Assessing and Comparing Environmental Performance of Major Transit Investments (2012)

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

90 5.0 Most Promising Metrics  5.1 Summary of Most Promising Metrics This report provides information on metrics that could be used for environmental perfor- mance evaluation of transit projects. While it does not provide recommendations, the research findings do suggest some metrics that the research team concluded might be most appropriate for use in different evaluation contexts. Table 5.1 summarizes the metrics that were rated as Tier 1 or Tier 2 and are not redundant with other metrics, and identifies the scope of how the metric is calculated. Table 5.1 also identifies additional development activities that are needed before the metric is ready for use, particularly for comparing multiple projects in different regions. Three measures rated as Tier 2 in Section 4.0 were excluded from this list. Total energy and GHG emissions were excluded because the energy and GHG per passenger-mile metrics appear to be preferable for this category. Pedestrian and bicycle level of service measures from the “other” category were excluded because this issue is already evaluated qualitatively through the land use and economic development assessment. Environmental performance rating systems were excluded because they still need significant develop- ment to apply to transit, and because they may be more appropriate for agency self- assessment than for either local alternatives evaluation or national evaluation. The metrics presented here represent broad environmental performance issues of interest for comparing across projects (including benefits), rather than a detailed enumeration of all the environmental impacts considered in the environmental documentation process. The list also includes only metrics that can be computed with existing data sources and modest resource requirements, and therefore is limited in its ability to fully represent some aspects of environmental performance, as discussed below.

. 91 Table 5.1 Summary of Most Promising Metrics of Environmental Performance Performance Category Metric Scope Further Development Activities Energy and Greenhouse Gas (GHG) Emissions Operating energy or GHG emissions per passenger-mile Calculated for new project Include energy/GHG from fuel production as well as direct vehicle operations • Decide whether to use energy, GHG, or both • Develop standard energy and emis- sion factors or guidance for devel- oping project-specific factors Construction energy or GHG emissions Calculated for new project • Research required to develop models for non-materials construc- tion energy and GHG • Consider normalizing (per passenger-mile or route-mile) if used for New Starts evaluation Air Quality and Public Health Change in total project emissions Calculated for highway and transit • Determine pollutants of interest • Develop standard g/mi emission factors • Consider combined weighted index of all pollutants • Determine whether and how to include emissions from electricity generation Project air pollutant emissions per passenger-milea Calculated for transit project only Change in daily nonmotorized access trips Calculated for new project versus no-project • Validation of consistency of results among projects/models • Consider/test total nonmotorized trips accessing new project as alternative Ecology, Habitat, and Water Quality Fraction of corridor land that already is developed Project corridor (X-mile radius) • Consider categorical rating system (e.g., high, medium, low) based on quantitative benchmarks a This alternative air quality metric was considered too late in the process to fully test and compare it to other metrics. While the project team feels that project emissions per passenger-mile may be preferable to change in total emissions for informing comparative project evaluation, it will need to be more fully tested before a final judgment is made.

92  5.2 Limitations of the Metrics and the Current Evaluation Framework In addition to challenges with data acquisition and consistent calculation of certain metrics, two significant challenges were encountered in attempting to develop meaningful and reliable project-level metrics of environmental performance. First, the impacts of any individual transit project generally look small when compared on a regional basis. For the projects evaluated in this research, energy, GHG, and emis- sions changes were typically less than 0.2 percent of regional or subregional totals. The relatively small impacts were also manifested in cost-effectiveness metrics that are not favorable when compared to other air quality and GHG improvement projects on a stand- alone basis. This can lead to the potentially erroneous conclusion that the project is not worth doing. The small size of benefits reflects multiple factors: • To some extent, this is the reality of the situation – most individual transit projects make a relatively small dent in regional travel patterns and associated environmental benefits. • However, it also reflects a potentially incomplete accounting of the project’s benefits due to the current evaluation framework. This framework assumes that land use pat- terns are the same with or without the project. Secondary, longer-term benefits associated with land use changes that the transit project may induce or support, and further changes to travel patterns because of these land use changes, are not considered. • The individual project versus no-project approach also does not consider potential synergistic benefits of multiple coordinated transit projects, combined with supportive land use policies. • The poor cost-effectiveness of the transit projects when measured just on air quality or GHG effects does not account for the multiple other benefits of the project, including mobility – environmental benefits are just one of multiple reasons to undertake a transit project. The second major challenge is that it is not possible to reliably predict the secondary benefits or impacts of a transit project for ecology, habitat, and water quality. The fac- tors affecting the secondary, growth-inducing impacts of transit projects (or highway projects for that matter) are complicated and include economic/as well as policy factors and physical constraints. Models to predict the effects of transportation investments on land use patterns do exist, but they are resource-intensive to apply, and a recent evaluation for FTA found that they were not yet suitable for evaluating individual

