test how
transportation might, in turn, shift the patterns of those
variables across the region.

     Regional employment forecasts used in the new model set are
different from those used in the old models.  The differences in
employment projections between the old and new models translate
into differences in the future trips that are generated, in part,
from those projections.  The old forecasts implied a central Boston
employment growth of about 30 percent between 1987 and 2010.  The
new MAPC forecasts imply a central Boston employment growth of only
seven-to-eight percent between 1990 and 2020.  In consequence, the
forecast of central Boston-bound trips is now lower than before. 
In particular, since most transit trips are made to and from that
area, system wide transit ridership forecasts output from the new
model are lower than before.



     The transportation model used in the Transportation Plan is
similar to those used in most large North American cities.  It is
commonly referred to as the four step urban travel demand
forecasting process or simply as the four-step process.  There are
actually several more steps to the process; the four steps refer to
the major ones.  The four steps are:  trip generation, trip
distribution, mode split and trip assignment.  With the addition of
a land use allocation model, there are five major steps in the
model process.  Figure B-1 shows the relationships among these

     In the course of constructing a model set, the region was
subdivided into small geographic areas called traffic analysis
zones or simply zones.  These zones, many of which are similar in
size to Census tracts, serve as the basic geographic units for
which trips are forecast.  Also in the model development stage, the
region's transportation supply, in the form of roadways and transit
lines, was represented in computerized networks.  These networks
are used to derive travel times by travel mode from each zone to
every other one.  These times are then used in the trip
distribution and mode split steps.  The networks themselves are
used in the trip assignment step.  The zone system and the networks
are connected to one another to allow for interaction between
demand and supply.

Land Use Allocation Model
     The land use allocation model spatially allocates forecasts of
total regional population and employment among traffic analysis
zones.  Employment for a given forecast year is allocated to a
given zone on the basis of historical levels of employment and
population in that zone, total land area in the zone and the
accessibility of that zone from other zones where people live. 
Population is allocated to a given zone based on its historical
population, forecast employment level, amount of residential land,
vacant developable land and the accessibility of that zone to other
zones where people work.

     Use of an integrated land use/transportation model allows for
a linkage between the locations of activities and transportation
system accessibility.  Land use models used alone ignore the
effects of spatial activity allocation on the transportation
system.  Transportation models used alone ignore the effects of
transportation systems on the spatial allocation of activities.

Trip Generation
     The trip generation model takes the allocated population and
employment from the land use allocation model and translates that
to trips into and out of each zone.  It does so for several
different trip purposes (work, school, shopping, social, personal
business).  This is an extremely important step because it yields
the basic number of trips in the regional transportation system. 
Subsequent steps simply


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allocate those trips spatially, modally and temporally.  Completely
new trip generation equations were developed in the model update

Trip Distribution
     Trip distribution spatially allocates the trips generated in
the previous step.  Trip generation deals solely with how many
trips begin or end in a given zone, without reference to where the
other ends of those trips are located.  Distribution links trips
among zones:  it deals with where all trips begin and end.  Trips
that start in a given zone are forecast to end in another given
zone as a function of how far apart the two zones are from each
other and how many trips each zone generates in total.  The longer
the travel time between two zones, the fewer trips will flow
between them, all other things being equal.  On the other hand, the
more total trips a zone generates, relative to all zones, the
greater the "pull" it will have on a given origin zone; hence, the
more of that origin zone's trips it will attract to itself. 
Distribution results in a matrix of trips among zone's for each
trip purpose.  This model was modified somewhat in the update
process, but its basic structure remained unchanged from previous
model versions.

Mode Split
     In the mode split (or mode choice) step, the matrices of trips
by purpose output from distribution are allocated to competing
travel modes.  The model that does this considers the times and
costs associated with the competing modes and certain
characteristics (e.g., auto ownership, forecast with one of the
sub-models in the model process) of the travelers being modeled. 
Work trips are split among the transit, drive alone, 2-person
carpool and 3-or-more person carpool modes.  Nonwork trips are just
split between transit and automobile, irrespective of automobile
occupancy.  This model is critically important for the
Transportation Plan because it predicts shifts from the auto to the
transit mode that could be expected to occur as a result of
implementing various transit projects.  The model update process
resulted in a brand-new work trip mode choice model.

Trip Assignment
     The final step in the model process is trip assignment.  In
this step, the trips split by mode from the previous step are
assigned to the appropriate computerized networks in order to
predict which routes those trips will choose in the highway and
transit networks.  It is from this step that we produce statistics
such as regional vehicle-miles-traveled, vehicle-hours-traveled and
average operating speed.  From this procedure, we also produce
predicted traffic volumes along specific roadways and transit
ridership on specific lines.  Trip assignment procedures were
modified in the model update process.

