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Transportation Impact Studies for Proposed Development: Applicant's Guide
ClickHERE for graphic. Applicant's Guide TRANSPORTATION IMPACT STUDIES FOR PROPOSED DEVELOPMENT Prepared for: Division of Planning Department of Metropolitan Development City of Indianapolis By: Barton-Aschman Associates, Inc. Dallas, Texas September, 1990 Officially Adopted by MDC Resolution 90-R-38 September 5, 1990 TABLE OF CONTENTS Page I. FOREWORD. . . . . . . . . . . . . . . . . . . . . . . . . . . 1 II. INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . 3 Purpose of Transportation Impact Studies. . . . . . . . . . . 4 Benefits to the Community . . . . . . . . . . . . . . . . . . 4 Impacts On Staff Review Time. . . . . . . . . . . . . . . . . 5 Purpose of the Applicant's Guide. . . . . . . . . . . . . . . 5 Ill. WHEN TO PROVIDE A TRANSPORTATION IMPACT STUDY . . . . . . . . 7 Study Warrants for a Complete Transportation Impact Study . . 7 High Traffic Impact Areas . . . . . . . . . . . . . . . . . . 8 Study Warrants for a Traffic Operations Analysis. . . . . . . 8 IV. PREPARER/REVIEWER QUALIFICATIONS. . . . . . . . . . . . . . . 9 Preparer Qualifications . . . . . . . . . . . . . . . . . . . 9 Reviewer Qualifications . . . . . . . . . . . . . . . . . . . 9 Department Responsibilities . . . . . . . . . . . . . . . . . 9 V. TRANSPORTATION IMPACT STUDY PROCESS . . . . . . . . . . . . .11 VI. STUDY AREA. . . . . . . . . . . . . . . . . . . . . . . . . .14 Minimum Study Area. . . . . . . . . . . . . . . . . . . . . .14 Additional Study Area . . . . . . . . . . . . . . . . . . . .14 High Traffic Impact Areas . . . . . . . . . . . . . . . . . .14 VII. STUDY HORIZON YEARS AND TIME PERIODS TO BE ANALYZED. . .16 Study Horizon Years . . . . . . . . . . . . . . . . . . . . .16 Time Periods. . . . . . . . . . . . . . . . . . . . . . . . .16 VIII. DEVELOPMENT TO BE ANALYZED . . . . . . . . . . . . . . .18 Site Development. . . . . . . . . . . . . . . . . . . . . . .18 Non-Site Within Study Area. . . . . . . . . . . . . . . . . .18 IX. NON-SITE TRAFFIC ANALYSIS. . . . . . . . . . . . . . . .19 Components to be Considered . . . . . . . . . . . . . . . . .19 Methodology . . . . . . . . . . . . . . . . . . . . . . . . .19 Alternate Methodology . . . . . . . . . . . . . . . . . . . .21 Non-Site Traffic Analysis and Necessary Improvements. . . . .21 X. TRIP GENERATION ESTIMATION. . . . . . . . . . . . . . . . .22 i Acceptable Data Sources . . . . . . . . . . . . . . . . . . .22 XI. TRAFFIC DISTRIBUTION AND ASSIGNMENT. . . . . . . . . . . . . .23 Acceptable Distribution Procedures. . . . . . . . . . . . . .23 Assignment Procedures . . . . . . . . . . . . . . . . . . . .23 Pass-by and Diverted Trips. . . . . . . . . . . . . . . . . .24 Internal Trips. . . . . . . . . . . . . . . . . . . . . . . .24 XII. CAPACITY AND OTHER ANALYSES . . . . . . . . . . . . . . . . .25 Capacity and Level of Service . . . . . . . . . . . . . . . .25 Level-of-Service. . . . . . . . . . . . . . . . . . . . . . .25 Other Analyses. . . . . . . . . . . . . . . . . . . . . . . .27 XIII. RECOMMENDATIONS. . . . . . . . . . . . . . . . . . . . . . .28 Report Documentation. . . . . . . . . . . . . . . . . . . . .29 XIV. PUBLIC RECORD . . . . . . . . . . . . . . . . . . . . . . . .30 APPENDIX: TENTATIVE SUPPLEMENTAL REVIEW PROCESS. . . . . . . . . . 1 ii LIST OF TABLES Page Table 12.1 Level of Service Description for Signalized Intersections . . . . . . . . . . . . . . . . . . . . . . . . . .26 Table 12.2 Level of Service Description for Unsignalized Intersections. . . . . . . . . . . . . . . . . . . . . . . . . . .26 LIST OF FIGURES Page Figure 5.1 Transportation Study Process. . . . . . . . . . . .13 iii I. FOREWORD In the past 10 years, the Indianapolis Urbanized Area has experienced significant growth. This growth is most noticeable around regional shopping centers and along major arterials forming commercial corridors. Like many other urbanized areas, this development was approved one project at a time. The cumulative impact of this development has caused significant demand on portions of the area's transportation system. Considerable concern with the area's infrastructure not keeping pace with approved development was repeatedly expressed in town hall meetings held by Mayor Hudnut in 1987. In response to the community's concern, the Department of Metropolitan Development, Division of Planning and Department of Transportation began requesting transportation impact studies (TIS) for proposed development meeting certain thresholds. Those studies analyzed proposed development in the context of the larger surrounding developing area. The City has continued to request transportation impact studies and has found them to be effective decision making tools. In 1988, to provide consistency, the Department of Metropolitan Development, Division of Planning developed a set of interim guidelines for requesting and preparing transportation impact studies. This Applicant's Guide and a more detailed Procedure Manual replace the interim guidelines as the Metropolitan Development Commission's policy in regards to requirements for transportation impact and traffic operations studies. This Applicant's Guide and the Procedure Manual were developed with the assistance of a Study Advisory Committee including traffic consultants, developers, neighborhood representatives and other appropriate government agencies. These members were: Eli Bloom, NORA Community Council, Inc. Daniel Buck, Indiana Department of Transportation Bruce Deason, Builders Association of Greater Indianapolis Robert Falk, Duke Associates William Fehribach, Consulting Engineers of Indiana, Inc. Don Hargadon, NORA Community Council, Inc. John Hart, Jr., Eaton & Louth Rebecca Hopewell, Chamber of Commerce Chuck Kiphart, Hamilton County Planning Commission James Nuttal, Winchester Village Neighborhood Association Michael Quinn, Clark, Quinn, Moses & Clark David Stroud, Johnson County Plan Commission John Van Buskirk, Stark, Doninger, Memitz & Smith Clay Whitmire, Indiana Department of Transportation Also serving on the Advisory Committee representing City Departments were: Ron Greiwe, Department of Transportation Steve Lains, DMD, Division of Development Services Eugene Lausch, DMD Deputy Director Stuart Reller, DMD, Division of Planning John