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40 New tools for transportation decision making incorpo- the framework, performance measures were identified in the rate environmental considerations and facilitate environ- areas of energy, materials, and waste. These are discussed at mental performance measurement. Numerous tools already the end of this section. incorporate environmental performance measures into trans- portation planning, design, construction, maintenance, and operations (Schwartz, 2006; Amekudzi and Meyer, 2005). Envi- Ecosystems, Habitat, and Biodiversity ronmental Management Systems (EMS) and related Environ- mental Information Management Systems (EIMS) are used to Highways can cause direct loss of habitat resulting from road support the NEPA process, track commitments, and manage construction; fragmentation and isolation of existing habi- public involvement (Cambridge Systematics, Inc., forthcoming; tats; obstacles that limit migration and dispersal and create Cambridge Systematics, Inc. et al., 2006). Remote sensing equip- smaller, more inbred populations; and animal-vehicle colli- ment and Geographic Information Systems (GIS) facilitate sions resulting in wildlife mortality and a serious safety con- data collection, analysis, and reporting (Muller et al., 2007; cern for the traveling public. Recent work in this area focuses Thieman, 2007; Donaldson and Weber, 2006). On-line statewide on the way an entire ecosystem works, rather than narrowly GIS repositories are making a variety of previously unavailable examining impacts on individual species. In general, three datasets known to transportation planners, including air qual- broad objectives are considered in this area: ity, endangered species, wetlands, and water quality data (VIGN, 2007; WiscLINC, 2007). Maintain or improve ecological functions of potentially affected ecosystems or habitat areas; Minimize harm to wildlife species; and Environmental Performance Protect native plant communities. Factors and Measures Environmental impacts of highway capacity projects have Table 5.1 presents four broad performance measures to traditionally been addressed through the National Environ- address these objectives and specific applications of each mental Policy Act (NEPA) process, parallel state processes, performance measure. The case study highlight illustrates and related federal and state regulations. These efforts focus how Arizona's Wildlife Linkage Program measures loss of on minimizing the impacts of new or expanded infrastruc- habitats. ture through modifications to specific alignments and mitigation of those impacts that cannot be avoided. These efforts have typically focused narrowly on the transportation Water Quality right-of-way, but recent federal and state efforts are shifting how environmental factors are addressed by: 1) consider- Considering the effects of highway capacity on water resources ing the relationship between transportation and the natu- can help protect water resources and also ecosystems, bio- ral environment more broadly, with a focus on protecting diversity, wildlife habitat, and endangered or sensitive species and enhancing quality environmental areas, rather than that rely on healthy aquatic ecosystems. Water quality protec- mitigating the impacts of specific projects; and 2) under- tion has historically been considered after project sites have standing and addressing environmental factors starting at been selected, but there is growing support for considering the earliest stages of project development, especially long- water quality protection much earlier in the planning process, range planning. Six performance factors have been identi- before environmental and permitting processes are required. fied within the environmental element of the framework, Recent work in this area focuses on a watershed approach that including: considers the functions of individual water bodies in an over- all system. Ecosystems, Habitat, and Biodiversity; Water Quality; Maintain and improve water quality; and Wetlands; Minimize indirect impacts on water quality at watershed Air Quality; scale. Environmental Health; and Climate Change. Table 5.2 presents eight broad performance measures to address these objectives and specific applications of each per- Each of these factors is discussed below in more detail, formance measure. The case study highlight illustrates how including specific performance measures and applications of Colorado's I-70 Mountain Corridor Tier 1 EIS captures the those measures. In addition, though not directly applicable to impact of highway capacity projects on water quality.