     Also output from trip assignment are highway travel times
under congested conditions and transit travel times.  These are
combined and input back into the land use model in order to
forecast how transportation system accessibility, measured by
travel times, might lead to a reallocation of population and
employment.  These times are also input back into the trip
distribution and mode


choice steps as well, and for any given model scenario, those steps
and trip assignment are run through a second or even third time in
order to reach a rough equilibrium state among all steps of the
land use/transportation model set.

     After the travel models are run, regional air pollution
emissions can be calculated.  This is done by combining information
from Environmental Protection Agency (EPA)-approved emissions
models with the results from the trip assignment procedures.


     As stated previously in this paper, development of the travel
demand model for the Boston region is not complete.  The model used
for the Transportation Plan is termed "interim"; a final model will
be available in 1994.  It will differ from the interim model in
three broad respects.  First, CTPS will have completely redone
certain steps in the model that, for now, have simply been modified
or left alone.  The trip distribution model will, for instance,
probably be completely reformulated to make it responsive to travel
cost as well as to time.

     Second, CTPS will have collected and used additional data to
refine the model further.  This will, for example, include some
survey work to obtain information on unique trip generators such as
sports complexes and military installations.  Trips to and from
these kinds of facilities are not well represented in the standard
model process described above.  Getting better information about
them will enhance the accuracy of the forecasts.

     Finally, by next year, CTPS will have tied the individual
model steps together more tightly and calibrated the entire land
use/transportation model set more precisely.  At present, the land
use allocation model, being brand-new in the process, does not
yield results as satisfactory as will be required in the future. 
The trip assignments must be further refined in order to enhance
their accuracy at the level of individual roadways and transit


     The 1993 Transportation Plan analysis of future travel and air
quality conditions would not have been possible without the models
described in this paper.  The Boston Metropolitan Planning
Organization has made a commitment to continue to improve these
models, since they are among the tools necessary for planning and
management of the regional transportation system.  The next update
of the Transportation Plan, to be completed by January, 1995, will
rely on the final versions of the these regional travel and land
use models.


                        IN THE BOSTON REGION

     The public transportation system of the Greater Boston area
has a long and complex history.  What today is an integrated,
publicly owned and operated system, began as a number of private
ventures, hoping to produce profits by capitalizing on the ever
growing demand for mobility.

     Over the hundred years since the beginning of public
involvement in the construction of mass transit facilities,
planning for the public transportation system has proceeded in fits
and starts.  This chapter will examine the periodic planning
efforts which have brought the Boston area to its current mass
transit system made up of rapid transit, light rail and commuter
rail lines (see Figure C-1). A study of the private investments and
plans for streetcar lines and railroads would be very interesting,
but it is beyond the scope of the present chapter.1


     The first large scale planning effort for public
transportation facilities in the Boston area occurred with the
establishment of the Boston Transit Commission and the Boston
Elevated Railway Company in 1894.  Prior to that time, many miles
of streetcar track had been laid, but this construction had been
undertaken by private entrepreneurs, driven by market forces rather
than a comprehensive plan.  In the early 1890's, when the downtown
area was severely congested with,streetcar traffic, the City of
Boston decided that the time had come to invest in rapid transit
facilities.  The City chose both elevated lines, which had been in
use for several years in New York and Chicago, and subways, which
had not yet been tried anywhere in North America.  The
Massachusetts legislature passed an act in 1894 to "Incorporate the
Boston Elevated Railway Company and to Promote Rapid Transit in the
City of Boston and Vicinity.2  This act called for three elevated
and three subway lines to form the basis for a rapid transit
network.  Only two of these six projects were constructed in the
way contemplated when the 1894 act was passed, namely the Tremont
Street Subway from Shawmut Avenue to Scollay Square (now part of
the Green line)3 and the

1 The numerous bus and former streetcar lines will also not be
discussed, since they were not considered in detail in any of the
major planning studies.  Likewise, the planning of the commuter
rail system will not be discussed, since it was privately owned and
operated until the 1970s.
2 Stat.1894, Chapter 548.
3 Throughout this chapter, cross-references to the color scheme
familiar to today's riders will be given in parentheses.  The color
scheme was instituted by the newly-formed MBTA in 1965.


East Boston Tunnel from Scollay Square to Maverick Square in East
Boston (part of the Blue Line).  But the fact that the statute laid
out a large network with many branches makes it an important
landmark in systems planning and the history of urban transit.


     Several other acts of the legislature in the ensuing years
altered the proposals made in the 1894 act and authorized the
transit lines that were actually built.  Chapter 534 of the acts of
1902 laid out plans for the Washington Street Tunnel (Orange Line
from North Station to Chinatown).  Chapter 520 of the acts of 1906
described the Cambridge subway (Red Line from Harvard to Park
Street) Finally, Chapter 741 of the acts of 1911 prepared the way
for the Dorchester Tunnel from Park Street to Andrew (southern
portion of the Red Line), the Boylston Street Subway from Kenmore
to Tremont Street (Green Line) and a continuation of the East
Boston Tunnel from Court Street to Bowdoin Square (western section
of the Blue Line).