Willen, Department of Transportation Sweson Yang, DMD, Division of Planning 2 II. INTRODUCTION The metropolitan government of Indianapolis - Marion County is responsible for ensuring the public health, safety and welfare associated with new development and redevelopment. Under the authority granted by state law and local ordinances, the Department of Metropolitan Development and the Department of Transportation may identify a need for and request a transportation impact study. The two departments collaborate closely throughout the transportation study process. Specifically, the Department of Metropolitan Development takes the lead regarding study requirements, planning and land use implications while the Department of Transportation has responsibility regarding traffic engineering operations and safety. The purpose of this guide is to provide consistency and predictability in the request, preparation, and review of transportation impact studies (TIS). While much of the guide is stated in terms of requirements and procedures to be used, the guide also includes recommendations to assist preparers and reviewers to complete their work in the most efficient and timely manner possible. This guide has been officially adopted by the Metropolitan Development Commission as a part of its Rules and Procedures. City Legal has determined that the Metropolitan Development Commission may request submittal of a transportation impact study from a petitioner for a rezoning or plan approval without an amendment to existing ordinances or state laws. The City has determined it to be appropriate to request, as opposed to require, transportation impact studies for certain rezoning, variance and plan approval petitions. (This is consistent with the Tentative Supplemental Review Process outlined in the Appendix of this document.) If the applicant elects to go to hearing without complying with the City's request, the City will either prepare a transportation impact study assuming a worse case scenario or render an opinion based on available information. A request for a transportation impact study indicates to the Metropolitan Development Commission (or Hearing-Examiner) that transportation is a critical issue in the subject petition. At the time of this writing, the City has procedures in place for identifying the need for transportation impact studies relative to rezoning, variances, and plan approval petitions. These guidelines recognize that on occasion the City may identify the need for a transportation impact study relative to a development proposal other than one of these requests. However, at the time of this writing, the City has no procedures for systematically reviewing permit applications relative to a need for a transportation impact study. Therefore, it is recommended that the City investigate the desirability of establishing procedures for extending transportation impact studies to the permit process. This investigation is beyond the scope of these guidelines. 3 PURPOSE OF TRANSPORTATION IMPACT STUDIES The Indianapolis Urbanized Area strives to provide a high level of mobility to support a desirable quality of life and encourage a vibrant economy. Limitations on financial resources and right-of- way availability are limiting the capability of the City and State to continue expanding roadway capacity. The metropolitan government has established a comprehensive planning process by which the ultimate land use and transportation plan are adopted and revised. This plan, as amended, has guided development for more than two decades. Because of ultimate roadway expansion limitations and the community's desire to maintain a high quality of mobility, proposals to intensify development and increase traffic flow are evaluated prior to approval to accomplish the following purposes: 1. To determine if proposed development can be accommodated within the existing or planned transportation system capacity along with other development reflected in the Comprehensive Plan, 2. To identify improvements beyond those already anticipated which are needed to satisfactorily accommodate the proposed development, and 3. To determine how developments of significant size, including those consistent with the Comprehensive Plan, should be provided access so as not to adversely affect traffic operations or safety near the site. BENEFITS TO THE COMMUNITY Transportation impact studies benefit the metropolitan area by: 1. Providing decision makers with a basis by which to assess transportation implications of approving proposed zoning changes and development applications 2. Aiding in keeping current its short and long range plans 3. Providing a basis for assessing existing or future localized transportation system deficiencies which should be improved 4. Addressing transportation-related issues associated with development proposals that may be of concern to neighboring residents, businesses, and property owners 4 5. Providing a basis for negotiations for improvements and funding participation in conjunction with a development or zoning application or petition. Transportation impact studies provide an objective assessment of both the anticipated impacts and needs of the proposed development. Requirements for transportation impact studies have been instituted in recent years by cities and counties throughout the United States. Most major cities experiencing significant growth have transportation impact study requirements. The trend has been toward increasing requirements as a basis for both assessing the extent of transportation impacts and negotiating funding for needed improvements. Some communities require transportation impact studies for nearly every development larger than a few single family residences; others vary according to local policies and conditions. IMPACTS ON STAFF REVIEW TIME The City currently requests transportation impact studies in conjunction with zoning requests for developments meeting the study warrants described in the following chapter. It also requests traffic operations analyses for certain permit applications. The procedures in this report are intended more to promote consistency among studies and procedures than to expand the size of the reports. As a result, it is anticipated that the typical review times for a TIS will remain similar to those which currently exist; they should even be reduced in the long