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41 SHRP 2 Framework Measure Specific Measure Applications Loss of Habitats Impact of transportation Acres of fragmented or threatened habitat in the state or region; construction on degradation in quality and Change in number of acres of a specific habitat; quantity of land essential to the survival of target plant or animal species. Change in composition and structure of habitat; Change in the amount of habitat edge (locations where habitat stops or starts); Change in the acreage of interior habitat; Distance of habitat fragments from each other; Preservation of high-quality wildlife habitat (wetlands, old-growth forests, etc.); Number of projects that protect sensitive species or restores habitat; Number of acres of priority conservation areas acres protected annually; Sustained population ecology (increased size and density of species, balanced age and sex structure, reduced mortality, new growth, etc.); and Population size of indicator species. Natural Resource Plan Consistency Consistency Project contributes to the goals and objectives identified in the natural resource plan. between natural resource plans and Project sponsor has coordinated with local natural resource agency to align project transportation project plans. with goals and objectives. Project has expected impacts on high-priority sensitive natural resources as identi- fied in a natural resource plan. Is ecosystem protection incorporated into the agency/authority's strategic planning as an articulated goal or objective? Have existing ecosystem protection and related efforts (e.g., habitat conservations plans) been identified and screened for relevancy? Number of state highway miles with up-to-date natural resource maps relative to total that need mapping. Animal-Vehicle Collisions Impact of Number of vehicle collisions with animals listed on the endangered species list; and transportation projects on the number and Change in animal-vehicle collisions. characteristics of collisions between animals and vehicles. Losses of Native Plants Impact of transportation Losses of Native Plants Impact of transportation construction on the quality and construction on the quality and quantity of native quantity of native plant communities: plant communities. Change in health and diversity of native plant community; Change in acres of native plants relative to nonnative plants; Change in acres of invasive plants within highway corridor right-of-way; Percent of native vegetation preserved; Number of acres with newly planted native plants; Acres sprayed with herbicide; Total square feet of noxious weed infestation, per 0.10-mile section; and Total square feet of nuisance vegetation, per 0.10-mile section. Case Study Highlight: Arizona's Wildlife Linkage Assessment Description: The purpose of this effort is to identify critical habitat connectivity areas and potential linkage zones that are important to Arizona's wildlife and natural ecosystems. Nine public agencies and nonprofit organizations collaborated to produce an assessment document and map which provide a first step toward identifying large blocks of protected habitat, potential wildlife movement corridors through and between them, the factors that could possibly disrupt these linkage zones, and opportunities for conservation. The non-binding document and map serves as an informational resource to planners and engineers, providing suggestions for the incorporation of these linkage zones into their management planning to address wildlife connectivity at an early stage of the process. Sample Measure: Each transportation project is evaluated in the context of the Wildlife Linkage Assessment, and what the probable impact will be. The Assessment provides a common reference point for all projects under consideration. Table 5.1. Environmental Measures Ecosystems, Biodiversity, and Habitat Factor

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42 SHRP 2 Framework Measure Specific Measure Applications Water Quality Protection Areas Impact of transportation Degree of intrusion of transportation infrastructure into water quality protec- construction on priority water quality protection area. tion area; Proximity of transportation projects to receiving waters; Proximity of transportation projects to water bodies with established TMDLs; Change in pollutant loadings for nutrients; Expected pollutant emissions from construction and operation of new trans- portation infrastructure; and Percent of water samples collected that meet state quality standards for clarity when working in water. Hydromodification Impact of transportation construction Extent of modification of a water body as a result of new capacity investment on water quality due to the alteration of water bodies by (significant, minor, none); transportation projects. Change in sediment load (predicted or observed); Change in nutrient load (predicted or observed); Change in temperature (predicted or observed); Change in velocity on receiving water body (predicted or observed); Degree of steam bank and shoreline erosion (predicted or observed); and Number of culverts retrofitted