     The first major planning document to be produced after the
core of the transit system was in place was the Report on Improved
Transportation Facilities in the Boston Metropolitan District,
published by the Division of Metropolitan Planning4 in 1926.  This
report based its proposals upon 1) a study of population trends in
the Boston area, 2) an analysis of ridership trends on the many
steam railroad lines and on the streetcar and rapid transit system,
and 3) a survey of trouble spots in the existing system.  The
authors found that population was growing very quickly in the
suburban areas immediately surrounding Boston, especially those to
the west and south, such-as Newton, Needham and Dedham, but that
patronage of the steam railroads within five or six miles of the
city was declining steeply.  The railroads had lost their inner
suburb commuter patronage to the streetcar and rapid transit
facilities of the urban core in the early part of the century, and
as the 1920's wore on, even more people were leaving the railroads
to drive their own private automobiles.  The automobile had not yet
cut significantly into the patronage of the Boston Elevated (called
the "El"), which then served an average of one million passengers
per day, but it was predicted that increasing numbers of people
would desert the El because of congestion and inconvenience if
improvements were not made to the transit facilities.
Improvements were deemed to be especially necessary at the Park
Street and Scollay Square stations which, because of the large
number of trolley lines (eleven separate routes) which originated
and terminated there, were subject to a severe congestion problem
compounded by confusion and delays in loading and

4 Part of the Metropolitan District Commission


Click HERE for graphic.

unloading passengers.  The Planning Division recommended several
the system to alleviate this problem and also to provide more
comprehensive service to the territory within five miles of the
State House, which was seen as the proper domain of rapid transit.

     Two projects received top priority:  a through route between
Maverick Square and Warren Street or Lake Street, Brighton which
was essentially a connection between the East Boston Tunnel (Blue
line) and the Tremont Street and Boylston Street Subways (Green
Line) emerging along Commonwealth Avenue; and a route from Lechmere
to Huntington Avenue through the Tremont Street Subway, along the
Albany and New Haven Railroad tracks and then along Huntington
Avenue to a terminal at Tremont Street in Roxbury (see Figure C-2). 
These through routes operating in the Tremont Street subway would
replace the eleven trolley routes and thereby greatly improve the
congestion problems.  Neither of these routes was ultimately
instituted, although service along Huntington Avenue was eventually
put into place with the opening of the Huntington Avenue Subway in
1941.  As it turned out, several other proposals in the 1926
report, judged to be of lower priority, were actually carried out. 
These include:

         Extension of East Boston route to Lynn via the Boston,
          Revere Beach and Lynn Narrow Gauge Railroad completed as
          far as Revere in 1952
         Conversion of the Western Division of the Boston and
          Maine Railroad as far as Reading to a new rapid transit
          line-completed as far as Oak Grove in 1975-77
         Use of the Old Colony Railroad tracks for a transit
          extension to Braintree-completed in 1980
         New transit line parallel to Providence Division of the
          New Haven Railroad to Forest Hills-completed in 1987
         Extension of Huntington Avenue route through Brookline
          Village connecting to the Highland Branch of the Boston
          and Albany Railroad-use of the Highland Branch for the D
          Line through Kenmore instead completed in 1959 (Note: 
          the connection from Brigham Circle to Brookline Village
          is still being considered).

     There were also several other proposals which were
subsequently dropped from consideration as well as two which have
reappeared on the agenda:

         Extension from Lechmere to Woburn via Southern Division
          of the Boston and Maine Railroad-extension as fall as
          Medford Hillside is currently being considered.
         Suggested study of a circumferential transit route as
          proposed by the City of Boston in 1923 (no particular
          alignment mentioned).

     The second major function of the 1926 report was to suggest
ways to solve the problem of the chronic deficits of the transit
agencies.  Since 1918, the Boston


Elevated had been under public control, but its financial problems
had not ended.  The report recommended the establishment of a
corporation, owned by private stockholders, to be called the
Metropolitan Transit System, which would assume the assets and
liabilities of the El for a period of at least forty years.  The
directors of this corporation would be appointed by the governor
and thus, although it would not be a state agency, control would be
in the public domain.  It was further recommended that the district
for this new agency be expanded to twenty-nine cities and towns
from the fourteen communities which had been bearing the deficits
of the El under the Public Control Act of 1918.  These suggestions
were not followed until 1947 when the Metropolitan Transit
Authority was created in response to the reports of the Coolidge


     In 1943, the legislature decided it was again time for an
evaluation of the future shape of the rapid transit system and
created the Metropolitan Transit Recess Commission headed by
Senator Arthur W. Coolidge "for the purpose of making an
investigation and study of the subject of rapid transit in the
boston metropolitan area."5  The Coolidge Commission, as it cam to
be known, produced a report in April of 1945 and a second revised
edition in 1947.  As did the 1026 report, the Coolidge Commission
report had two primary functions:  to propose a layout for a
transit system to fulfill the future needs of the Boston
metropolitan area, and to recommend a reorganization of the transit
agency to solve the perennial problem of the deficits of the Boston