run as consistency in assumptions, methodology, and format becomes accepted practice among preparers. PURPOSE OF THE APPLICANTS GUIDE The purpose of this guide is to: 1. Provide consistency in the request, preparation, and review of transportation impact studies and traffic operations analyses 2. Ensure that critical transportation and development issues are addressed 3. Provide staff with guidance and a checklist in the review process 4. Promote increased understanding of transportation impact issues among those involved in the development process. Topics addressed in this Applicant's Guide include: 1. When to provide a transportation impact study 2. TIS study area 3. Preparer/reviewer qualifications 4. Transportation impact study process 5 5. Time periods to be analyzed 6. Development to be analyzed 7. Analysis horizon years 8. Trip generation estimation 9. Background traffic estimates 10. Traffic distribution and assignment 11. Intersection capacity analysis methodology More detailed procedure information is provided in the Procedure Manual For Transportation Impact Studies For Proposed Development, which is available from the Department of Metropolitan Development, Division of Planning. 6 III. WHEN TO PROVIDE A TRANSPORTATION IMPACT STUDY The need for a transportation impact study or traffic operations analysis may be identified by the Department of Metropolitan Development (DMD) or the Department of Transportation (DOT) when rezoning, variance or plan approval petitions are filed. A traffic operations analysis may be requested as part of a complete transportation impact study or for petitions which do not meet the warrants for a complete impact study. Examples of traffic operations analyses include: 1 . Study of proposed driveway locations, resulting sight distances, and adequacy of proposed queuing provisions. 2. Accident experience and safety analysis. 3. Traffic signal warrant and progression analysis. Although the DOP and DOT currently have no procedures for systematically reviewing permit applications to identify the need for a transportation impact study, these guidelines recognize that on occasion the City may identify the need for a transportation impact study or traffic operations analysis in response to a permit application. STUDY WARRANTS FOR A COMPLETE TRANSPORTATION STUDY A complete transportation impact study (as described in subsequent chapters of this document) may be requested for any proposed development that meets criterion A and either criterion B or C (or both): A. Significantly Sized Project A development meets this criterion if it contains 150 or more single-family residential units or if it generates 100 or more peak hour trips in the peak direction. B. Nearby Congestion A development meets this criterion if the proposed development is expected to significantly impact surrounding roadways, intersections, or sets of intersections which are already operating at level-of-service "D" or worse during any hour which is selected by the DOP/DOT for analysis. The level of service will be determined by an analysis prescribed in the current edition of the Highway Capacity Manual (Transportation Research Board) using data that reflects the current traffic condition. 7 C. Modifications to Roadways This criterion is met when the proposed development is expected by the DOP or DOT to significantly impact a roadway segment identified in the City's Transportation Improvement Program for improvements. This criterion is also met when the proposed development includes modifications to the roadway system, other than curb cuts or deceleration/acceleration lanes. HIGH TRAFFIC IMPACT AREAS The DMD has designated certain areas within Marion County as high traffic impact areas. Such designation reflects special sensitivity to traffic condition changes due to existing congestion, problematic circulation patterns, burgeoning traffic operations problems, or other traffic conditions of special concern. A transportation impact study may be requested for any proposed new development or modifications to existing development within the high traffic impact areas. DOP maintains the most recent map showing the boundaries of high traffic impact areas. STUDY WARRANTS FOR A TRAFFIC OPERATIONS ANALYSIS: A traffic operations analysis may be requested for any of the following conditions: A. requests for a driveway(s) on any frontage road, arterial, or collector street B. requests or probable need for a new traffic signal to control driveway(s) or street(s) serving a proposed or existing development C. existing sight distance limitations or high accident experience adjacent to a site. 8 IV. PREPARER/REVIEWER QUALIFICATIONS PREPARER QUALIFICATIONS Transportation impact studies shall be prepared by professionals with training and experience in traffic engineering and under the supervision of a registered professional engineer with training and experience in traffic engineering (operations and safety analysis experience). The Department of Metropolitan Development and Department of Transportation require that the responsible registered professional engineer sign and seal the study report. REVIEWER QUALIFICATIONS A transportation impact study shall be reviewed by one or more members of the professional staffs of the DMD, Division of Planning (DOP) and Department of Transportation (DOT) who collectively have training and experience in traffic impact study methodology, land use planning, and traffic engineering, including traffic safety and operations. DEPARTMENT RESPONSIBILITIES The Department of Metropolitan Development is the lead agency regarding study requirements, long, range transportation planning issues, land use issues, and traffic projections while the Department of Transportation has the primary responsibility regarding street design requirements, traffic engineering operations and safety. The DOP will be responsible for coordinating the TIS study process. DOP reviewers will have the primary responsibility for reviewing the following: - study methodology - future land-use projections - trip generation - trip distribution - trip assignment - long-range transportation forecast/planning 9 DOT reviewers will be responsible for the following: - sight distance and other safety aspects - accident experience and mitigation proposals - access locations and provisions - geometric changes to existing