for fish passage, number of barriers removed at major construction projects. Losses of Riparian and Floodplain Areas Impact of Change in acres of riparian areas; transportation construction on the quality, quantity, location, Acres of riparian areas disturbed or degraded; and functioning of the areas adjacent to the affected water bodies that strongly influence water quality. Acres of riparian areas improved; Change in ecological function of riparian areas impacted by a capacity investment; Amount of watershed improvement achieved after five or more years through appropriate measures; and Acres of open space land protected from development. Water Resource Plan Consistency Consistency between Project contributes to the goals and objectives identified in the watershed water resources and watershed management plans and management plan; transportation project plans. Project sponsor has coordinated with local water resource agency to align project with goals and objectives; and Project has expected impacts on high-priority sensitive water resources as identified in a water resource plan. Construction-Related Water Quality Impacts Impacts on Change in turbidity due to construction activities; water quality due to highway construction. Change in sediment loads due to construction activities; Change in pollutant loads due to construction activities; Quantity of dredged material disposed at various sites (ocean, coastal waters) and used for various purposes (wetlands creation); and Percent of surface waters degraded from highway development projects. Water Quality Standards Compliance Consistency of Project impact on TMDLs and water quality standards for specific water transportation project-related water quality impacts with bodies; water quality standards. Available pollutant loads prior to exceeding allowable thresholds; and Average pollutant concentrations of various metals, suspended solids, and toxic organics in road runoff. Table 5.2. Environmental Measures Water Quality Factor

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43 SHRP 2 Framework Measure Specific Measure Applications Highway Runoff Change in water quality due to added Change in pollutant loads due to change in highway capacity based highway capacity. on VMT; Change in pollutant loads due to change in highway capacity based on new lane-miles; Proximity of new road to receiving waters; Percentage of urea (deicing compound) discharged directly to surface waters; Pollutant loads during "first flush" events; Quantity of oil and grease loading via road runoff; River miles, lakes, and ocean shore miles impaired by urban runoff (not just highways); Amount of road salts generated per VMT or per lane-mile; and Per capita vehicle fluid losses. Impervious Surface Impact on watershed water quality due Increase in impervious surfaces due to direct facility construction; and to additional buildings, roads, and other impervious surfaces Increase in impervious surfaces due to development induced by facility built as a result of added transportation capacity. construction. Case Study Highlight: Colorado I-70 Mountain Corridor Tier 1 EIS Description: The Colorado DOT (CDOT) has undertaken a Programmatic EIS to identify solutions for the I-70 Mountain Corridor between Denver and Glenwood Springs. The PEIS examined the indirect impacts of alternatives, including land use and development patterns, and the resulting impact on various environmental indicators. Environmental areas addressed include wildlife movement and habitat, threatened and endangered species, vegetation, wetlands, riparian areas, fishery resources, streams, winter maintenance, stormwater runoff, land use, growth effects, eco- nomic effects, visual resources, recreation resources, historic properties, air quality, noise, geologic hazards, regulated material and mining waste, environmental justice, and public lands (4(f) properties). Sample Measures: For each alternative the following issues were considered: Water quality issues from winter maintenance activities and impact of stormwater runoff Measured in sediment, suspended solids, phosphorus, sodium chloride; Identified water quality impaired streams and TMDLs Measured in sediment; Identified water supply sources (including drinking and public water supplies Measured in sediment, phosphorous, chloride; Issues associated with stream stability hydraulic function, and stream health Measured in instream flow requirements, ammonia, sediment, temperature, dissolved oxygen; Issues associated with spills or release of hazardous materials associated with transport on I-70 Measured in various possible types of spills; and Identified antidegradation standards, nonpoint, and point sources Measured in nutrients, ammonia, phosphorus, suspended sediment, instream flows, dissolved metals, chloride, dissolved oxygen, temperature. Table 5.2. (Continued). Wetlands and not solely quantity, in project planning and programming processes. Wetlands are complex ecosystems that, depending on their type and on circumstances within a watershed, can improve Minimize taking of wetlands; and water quality, provide natural flood control, diminish droughts, Enhance ecological integrity by minimizing impacts to recharge groundwater aquifers, and stabilize shorelines. They high-quality wetlands. are vital to both water quality and ecosystem function. Regu- lated by the Clean Water Act, wetlands can be addressed by Table 5.3 presents three broad performance measures to the watershed and ecosystem approaches identified under address these objectives and specific applications of each per- the water quality and ecosystems factors. There has been a formance measure. The case study highlight illustrates how recent move toward the consideration of wetlands quality, the Washington State DOT's Transportation Project Mitigation