     The Coolidge Commission considered population trends between
1900 and 1940 and concluded that the urban core areas were on the
decline and that suburbs between five and ten miles from the State
House were growing quickly.  The Commission argued that the current
demise of the public transportation system and the concurrent
increase in automobile traffic congestion was a result of this
population movement, since the existing rapid transit system only
extended as far as five or six miles from the center of Boston. 
The report declares: "The obvious solution [to these problems] is
the extension of rapid transit lines out to the areas where the
population is growing, sufficiently extended to aid the development
of the areas and to facilitate the movement of the population to
and from the center of the City of Boston."6

     Specific proposals were based upon studies of the existing
system and possible transit extensions using railroad rights-of-
way.  Commuter rail patronage for short-haul trips was declining,
and it was assumed by the Coolidge Commission that rapid transit
could take over the facilities at a minimal cost.

5 Coolidge Commission Report 1945, p.8
6 Ibid., p.10.


Click HERE for graphic.

Ridership estimates were based upon population trends and an
assumed twelve percent ridership growth factor, derived from the
El's experience with the transit extension to Ashmont in the late

     The projects listed in the 1947 Coolidge Commission report are
a very ambitious list, effectively extending the rapid transit
network out to ten to twelve miles in all directions (see Figure C-

         Northeast:  an extension of the East Boston Line to Lynn
         North: an extension of the Elevated from Sullivan Square
          to Reading including a branch to Medford Square
         Northwest:  an extension from Lechmere to Woburn and an
          extension of the Cambridge Subway from Harvard to West
          Cambridge (Alewife) and beyond to Lexington
         West:  a second extension from West Cambridge to Waltham
          Highlands, an extension to Riverside from the Tremont
          Street Subway via the Main Line of the Boston and Albany
          Railroad, another extension to Riverside from Kenmore
          Square (forming a loop) via the Highland Branch of the
          Boston and Albany Railroad, and a branch off of the
          Highland Branch to Needham Junction and Bird's Hill
         Southwest:  two possible extensions beyond Forest Hills
          to Readville and East Dedham, plus the possible
          realignment of the Elevated to the New Haven Railroad
          tracks from Essex Street to Forest Hills
         South:  an extension to South Braintree from Savin Hill
          along the Old Colony Railroad right-of-way, and perhaps
          even further to Cohasset, Whitman and Brockton.

The total predicted cost of this program, including some changes to
the central subway between Boylston Street and Scollay Square came
to $73,375,050.  Of the many projects proposed in the Coolidge
Commission report, five have been completed, all at a smaller scale
than originally suggested:

1)   Blue Line extended to Wonderland instead of Lynn in 1952,
2)   Orange Line extended to Oak Grove instead of Reading in 1975-
3)   Red Line extended to Alewife instead of Lexington and Waltham
     in 1985,
4)   Orange Line relocated to Forest Hills in 1987 with no
     extensions beyond, and
5)   Red Line extended to Braintree instead of South Braintree or
     the extensions beyond in 1980.

     All of the cases where rapid transit lines were not extended
were a result of the recommitment to Commuter Rail which began to
take shape in the early 1970's.

     As to the reorganization of the Boston Elevated, the Coolidge
Commission recommended the establishment of a Metropolitan Transit
Authority to assume


the assets and liabilities of the El.  As in the 1926 Report, it
was suggested that the district for this Authority be expanded to
twenty-nine cities and towns (all of those within a ten mile radius
of the State House).  The proposed legislation contained within the
report formed the basis of the enabling legislation for the MTA,
enacted in August of 1947.


     Because of the comprehensive nature of the Coolidge Commission
Reports and their far-reaching expansion plans, no further planning
documents were produced during the existence of the Metropolitan
Transit Authority.  In the early 1960's, planning activities
stirred again with the Boston Regional Planning Project and the
Mass Transportation Demonstration Project.  These studies were
initiated due to the looming crisis caused by the continued decline
of commuter rail and rapid transit and the resultant deficits of
the rail companies and the MTA.  The Boston Regional Study (1963)
provided an in-depth analysis of land use and economic trends, a
comprehensive description of the existing transportation systems
including highway, public transportation and railroad, as well as
an excellent historical overview of these transportation systems. 
The Demonstration Project (1964), carried out by the Mass
Transportation Commission, was a series of experiments designed to
determine how changes in the fare structure, fare levels, and
service frequency affect patronage.  Various tests were performed
on commuter rail lines and bus lines (but not the rapid transit
system, because the experiments would have been too difficult to
perform) over a span of fifteen months, typically following this
pattern: Stage 1 reduce fares and increase service, Stage 2 -
maintain higher level of service, restore fares to pre-test levels
but institute a low off-peak fare, Stage 3 - make adjustments to
service as necessary and continue stage 2 fares.  The results of
the experiments show that increased service is more important than
lower fares in attracting new riders, but in almost all cases, not
enough new riders would be attracted to pay for the increased