roadways - traffic control-related topics. The DOP and DOT will both have the responsibility for the following: - Determine whether or not a proposed development requires a transportation impact study or traffic operations analysis in conjunction with a request for a development-related approval. - Determine the type of study required. - Meet with study preparer to identify study issues, needs, assumptions, procedures, available sources of data, past and related studies, report requirements, and other topics relevant to study requirements. - Provide to the preparer available relevant data from agency files, including traffic counts, improvement plans and programs, accident records, traffic signal information, transportation and comprehensive plan information and reports, data on development planned or approved within the study area, relevant city ordinances, regulations and policies, and other information directly relevant to the required study. This information shall be provided at a cost not to exceed the cost of reproducing the necessary materials. - Review the capacity analysis. 10 V. TRANSPORTATION IMPACT STUDY REVIEW PROCESS It is intended that the formalized study review process assist study preparers to develop their reports in the most efficient and responsive manner possible. It is specifically not intended that the process be either cumbersome or induce unnecessary delay to the development review process. It is also intended to answer the following questions: 1. Is a TIS warranted? 2. Is there an agreement on study area, horizon year, scope, and report contents? (This is accomplished in an initial meeting between the preparer and the reviewers.) 3. Is there agreement on methods and technique for analysis? Are they adequate? 4. Are findings and recommendations reasonable and acceptable? 5. Should the staff recommend approval or denial based on professional guidelines, city policies, and regulations? Figure 5.1 summarizes the transportation study process employed by the Department of Metropolitan Development and Department of Transportation. Figure 5.1 also shows how the transportation impact study process becomes part of the tentative supplemental review process when applicable. The City's tentative supplemental review process is briefly described in the Appendix. Depending on the type of development, there will be either five or six required review steps involved in the study process: 1. Determination of whether or not a traffic study will be required. 2. Initial meeting between preparer and reviewers to discuss study issues, scope, assumptions, data and data sources, technical procedures, and desired report contents. 3. Preparation (by applicant) and approval (by reviewer) of a Memorandum of Understanding which details the assumptions and methodologies to be used. 11 4. Formal transportation study review by Department of Metropolitan Development/ Department of Transportation. 5. (If DMD supplemental review process is required) Additional review in conjunction with other components of supplemental review process. 6. Approval or denial of the development petition or application. 12 Click HERE for graphic. FIGURE 5.1 TRANSPORTATION STUDY PROCESS 13 VI. STUDY AREA MINIMUM STUDY AREA Any complete transportation study analyzing off-site access needs and impacts will include at least all site access points and major intersections (signalized and unsignalized) adjacent to the site. ADDITIONAL STUDY AREA Beyond this basic area, DMD/DOT will determine any additional area to be included based on local or site-specific deficiencies, development size, traffic conditions, or local policy potentially affected by the proposed development. The study area will also encompass vacant parcels of land believed to impact the intersections being analyzed, so as to analyze the proposed project in the context of other previously approved or anticipated developments in the surrounding area. Generally the study area must be large enough to encompass the critical intersections to be analyzed and the vacant land, which once developed, is believed to have a significant impact upon them. The Department of Metropolitan Development, Division of Planning shall identify and provide land use projections for vacant parcels within the study area. HIGH TRAFFIC IMPACT AREAS The DMD has designated certain areas within Marion County as high traffic impact areas. Such designation reflects special sensitivity to traffic condition changes due to existing congestion, problematic circulation patterns, burgeoning traffic operations problems, or other traffic conditions of special concern. The DOP maintains the most recent map showing the boundaries of high traffic impact areas. The study area for any proposed development within a designated high traffic impact area will include the entire designated high traffic impact area in addition to the study area that would be normally defined. The entire high traffic impact area is included in order to capture the cumulative impact of future development within this area. 14 Because of the magnitude of effort required to prepare the non-site traffic estimates for high impact areas, it is the intention of DOP to provide this information. DOP will provide traffic volume estimates for TIS horizon years covering development projected for all vacant parcels under the comprehensive plan. 15 VII. STUDY HORIZON YEARS AND TIME PERIODS TO BE ANALYZED STUDY HORIZON YEARS Transportation impact studies are to address conditions in the current year plus the anticipated completion year of the proposed development assuming full build-out and occupancy. If the proposed development is to be implemented in phases, it may be appropriate to analyze each major phase (i.e., initial phase, one intermediate phase, and full project buildout). Additional horizon years, ranging from a minimum of 10 years after the study date to a maximum of full build-out of the defined study area, will be required. TIS for developments located in high traffic impact areas or developments which will significantly impact the interstate highway system are to be based on a full build- out condition. TIME PERIODS TO BE ANALYZED For each defined horizon year specific time periods are to be analyzed. In most cases only analyses of street peak hours will be required. However, land use classifications which experience their