. 93 projects, including transit projects.13 Two TCRP projects currently underway are contin- uing to investigate methods for predicting land use and economic development impacts, using very different approaches.14 Closely related to this challenge is the difficulty of quantifying benefits from projects that serve heavily built-up areas and primarily improve conditions for existing riders, rather than diverting travelers from automobiles. The environmental benefit in this situation can be characterized as a long-term strengthening of the urban core through improved travel conditions, helping attract and retain people in these settings where the environmental impacts of travel and development can be much lower. However, most current models are not well suited to forecasting the impacts of transportation improvements on metro- politan development patterns, including retaining or increasing population and jobs in urban core areas. Even if general growth patterns can be predicted, the level of detail required to assess specific environmental impacts (such as impacts to sensi- tive habitat or water quality) is generally not available. It may be that a qualitative assessment of supportive land use policies, such as FTA already performs in its assessment of the land use and economic development criteria, is the best that can be done with respect to this factor at the current time. These two challenges suggest that a different evaluation framework may be required to provide a meaningful evaluation of transit’s full environmental benefits. Specifically, this framework would assess and compare the life-cycle impacts (construction and operation) of all modes (including highways and transit) on a network or systems level. Such an assess- ment would consider differences in land use patterns that support, or would be influenced by, alternative transportation networks. In fact, multimodal, systems-level assessments have already been performed in many areas of the country as part of regional scenario planning exercises. Regional scenario planning studies have found long-term air quality and energy benefits ranging from 5 to 25 percent or more for regional scenarios of com- pact growth and transit investment, compared to business-as-usual scenarios with high- way investment.15 13 Deriving Economic Development Benefits of Transit Projects from Integrated Land Use Transportation Models: Review of Models Currently Used in the U.S. and Recommendations. Prepared by Cambridge Systematics, Inc. and Dr. John Gliebe for Federal Transit Administration, April 2009. These regional scenario evaluations could be further enhanced by incorporating life-cycle emissions and energy use (including construction, maintenance, 14 TCRP H-39: Methodology for Determining the Economic Development Impacts of Transit Investments, http://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=2364; and TCRP Project H-46, Quantifying Transit’s Impact on GHG Emissions and Energy Use: The Land Use Component http://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=3092. 15 A recent review of scenario planning studies using travel forecasting models found that land use changes, combined with supportive transit investments, were estimated to reduce metropolitan VMT by a median of 8 percent below forecast levels over a 20-year time horizon and 16 percent over a 40-year horizon. Forty-year reductions ranged from 3 to 28 percent across studies. See: Rodier, C. (2009), Review of International Modeling Literature: Transit, Land Use, and Automobile Pricing Strategies to Reduce Vehicle Miles Traveled and Greenhouse Gas Emissions, Transportation Research Record No. 2132.

94 fuel production, etc.) as better information on these factors becomes available. At a project level, evaluation could be performed by considering the consistency of the project with a regional plan that achieves substantial environmental benefits. There are admittedly many challenges to moving towards this type of evaluation. For example, the ability to do regional scenario planning that includes land use as well as transportation will vary from region to region. Land use decisions are typically made at the local (municipal) level, whereas transit planning is part of a regional process. Even if a preferred transportation and land use scenario can be developed and “adopted” at a regional scale there may be no way to ensure that it is implemented, and therefore that the full benefits of the transit project are realized. Also, to ensure consistency in methods across projects, closer attention would need to be given to the travel demand forecasting and land use assumptions across the region, rather than just the project corridor. “”A regional-scale approach, however, may be the only way to achieve a complete accounting of transit’s environmental benefits. This type of evaluation framework would also be consistent with best international practice for transportation project evaluation, as identified in the literature review for this research. In its January 2012 NPRM and pro- posed policy guidance, FTA is proposing to allow project sponsors the option of submit- ting alternative land use forecasts and associated estimates of environmental impacts, which would begin to move the process in this direction. It would still be necessary for project sponsors to evaluate individual projects on their merits. However, this evaluation might be done considering benefits that occur when the project is implemented in conjunction with other supportive projects and policies. The relative contribution of the project to the benefits of the overall regional plan might be assessed based on some factor such as ridership or passenger-miles. If this approach were taken , transit agencies might have concerns about the fact that their project is being evaluated based on factors beyond their control (i.e., regional transportation and land use decisions made by the MPO and local governments). On the other hand, this is already true within the current national land use and economic development evaluation criteria. Regional and local decisions also influence other benefits of the project, such as ridership, even within the current evaluation framework. A question that would need to be addressed is whether just the project would be evaluated, or whether the evaluation would also consider the broader regional planning context and the extent to which it supports the project.