     These planning studies provided much interesting information
and also helped to promote the formation of the Massachusetts Bay
Transportation Authority.  In July, 1964, the MBTA was established
by the legislature under Chapter 161A of the General Laws of the
Commonwealth.  One of the stipulated responsibilities of the MBTA
in section 18 was to "prepare and from time to time revise its
program for mass transportation.  The said program shall include a
long-range plan for construction, reconstruction or alteration of
facilities for mass transportation within the area constituting the
authority."7  The first such

7 Chapter 563 of the Acts of 1964


Click HERE for graphic.

document to be produced was the Program for Mass Transportation of
August 1966.  The MBTA was then in the process of reviewing its
expansion plans in the context of the Eastern Massachusetts
Regional Planning Project (EMRPP), and put forth in its own format
the plans for public transportation facilities which were part of
the EMRPP's comprehensive transportation planning effort.

     The method used to evaluate proposed extensions was
significantly more sophisticated than the simple population
projections used in the 1926 and 1945 studies.  The complexity was
possible due to the major data gathering effort which had taken
place in 1963 as part of the EMRPP.  The home-based travel survey
showed planners the numerous factors which go into a person's
choice of mode and thus allowed them to develop formulas and models
which would make reasonable estimations of ridership on new

     The 1966 PMT contained an Action Plan consisting of several
components with a total cost of $340 million.  Five of the projects
were extensions of rapid transit lines with the other components
pertaining to rolling stock replacement, station modernization, and
maintenance and storage facilities.  Ideas for future expansion
projects beyond the Action Plan were mentioned but not discussed in
any detail.

     Four of the five action projects have now been completed and,
in fact, have been the focus of the MBTA's construction effort from
1966 to 1987.  The recommended Haymarket North extension on the
Orange Line was completed by 1977, allowing for the demolition of
the elevated structure through Charlestown and Everett.  The second
project was the Southwest Corridor.  The 1966 PMT recommended the
replacement of the Washington Street elevated structure with a new
route along the New Haven Railroad tracks and an extension beyond
Forest Hills to West Roxbury.  The relocation of the Orange Line
was completed in 1987, but the idea of extending beyond Forest
Hills was dropped in favor of upgrading the Needham commuter rail
line.  The third project was the Harvard to Alewife extension of
the Red Line which was completed in 1985, with the modification of
a station at Davis Square in Somerville in addition to the original
proposal of stations at Porter Square and Alewife.  The Red Line
was also to be extended in the other direction to the South Shore
via the right-of-way of the former Old Colony Railroad.  The 1966
PMT suggested extending as far south as Weymouth, but it was
subsequently decided to stop at Braintree, which was accomplished
by 1980.  The final project, which has not been built to date, was
a one-mile extension of the Green line from Lechmere terminal into

     In addition to the projects, the PMT included a discussion of
its relationship to private carriers in eastern Massachusetts. 
Continuation of commuter rail service by the railroad companies was
in doubt in 1966, reflected by the use of the railroad rights-of-
way for the proposed transit extensions.  The MBTA suggested in the
PMT that commuter rail service could continue but in a


reduced form, as more of a shuttle service from outlying areas to
the ends of the rapid transit lines.  The Orange Line at Malden,
the Red Line at Alewife, and the Orange Line at Forest Hills and
West Roxbury provided good opportunities for creating cross-
platform links between railroad and rapid transit.  As for buses,
the MBTA recognized that changes would occur, with the authority
either taking over routes from private companies, subsidizing those
companies, or buying them out completely.  The PMT made no firm
plans for this but rather left the decisions up to the ongoing bus

     The final report of the EMRPP was published in January of
1969.  The MBTA had participated in the project since its inception
in 1964, although the project was done under the aegis of the
Department of Public Works (now the Massachusetts Highway
Department), specifically the DPW's Bureau of Transportation
Planning and Development.  While the MBTA had been quite
conservative in the 1966 PMT in terms of the ambitiousness of its
expansion plans, the Recommended Highway and Transit Plan provided
a forum for some longer range speculation.  The plan is divided
into three elements:  Committed Projects, the Short-range Program
(1968-1975) and the Long-range Program (1975-1990).  The list of
committed projects corresponds to the list in the 1966 PMT, but the
Short-range projects include a proposal to extend the Blue Line
from Wonderland to Pines River and the Orange Line from West
Roxbury to Route 128 in Wakefield, the Red Line from Alewife to
Route 128 in Lexington, and several changes to the Riverside line
including a connection to the Blue Line in the downtown area, a
conversion of the existing line to the high-platform rapid transit
and an extension of the line out to the Wellesley-Natik border. 
(See Figure C-4).