highest trip generation levels during periods other than street peak hours may require analyses for such periods to determine proper site access and turn lane storage requirements. Traffic signal warrant studies normally require determination of the highest eight hours of traffic volumes during a day; as a result, longer time periods are needed for these analyses. In some instances, analysis of a different time period may be appropriate to assess site access needs or traffic signal needs rather than traffic impacts on the adjacent street system. For proposed developments located in high traffic impact areas, analysis of a time period other than and in addition to weekday street peak hours may be appropriate. Examples of land use classifications which typically have substantially higher site trip generation peaks at times other than weekday street peak hours are: - shopping centers (Saturday afternoon) - discount stores (Saturday afternoon) - recreational uses (e.g., theaters, zoos, theme parks, stadiums, arenas) (various times) - restaurants (usually Friday or Saturday evenings) 16 - schools (at start and finish time) - churches (on Sundays or Saturdays, before and after largest service) - garden centers (on weekends) The analysis time period should be discussed and designated by the DOP/DOT reviewers in the initial meeting. However, analysis of transportation impacts should always include weekday A.M. and P.M. street peak hours if the proposed developments generate significant activity during these periods. 17 VIII. DEVELOPMENT TO BE ANALYZED The total anticipated transportation infrastructure needs in the study horizon year(s) are needed so the City can accurately evaluate implications associated with the applicant's request for development approval. However, the impacts and infrastructure needs will be assessed separately for the baseline condition (horizon year development excluding site) and total development (site plus non-site development). SITE DEVELOPMENT Development proposed to be located on the site under study should be categorized by specific land use type consistent with classifications contained in the latest edition of Trip Generation (Institute of Transportation Engineers). The proposed number of development (building) units (e.g., gross square feet of building area, dwelling units, hotel rooms, etc.) should be provided. Land area is insufficient to provide a basis for analysis. If the proposed land-use or density is inconsistent with the Comprehensive Plan recommendation, comparison of the proposed land use and the Comprehensive Plan recommendation should be made using classifications contained in the Trip Generation report. NON-SITE WITHIN STUDY AREA The impacts of the anticipated non-site development should be assessed separately from those of the proposed development to aid both the City and applicant to determine sources of transportation infrastructure needs. All significant developments within the study area that have been approved or are likely to occur by the specific horizon years should be identified and incorporated into the study. The land-use type and magnitude of the probable future developments in the horizon years should be identified in conversations with the DOP staff. 18 IX. NON-SITE TRAFFIC ANALYSIS Traffic having neither an origin from nor destination to the subject site is considered "non-site traffic". For any horizon year, non-site traffic volumes are estimated to characterize the base conditions for the area of study -- that is, the traffic volume conditions of the study area in the horizon year, assuming the subject site is not developed or redeveloped. The purpose of the non-site traffic analyses is to determine: 1. What are existing conditions and what improvements will be needed to alleviate current deficiencies? 2. What will conditions be in the horizon year(s) without the site under study being developed, and what improvements are needed? 3. What additional improvements will be needed in the horizon year(s) to meet the additional needs generated by the proposed development of the study site? COMPONENTS TO BE CONSIDERED Two components need to be considered when estimating non-site traffic volumes. They are: Through traffic. This consists of trips which have neither an origin nor destination in the study area. These t,-Lips begin and end at points external to the study area; however, their paths are within the study area. Traffic generated by other developments within the study area. These trips have either an origin, a destination, or both in the study area. METHODOLOGY Non-site traffic volumes should be developed using the "build-up" method. This method will typically provide accurate and easily traced results. The concept consists of forecasting peakhour traffic to be generated by approved and anticipated developments in the study area, estimating growth in through traffic generated outside the study area, and adding both to existing traffic in the study area. If the subject site is being redeveloped, existing site traffic is subtracted from this total to provide the estimate of future non-site traffic. The general procedure to be followed in developing non-site traffic is given below: 19 1. Assess impacts of transportation system changes on study area travel patterns. Transportation system improvements that are programmed, committed, or deemed highly likely to be in place by the horizon year should be identified in conversations with the DMD/DOT reviewers. Where applicable, the impact of transit service changes on modal split should be considered. This applies to both existing and committed transit service. 2. Identify study area developments to occur e@fore horizon year. All significant developments within the study area that have been approved or are likely to occur should be identified and incorporated into the study. The land-use type and magnitude of the probable future developments in the horizon year should be identified in conversations with the DOP staff. 3. Estimate Trip Generation. Using techniques consistent with the Trip Generation section of this document, estimate the peak hour trip generation for each of the developments identified in Step 2. 4. Estimate directional trip distribution. Consistent with the procedures presented in the Traffic Distribution and Assignment section of this document, develop the directional distribution of traffic for each identified development from Step 2. 