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44 SHRP 2 Framework Measure Specific Measure Applications Ratio of Wetland Acres Taken and Replaced Annual Annual acreage of wetlands destroyed versus wetlands created. impact of transportation construction on statewide amount of wetlands lost compared to new wetlands built. Losses of High-Quality Wetlands Impact of transportation Change in acreage of high-quality wetlands; construction on high-value wetlands. Expected change in ecological function of wetlands as a result of mitigation for capacity investments; and Ecological value of wetlands impacted by a capacity investment. Wetlands Plan Consistency Consistency between Project contributes to the goals and objectives identified in the wetlands plan; wetlands plans and transportation project plans. Project sponsor has coordinated with local wetlands (or natural resource) agency to align project with goals and objectives; and Project has expected impacts on high-quality wetlands as identified in a wetlands plan. Case Study Highlight: Washington DOT Transportation Project Mitigation Cost Screening Matrix Description: The Transportation Project Mitigation Cost Screening Matrix or "screening tool" is a tool that helps transportation planners identify proposed projects that may benefit from the application of watershed-based mitigation. The screening tool analyzes readily-available data on urbanization, floodplain areas, soil types, topography, wetlands, hazardous materials, parks, and other cultural resources. Projects that encounter these features commonly have the highest environmental mitigation costs, especially for stormwater treatment and wetlands replace- ment. The tool generates a "mitigation risk index" or "MRI" consisting of a single score that estimates the percentage of land area within the project limits that will likely experience logistical difficulties or elevated costs for in right-of-way environmental mitigation. Specific to wetlands mitigation, the tool includes a "Potential Wetland Restoration Site Environmental Benefits Ranking Criteria." Sample Measures: Site has extensive hydrologic alteration Loss of hydrology can mean the total conversion of the site from wetland to upland. Sites with exten- sive hydrologic alteration have the greatest potential to restore many of the recognized wetland functions. Site has extensive vegetation alteration Sites with extensive forest clearing have potential to restore some flood storage/flow control, water quality, temperature maintenance, and organic export functions. More than 50 percent of site has Hydric Code A or B soils Site has increased potential for providing groundwater recharge function. Site has surface hydrology connection to river/stream improve site's ability to provide impacted functions and priorities from City Comprehensive Plans. One point if site has surface water connection, 2 points for regular surface water flooding, and 1 additional point if the site's stream reach supports fish species. Table 5.3. Environmental Measures Wetlands Factor Cost Screening Matrix is used to measure the losses of high- Table 5.4 presents two broad performance measures to quality wetlands. address these objectives and specific applications of each per- formance measure. The case study highlight illustrates how carbon monoxide and particulate matter concentrations are Air Quality measured in the Minnesota DOT's 2003 Statewide Trans- Clean Air and transportation legislation has required the inte- portation Plan. gration of the transportation and air quality planning processes since 1970. This integration is intended to ensure that trans- Climate Change portation decisions are consistent with the air quality goals for a region. Current requirements include the transporta- Climate change should be addressed both in terms of trans- tion conformity process, which requires that projects within portation impacts on the climate, and the potential impacts transportation improvement programs do not exceed air of climate change on transportation infrastructure. A con- quality standards for an area. formity process, similar to what is used for other emissions, may suggest a method to address transportation's impacts on Meet National Ambient Air Quality Standards; and climate change. Research suggests that climate change will Reduce carbon monoxide and particulate matter hotspot significantly impact transportation infrastructure through violations. rising sea levels and related changes.