     These proposals all follow the pattern of extending the rapid
transit lines out to terminals along Route 128.  The fact that such
plans appear in the EMRPP report but not in the PMT is attributable
to the overall theme of the report deriving from the highway plans:
to create a complete network of transportation facilities, both
expressway and rapid transit, connecting Route 128 and the urban
core as a set of spokes between the rim of the Boston area and its
hub.  This theme is the defining characteristic of the EMRPP, even
though the transit projects recommended within it go back a long
way, most to 1945 and some to 1926.


Click HERE for graphic.


     The Boston Transportation Planning Review (BTPR) was a major
restudy of the plans laid out in the EMRPP report.  The restudy
took place in 1971-72 and marked a fundamental shift in
transportation priorities in the Boston region from highways to
public transportation.  The effect of the BTPR on transit plans was
not so much to inflate them, but rather to move them to the top of
the agenda replacing the urban expressways which had been
discarded.  The plans themselves, in fact, deflated a bit to return
to the scale of the 1966 PMT.  No extensions of the Blue line were
planned in the BTPR with instead a minor upgrading to improve
roadway access to Blue Line stations.  The Orange Line would not be
stretched north beyond Malden, although the extensions south beyond
Forest Hills to Needham and Canton were retained.  The Red Line
extension to Alewife was altered to include the Davis Square
station, and the possibility of extending to Arlington Heights was
not ruled out.  The South Shore Red Line extension was planned to
go only as far as South Quincy.  The extension of the Green Line
from Lechmere to Somerville was retained for further study, but it
was of low priority.  There was discussion of replacement service
for the Washington Street corridor in the South End and Roxbury
which would lose its rapid transit service with the demolition of
the elevated structure and relocation of the Orange Line.  No firm
plans were made as to the exact nature of the replacement service. 
Finally, there was enthusiasm for the idea of a Circumferential
Transit line (although no particular alignment was laid out), an
idea originating in 1923, but which had been absent from the
discussion for a long time.  One other non-rapid-transit element
was included in the BTPR program:  a third harbor crossing reserved
for buses, taxis, airport limousines, trucks and emergency
vehicles.  Such a special-use tunnel would encourage the use of
multiple-occupancy vehicles for access to Logan Airport.

PROGRAM (1974-1983)

     New laws were enacted at the federal level during the early
1970s concerning transportation planning in metropolitan areas. 
Specifically, federal regulations required the formation of a
Metropolitan Planning Organization to carry out continuing,
comprehensive and cooperative planning, the "Three-C" process.  As
part of this process, the MPO was required to produce a set of
documents, one of which was the Transportation Plan.  The first
Plan to be written under these new guidelines was released in July
1974.  The preparation of this document was undertaken by a group
comprised of technical staff from four agencies:  the Executive
Office of Transportation and Construction, the Metropolitan Area
Planning Council, the Massachusetts Department of Public Works and
the Massachusetts Bay Transportation Authority.


     At approximately the same time, the MBTA published the Ten
Year Transit Development Program 1974-1983.  Although this document
was not called a Program for Mass Transportation, it was
effectively a revision of the 1966 PMT which had been amended in
1968, 1969 and 1971.  The Development Program and the
Transportation Plan were the first planning documents to be
produced after the BTPR, and they clearly show the influence of the
restudy and the conclusions of its Final Report.  In terms of the
projects included in these reports, though, there is an equally
strong influence of the transit element of the Recommended Highway
and Transit Plan of the EMRPP.

     One other important event occurring at this time was the
purchase by the MBTA of the railroad rights-of-way and equipment of
the Penn Central and the Boston and Maine Railroads.  The fate of
the railroad companies had been in doubt for a long time, but the
institution of the Commuter Rail Improvement Program in 1972 gave
the MBTA the task of taking over and revitalizing the commuter rail
system.  In 1974, the transfer of property from the private
companies to the MBTA was in progress, and the MBTA was in the
process of forming a Commuter Rail Directorate in its
organizational structure.  These two documents reflect the changed
status of commuter rail by including, for the first time,
improvement projects for the railroad lines and equipment.

     For the purpose of organizing the proposals, the metropolitan
area was divided into corridors.  In the urban core area, there
were two main proposals contained in both documents:  a connection
between the Blue Line and the Green Line via a new tunnel under
Beacon Hill and the Boston Common linking Bowdoin station to the
subway under Boylston Street, and a circumferential transit line
running around the downtown area from South Station to Sullivan
Square in Charlestown.  In addition, the Transportation Plan listed
other possible improvements including a rail connection between
North Station and South Station and the restoration and
revitalization of South Station.

     In the North Shore corridor, two improvements were planned: 
an extension of the Blue Line from its terminal at Wonderland to
Lynn, Salem, or even as far north as Route 128 in Peabody, and an
upgrade of the commuter rail lines to Rockport and Ipswich.  The
northern corridor similarly has two improvements:  an extension of
the Orange Line from Oak Grove to Route 128, Reading Center or
Route I-93 at the Reading-Wilmington line, and upgrade of commuter
rail service on the New Hampshire Division through Woburn and
Wilmington.  The Orange Line extension would replace commuter rail
service from Reading to North Station, but freight service would be
retained on a third track.