5. Assign traffic. Once the traffic for the probable developments within the study area is generated and distributed, assign it to the horizon year study area roadway network using procedures presented in the Traffic Distribution and Assignment section of this document. 6. Estimate through traffic growth. Recent growth trends in traffic volumes through the entire study area should be used to estimate the growth in traffic having both trip ends outside the study area. These growth rates should be obtained from or discussed with the DOP/DOT reviewers. They should be applied to an estimate of existing through traffic. As an alternative, DOP may provide an estimate of through traffic based on travel forecasts prepared by the DOP or the petitioner can conduct a license plate study as part of the transportation impact study to determine current through traffic. The approach to defining through traffic will be discussed at the initial meeting with DOP/DOT. 7. Sum study area and through traffic. Add the results of Steps 5 and 6 to yield total non-site traffic volume projections for the horizon year. 8. Review results for reasonableness. The preparer should review the results for reasonableness of the proposed final projection of non-site traffic. 20 A more specific step by step explanation of the above procedure is provided in the more detailed procedure manual available from the Department of Metropolitan Development, Division of Planning. ALTERNATE METHODOLOGY For study horizons using the adopted transportation plan horizon year, the DOP/DOT staff may, at its discretion, require that travel simulation modelling forecasts be used to replace or supplement the "build-up" method to estimate non-site traffic. NON-SITE TRAFFIC ANALYSIS AND NECESSARY IMPROVEMENTS Once the non-site traffic volumes have been estimated, an analysis of the future base conditions should begin. This will provide an assessment of the traffic operations and needed improvements in the horizon years without the subject development in place. With the base conditions established, the impact of the subject site can be measured. Analysis procedures should be consistent with those described in the Analyses section of this document. Improvements necessary to accommodate the non-site traffic in the horizon year at the design level of service (discussed in a later chapter) should be determined. It is very important to research and identify improvements that have already been committed by other developments. Additional improvements needed to alleviate existing high accident experience or solve other traffic-related problems or deficiencies should be identified. Documentation should clearly state that these improvements are needed to satisfy base conditions -- without the development being proposed -- and that the need for them is not generated by the proposed development of the site under study. 21 X. TRIP GENERATION ESTIMATION Trip generation is the process of estimating the amount of traffic to be generated by a subject development. This is usually done through the use of rates or equations expressed in terms of units of development (i.e., per dwelling unit or per thousand feet of building floor area). ACCEPTABLE DATA SOURCES Several data sources and methods for estimating trips generated by a development are available: 1. Institute of Transportation Engineers (ITE) Trip Generation report (latest edition) containing data from observations around the country for over 20 years. 2. Prior local (Indianapolis area) studies which have been made for various reasons, but which are applicable for the purpose of estimating trip generation for site development. These studies should be approved by the DOP reviewer prior to being used. 3. Prior studies made outside the Indianapolis area for a similar land use. These studies should only be used if they are approved in advance by the DOP reviewer. 4. Special studies conducted especially for the study at hand. Developments surveyed should be representative of the development for which the trip generation estimate is to be made. These should be local if similar developments exist and can be isolated for proper surveys. They may be made out of town if no adequate local examples can be surveyed. Proper procedures should be used. Study sites should be approved in advance by the DOP reviewer. 5. A combination of the above, adding local data to the ITE data, or combining local or special study data. Additions to ITE data should be plotted on the scatter diagram provided in the latest edition of Trip Generation, if available, to check for consistency. Combination of data from different sources should be approved in advance by the DOP reviewer. 22 XI. TRAFFIC DISTRIBUTION AND ASSIGNMENT After the trip generation analysis for the proposed development has been completed, the traffic must be distributed and assigned to the roadway system for the impacts to be determined. The trip distribution process estimates the off-site origins and destinations of the generated trips. The assignment process produces estimates of the amount of site traffic that will use each route in the study area. ACCEPTABLE DISTRIBUTION PROCEDURES The directions from which traffic will approach and depart the site can vary depending on several location-specific factors, including: Size of the proposed development Type of the proposed development Surrounding and, in some cases, competing land uses, population, and employment distributions Prevailing conditions on the existing street system To help in the distribution of traffic, an influence area (area within which most site trips are made) may be defined. The influence area should be large enough to include most of the trip ends attracted to the site. Ideally, an existing market study could be used to establish the influence area. However, if no market study exists, the influence area should be established and documented based on a reasonable estimate. ASSIGNMENT PROCEDURES Traffic assignments should consider logical routings, available and projected roadway capacities, and travel times. Often multiple path assignments should be made to account for spreading of traffic among different routes with similar travel times. Realistic estimates should be made of traffic diverting to avoid horizon year congestion if any is expected. Assignments should consider transportation improvements projected to be in place by the analysis year. Existing trip distribution data from actual sites within the immediate vicinity may be used for the purpose of making traffic assignments. It is important to remember that if the site is a redevelopment project, assigned traffic generated b the old or existing development should first be subtracted to avoid "double counting". 