     Two transit improvements were planned for the northwest
corridor:  the Red Line would be extended from Harvard through
Porter Square and Davis Square in Somerville to Alewife and perhaps
beyond to Arlington Center, Arlington Heights or Route 128 in
Lexington, and the Green Line would be


extended 1.1 miles from the Lechmere terminal to Washington Street
in Somerville.  This second project was relegated to a low priority
status when the Red Line extension was altered during the BTPR to
include the station in Davis Square.  Commuter rail service would
also be improved on the Fitchburg Division commuter rail line
including a transfer facility between the rail line and the new Red
Line extension either at Alewife or at Porter Square.

     There was only one listed improvement in the western corridor,
the reconstruction and upgrade of the tracks and facilities for the
Green Line Riverside branch and the Boston and Albany Main Line
commuter rail route from Newton to Westborough.  The southwest
corridor, on the other hand, had a number of large scale projects. 
The largest of them was the relocation of the Orange Line from the
elevated structure on Washington Street to the Penn Central (New
Haven Railroad) right-of-way to Forest Hills.  This project
included a new tunnel in the South Cove area from the Washington
Street Tunnel to the Boston and Albany right-of-way (under
construction at the time of publication of these documents), and
the removal of the railroad embankment along the Penn Central
right-of-way.  In addition to the relocation project, the Orange
Line was to be extended to West Roxbury and Needham, replacing the
existing commuter rail service on those tracks.  To replace the
service of the elevated line on Washington Street in the South End
and Roxbury, it was planned to reactivate the Green Line tunnel
under Tremont Street south of Boylston for a new light rail
extension to Roxbury, or to institute bus service including
reserved lanes.  One other project concerning the Green Line was
the connection from Brigham Circle to Brookline Village, linking
the E and D lines.  In addition to these transit projects, upgrades
for all of the commuter rail lines in this corridor were planned.

     The final corridor was the South Shore which had one main
project: the completion of the Red line extension to South
Braintree.  The extension had been built as far as Quincy Center in
1971 and the remaining segment, including two new stations was
under construction at the time.  Further extensions to Brockton,
South Weymouth or Hingham were retained for consideration.


     Between the 1966 edition of the PMT and the next version to
come out in 1978, the legislature passed a law in 19738 amending
Chapter 161A so as to transfer the responsibility for producing the
PMT from the MBTA to the Executive Office of Transportation and
Construction, which had been formed in the restructuring of
government in 1971.  EOTC undertook the revision of the PMT in late
1975, beginning a three-year process which ended with the approval
of the Revised PMT by the Advisory Board to the MBTA in December of
1978.  A great deal of analysis went into the production of this
document in terms of

8 Chapter 1140 7 of the Acts of 1973


studying the plans of the early seventies and using complex
forecasting models to determine the costs and benefits of the
various proposals.  Improved forecasting methods allowed planners
to have a better idea of future population and employment trends as
well as likely ridership levels.

     As a preliminary step to laying out the construction program
for public transportation facilities, the PMT includes an extensive
discussion of policy objectives.  Six major headings furnish the
framework for the policy of the

1)   Management - to manage the system efficiently so as to provide
     a high level of service at the minimum cost to the rider and
     the taxpayer;
2)   Ridership - to promote increased patronage of the mass transit
3)   Environment - to provide services which are beneficial to the
     environment from the standpoint of energy efficiency,
     decreased pollution, and minimized negative impacts on areas
     near transportation facilities;
4)   Economic and Physical Development - to create economic
     activity through construction projects and to promote the
     development of urban areas in the region;
5)   Transportation Service - to make the transit system as fast,
     convenient, attractive and safe as possible; and
6)   Services for Elderly and Handicapped - to increase the
     accessibility of the transit system and provide paratransit
     service where needed.

These overarching goals serve as the fundamental rationale for all
of the proposed improvements in the 1978 PMT.

     The 1978 program consisted of two segments, one for plant and
vehicle improvements and the other for service expansion.  The
first section covered such items as electric power sources for the
system, track renovations, improvements in the signaling system and
communications, maintenance and storage facilities, bus and rapid
transit vehicles, station modernization, parking capacity
expansion, and accessibility improvement projects.