23 PASS-BY TRIPS Many land uses (e.g., retail and restaurant) not only generate new vehicle trips, but also attract trips that were already passing by in the traffic stream and are simply attracted to the subject site. These trips, commonly referred to as pass-by trips, are captured from a traffic stream that moves past the site. The procedures described in the ITE Trip Generation report should be used to account for these trips. Locally collected data as well as current research may also be used in determining these values if approved by DOP or DOT. INTERNAL TRIPS Very little data has been collected locally or elsewhere to quantify the extent of internal trip making within a mixed use development. Common current practice is to consider internal trip reductions only where mixed use developments consisting of at least two major complementary uses exists. This includes such complementary use combinations as office-retail, office-hotel, office-residential, retail-residential, and office-restaurant. Other combinations may be considered. Reductions for internal trip making will only be accepted if based on actual surveys of similar developments and approved by DOP or DOT. 24 XII. CAPACITY AND OTHER ANALYSES Several analyses are applicable to derive the study findings, conclusions, and recommendations. Measurements of the capacity conditions at critical locations within the study area are the primary means of estimating traffic impacts. Site access, safety, traffic control, geometric, and parking should also be considered. CAPACITY ANALYSIS Capacity analyses should be performed at all proposed site access locations and all intersections adjacent to the subject site. Other critical or currently congested segments of the network within the study area may also be identified for analysis at the discretion of the DOP/DOT reviewers. Elements such as freeway weaving sections, ramps, parking facility access points, and site access vehicular storage reservoirs are examples. For each horizon year, the capacity analyses should be conducted for conditions with and without the proposed development to determine the incremental impacts of the project and the improvements necessary to support each phase of the development. The latest edition of the Highway Capacity Manual, published by the Transportation Research Board, is to be used for performing all capacity analyses. However, the results of any capacity analysis does not replace the need for professional engineering judgement, but rather provides additional information from which to partially base such judgement. Careful review of the numbers and a field check of the location are very important. LEVEL OF SERVICE The standard criterion used to define quality of traffic flow is "level of service" (LOS). This is a qualitative assessment of factors such as speed, volume, geometry, delays, and ease of maneuvering. LOS can be quantified in different ways depending on the focus of the analysis. For instance, LOS for signalized intersections is based on average stopped delay time per vehicle, while unsignalized intersection LOS is based on critical gaps and estimated reserve capacity, and freeway ramp LOS is based on the capacities of the ramp lane(s) and the freeway main lanes. All analysis techniques specify the quality of operations as a letter (see Tables 12.1 and 12.2). 25 TABLE 12.1 LEVEL OF SERVICE DESCRIPTION FOR SIGNALIZED INTERSECTIONS =================================================================== Level of Service Qualitative Description ------------------------------------------------------------------- A Good Progression, few stops, and short cycle lengths B Good progression and/or short cycle lengths; more vehicle stops. C Fair progression and/or longer cycle lengths, some cycle failures; significant portion of vehicles must stop. D Congestion becomes noticeable; high volume-to- capacity ratio, longer delays, noticeable cycle failures. E At or beyond limit of acceptable delay; poor progression, long cycles, high volumes, long queues. F Unacceptable to driver. Arrival volumes greater than discharge capacity; long cycle lengths, unstable/unpredictable flows. ---------------------- SOURCE: Highway Capacity Manual, Special Report 209, Transportation Research Board, Washington, D.C. 1985 ___________________________________________________________________ TABLE 12.2 LEVEL OF SERVICE DESCRIPTION FOR UNSIGNALIZED INTERSECTIONS =================================================================== Level of Service Reserve Capacity Impact on Minor (peph) Street Traffic A ò 400 Little or no delay B 300-399 Short traffic delays C 200-299 Average traffic delays D 100-199 Long traffic delays E 0-99 Very long traffic delays F * * _______________________________ SOURCE: Highway Capacity Manual, Special Report 209, Transportation Research Board, Washington, D.C. 1985 peph = passenger cars per hour * When demand volume exceeds the capacity of the lane, extreme delays will be encountered with queuing, which may cause severe congestion affecting other traffic movements in the intersection. This condition usually warrants improvement to the intersection. 26 The minimum acceptable LOS (design level) in the City of Indianapolis is "D". Analyses should show an intersection LOS of D or better to be acceptable. Anything below D for an intersection is considered unacceptable. If the analyses shows that conditions With only non-site traffic will result in a level of service below "D", the preparer should document this finding and ascertain the level of improvement needed to maintain at least the base level of service once site traffic is added. OTHER ANALYSES Additional analyses may be needed depending on the characteristics of the proposed development its impacts, and the transportation system within the study area. These analyses will be stipulated by the DOP/ DOT and may include traffic control, traffic signal warrant or progression studies, accident analyses, geometric feasibility of recommended improvements, sight distance, parking, or other analyses appropriate to the particular situation. In all cases specific site access shall be proposed. Analyses should identify the baseline conditions and impacts of off-site growth during the horizon period without the proposed development as well as conditions with the proposed development together with a statement of the impacts and needs generated by the proposed development. The study report should state the findings of all analyses and provide conclusions. 27 XIII. RECOMMENDATIONS Recommendations should be developed to address the conclusions resulting from the analyses of the proposed development's access needs and impacts on the transportation system. Recommendations should be grouped into two categories: site-specific recommendations and non- site recommendations. Recommendations should address feasible transportation system improvements needed to satisfactorily accommodate site and non-site traffic, respectively (identify these separately). The recommendations should reflect improvements currently planned or programmed by any public or private agency. Recommendations may include improvement scheduling that could beneficially be changed. Transportation facility improvements can be classified as either major structural improvements, such as the widening of roadways, or operational improvements, such as installing a traffic signal or changing lane usage. It is important to view recommendations for improvements within appropriate time perspectives. Recommendations should be sensitive to the following issues: - Timing of short-range and long-range network improvements that are already committed and scheduled. - Anticipated time schedule of adjacent developments. - Size and timing of individual phases of the proposed development. - Logical sequencing of various improvements or segments - Right-of-way needs and availability of additional right- of-way within the appropriate time frames. - Local priorities for transportation improvements and funding. - Cost-effectiveness of implementing improvements at a given stage of development. - Necessary lead time for additional design and construction. Since improvements can often be implemented in more than one order, the recommendation should address an implementation sequence that would provide maximum compatibility with the 28 overall roadway system configuration needed for network effectiveness. REPORT All transportation impact studies and traffic operations analyses will be documented in a report. The report will describe: - proposed development - existing conditions - study procedures - data collected - findings of analyses - conclusions and recommendations Reports should be complete but concise. Letter or memorandum reports may be acceptable for studies of limited scope. All reports will be reviewed by DOP and DOT; those requiring additional information or revision will be discussed with the preparer and returned for revisions. 29 XIV. PUBLIC RECORD Transportation impact studies, including both reports and data, become public record upon submittal. Information contained in these submittals may be used by agency staffs or other study preparers in subsequent studies. The original sources of reused information should be cited when taken from prior submittals. 30 APPENDIX TENTATIVE SUPPLEMENTAL REVIEW PROCESS Step 1. Petition Submittal ù Preliminary review and assessment of the appropriateness of the use of Supplemental Review on the petition, as filed. Time: Approximately one week. Step 2. Meeting with Petitioner, Neighborhood Organization, and City Agencies ù Description of the project by the petitioner and his representatives. ù Input from neighborhood organization. ù Determination by City staff if Supplemental Review is actually called for by the petition. ù Definition by City staff of the scope of additional information or analysis required for proper review of the petition. ù Petitioner may decide to schedule a public hearing at any time during this step. Time: Approximately one to two weeks. Step 3. Petitioner Prepares Requested Additional Information or Analysis for Submittal Time: Unspecified time, as required by the petitioner. Step 4. Review o Additional Information or Analysis by City Staff, Development of Findings Time: Two weeks, unless submittal is deemed deficient in scope within five days by reviewing agency. Step 5. Negotiations with Petitioner Time: Unspecified time, as required by the petitioner. Petitioner may decide to schedule a public hearing at any time during this step. 31 Step 6. Scheduling of Public Hearing; Preparation of Staff Comments Time: At least 23 days prior to public hearing for individual notice; one week prior to the hearing for staff comments. Step 7. Public Hearing by the Metropolitan Development Commission ù Petitioner may elect to have an initial hearing by the Hearing Examiner rather than the full Metropolitan Development Commission. 32 ELECTED OFFICIALS William H. Hudnut, III, Mayor City-County Council Dr. Philip Borst, 25 Ray R. Irvin, 21 Rozelle Boyd, 11 Paul H. Jones, 10 David M. Brooks, At Large David P. McGrath, 20 Richard F. Clark, 13 Mary Bridget Moriarity, 15 Dwight Cottingham, 18 Beverly Mukes-Gaither, AL Beulah Coughenour, 24 Stuart W. Rodes, 7 Carlton E. Curry, At Large William G. Schneider, 3 William A. Dowden, 4 Julius F. Shaw, At Large Allen L. Durnil, 14 Beurt R. SerVaas, 2 Kenneth W. Giffin, 19 John Solenberg, 5 Gordon C. Gilmer, 1 Betty Ruhmkorff, 12 Jeff Golc, 17 Stanley P. Strader, 23 Harold Hawkins, 16 Steven R. West, 6 Holley M. Holmes, 8 Susan Williams, 22 Glenn L. Howard, 9 METROPOLITAN DEVELOPMENT METROPOLITAN DEVELOPMENT COMMISSION: James Wade, Jr., President Lois J. Horth Dr. Lehman D. Adams, Jr., DDS Mary Ann Mills Edward Buckley Michael W. Rodman James J. Curtis Larry Tindall Donald F. Elliott DEPARTMENT OF METROPOLITAN DEVELOPMENT M. D. Higbee, Director Stuart Reller, Administrator, Division of Planning PROJECT COORDINATION Clarke Kahlo, Deputy Administrator Sweson Yang, Principal Planner Michael Peoni, Senior Planner Steve Cunningham, Senior Planner Jeff Nawrot, Planner Natalie Graves, Secretary Ned Wissel, Secretary Phil Pettit, Supervisor, Drafting and Reproduction Ken Pearcy, Print Shop Manager George Jacobs, Printer Burton Carter, Printer