     The chapter on new service projects listed fifteen proposals,
including improvements to all of the transit lines and three new
routes.  The projects are listed in counterclockwise order,
according to corridor (see Figure C-5):

    Blue Line extension from Wonderland to Lynn
    Orange Line extension from Oak Grove to Route 128
    Green Line extension from Lechmere to Tufts
    Red Line extension from Harvard to Alewife
    Green line extension to Brighton (partial rehabilitation of
     the A Line)
    Brookline Village Connector - connection between the Riverside
     Line (D) and the Arborway line (E)
    Orange Line relocation in the southwest corridor


    West Roxbury/Needham Service - either extension of the Orange
     Line from Forest Hills or major, commuter rail upgrade
    Roxbury/South End Replacement Service
    Rail service to Brockton - extension of Red Line, commuter
     rail line to Boston, railroad shuttle to Braintree, or a
     special lightweight diesel rail car joining the Red Line
     tracks in Quincy
    Commuter Boats for the South Shore
    Bowdoin-Charles Connector - connection between the Blue Line
     and the Red Line at Charles Station
    North Station Green Line Relocation - removal of the elevated
     structure over Causeway Street and reconstruct the Green Line
    North Station-South Station connector - a new rail link as
     part of the Central Artery project
    Circumferential Transit - a new transit line around the fringe
     of the Downtown Boston

     Of these fifteen projects, four have been implemented: the
Harvard Alewife extension was completed in 1985, the Orange Line
relocation was finished in 1987, the upgrade of commuter rail
service to West Roxbury and Needham opened at the same time as the
new Orange Line, and commuter boat service to Hingham has been
running since 1984 with subsidies from the MBTA.  The Old Colony
Railroad Rehabilitation is now underway (subsuming the rail service
to Brockton), and the North Station Green Line relocation is
planned to be implemented as the new North Station and Boston
Garden are built.  The Roxbury/South End replacement service, and
the Bowdoin-Charles connector are in the planning stages.  The rest
of the projects are being retained, pending a revision of the PMT.

     Following the listing of projects, the 1978 PMT had three more
chapters.  A section on low-cost capital improvements discussed
various transportation systems management (TSM) programs such as
marketing, maintenance and the promotion of carpooling, bicycling
and pedestrian travel.  Accessibility issues for senior citizens
and people with disabilities were also discussed.  A chapter
outlining the financing procedures for the capital improvements was
followed by a summary of the goals and impacts of the program,
highlighting the benefits of transit investment and some of the
land use and development changes that would occur as a result of
the implementation of the program.


     The most recent version of the Transportation Plan for the
Boston Region preceding the current update is the Fiscal Year 1983
edition.  Like the 1974 Plan, this document encompasses the entire
transportation system and discusses policy objectives for
transportation and regional development.  The projects in the Plan
are divided into four categories depending on the degree of change
to the


physical plant involved in the project.  The largest degree of
change is plant expansion, defined as "any development and
construction or acquisition of facilities or equipment for the
purpose of increasing physical capacity."9 Lesser degrees of change
are denoted as plant replacement, plant renovation and plant
enhancement.  The projects listed in these four categories
correspond to the projects in the 1978 PMT:  twelve of the fifteen
expansion projects in the PMT are included under plant expansion,
the other three are listed under plant replacement (the Orange Line
relocation, the Roxbury replacement service, and the Green
Line/North Station relocations, and the other improvements in the
PMT such as storage and maintenance facilities and other system
upgrades are distributed under plant replacement, renovation and


     Both the Transportation Plan and the Program for Mass
Transportation are now being updated, and they will both contain
some system expansion projects for the MBTA.  It is likely that
almost all of the recommended projects can be found in at least one
of the historical planning studies.  In most cases, it is clear how
the system could be expanded; the route of expansion has not
changed markedly over time.

     However, planning efforts for mass transit have changed
character over the years, as the relationship of mass transit to
the other modes of travel has been transformed.  In the early part
of the century, mass transit competed directly with commuter rail
services, while the automobile was not seen as an immediate threat. 
In the middle part of the century, rapid transit came to be seen as
a replacement for commuter rail, at least within a ten mile radius
of downtown Boston.  The automobile, meanwhile, was eating away at
the market share of both commuter rail and mass transit.  In the
1970s, rapid transit became a complement to a revitalized commuter
rail system, while both were severely threatened by the dominance
of the automobile.  In the late '80s and '90s, intermodalism has
come of age, and it is clearly recognized that mass transit is an
indispensable complement to the regional highway system.  To
facilitate the connection.between autos and transit, there has been
a great emphasis on constructing parking lots at transit stations,
and in some cases, locating new transit stations at the
intersections of rail lines and major highways.

     Changes in land use patterns have also affected mass transit
planning.  As population began to disperse in the middle part of
the century, it was thought that the rapid transit system should
reach out into the suburbs to follow.  In the 1970s, the region
realized that commuter rail could serve suburbs more efficiently
than rapid transit lines, so some of the longer rapid transit
extensions have not been pursued.  Since the BTPR, there has been a
strong policy

9 Transportation Plan FY 1983, p.49


Click HERE for graphic.

commitment to support development and commerce in the urban core. 
As a result, many transportation investments have focused on the
downtown area.

     Mass transit facilities have a very long life span.  The
initial investment is very high, but the benefits extend for many
decades.  Although Boston is a mature metropolitan area relative to
others in North America, it is still growing and developing.  The
transit system functions well, but it is not complete.  Planners
throughout the 20th Century have seen how to expand it, and
planners in the 21st Century will likely follow the same paths.


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