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CHAPTER 4
TOOLS AND METHODS FOR CONSIDERING ENVIRONMENTAL FACTORS
INTRODUCTION basis for the updated Regional Policy Plan). Two studies of
environmentally sensitive areas, the Outer Cape Capacity
As noted in Chapter 3, identifying the location and sever- Study and the Monomoy Capacity Study concluded that both
ity of potential environmental problems is one of the key parts of Cape Cod were severely constrained by a lack of
challenges facing efforts to consider environmental factors in available transportation infrastructure and water supply. Pro-
transportation systems planning. However, rapid advances in jected build-out of developable land was projected to create
computer technology and database management capabilities a more serious situation. Management options identified in
have led to new tools and methods being available to plan- the studies included the identification and protection of envi-
ners and engineers. This chapter examines tools either being ronmentally sensitive areas such as future well sites; poten-
used or being considered for use. The first section discusses tial zoning changes and land acquisition; transit and travel
the results of the survey and case studies as they pertain to demand management strategies; and the purchase or ease-
tools and methods used to consider the environment in plan- ments of sensitive resource areas to protect habitat and open
ning. Next, recent and ongoing research is reviewed to space.
discuss emerging tools for addressing the environment in One aspect of the Outer Cape Capacity Study that was
systems planning. The chapter concludes with a discussion directly aimed at bringing environmental considerations into
of the methods and tools being used in strategic environ- transportation planning early in the process was the use of an
mental assessments (SEAs) overseas. environmental sensitivity index. The intent of this index was
to identify the amount and proximity of environmental
resources to critical transportation facilities. The index was a
COMMONLY USED TOOLS AND METHODS
sum of weighted scores assigned to four environmental
The results of the DOT and MPO surveys indicate that the resources--wetlands/surface water bodies, rare species habi-
most commonly used tools for considering environmental tat, rare plant habitat, and critical upland areas. The index
factors in transportation planning are was applied to Route 6, the major highway serving the length
of Cape Cod. A 100-meter band on each side of Route 6 was
· Data trend analysis, established as a required boundary. A score for each resource
· Geographic information systems (GIS) and overlay was given on the basis of the distance from the centerline of
mapping, the road. A score of 100 was assigned if the centerline passed
· Socioeconomic/community impact assessment methods, directly through the resource; the score decreased linearly
· Public or expert surveys, with distance in the bandwidth. The indices for each of the
· Focus groups, and four resource areas were then averaged to determine the envi-
· Environmental impact models (specifically, air quality ronmental sensitivity of the surrounding environment for
impact models). Route 6. Figure 16 shows the locations along Route 6 having
varying degrees of environmental sensitivity. Wider bands
The case studies provide a detailed look at typical or indicate greater sensitivity.
evolving tools for environmental analysis in transportation
systems planning. Some of the more notable approaches are
described below. Florida Department of Transportation
FDOT's efficient transportation decision-making (ETDM)
Cape Cod Commission process is one of the most advanced in the United States,
especially when considering the level of technical support that
During the 1990s, the Cape Cod Commission developed a has been provided to make the ETDM process successful.
methodology for examining the environmental capacity lim- As noted in Chapter 3, the foundation of the ETDM
its of selected geographic areas of Cape Cod (this formed the process is the Environmental Screening Tool. This Internet-
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Figure 16. Environmental sensitivity index, Cape Cod.
based GIS application provides several key capabilities to the resource information is provided by the responsible
process. environmental agencies.
· Standardized Analyses--Standardized analyses have
· Data Input--The Environmental Screening Tool allows been developed by environmental resource agencies
those responsible for transportation studies or projects and are automatically performed by the Environmental
(i.e., FDOT or the MPOs) to input and update informa- Screening Tool. For example, the tool compares the
tion about the proposed actions. The primary data that location of proposed projects with known locations of
are input relate to environmental resource information environmentally sensitive resources. Where possible,
and project planning information. Environmental quantitative information is provided to the user of the
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tool (e.g., how many acres of wetland could possibly be Comments must be submitted to an ETDM coordinator
affected?). Data can be displayed in tabular form or in who acts as a gatekeeper for the information that is
various graphical forms. The environmental resource placed in the database.
agency representative to the ETDM process is notified
when new data is received from a project sponsor. The The Environmental Screening Tool is used in both the sys-
agency is then given 45 days to conduct any direct, sec- tem planning and programming processes to expedite the
ondary, or cumulative impact analyses on the resource exchange of information concerning potential transportation
for which it is responsible. investments or specific projects. Figure 17 shows where the
· Summary of Comments--The Environmental Screen- screening tool fits into both the planning process and the pro-
ing Tool collects the comments from ETDM partici- gramming decision process. Typical planning summary
pants and provides a summary of all agency comments reports include
and recommendations. In particular, agency comments
associated with key issues are highlighted, especially · Project description,
those relating to the Purpose and Need Statement, the · Purpose and Need Statement,
degree of effect of the proposed action, project scoping · Agency comments,
recommendations (including recommendations for · GIS mapping,
additional technical studies), and a running summary · Secondary and cumulative impacts evaluations,
of comments received at public meetings during the · Public involvement comments, and
project development process. · Preliminary project concept based on agency and pub-
· Read-Only Public Access--The general public is lic input.
granted general access to only some components of the
database. Accessible information includes such things Programming summary reports include the following
as project description, summary impact graphics, and information:
previously submitted comments. As configured, the
Environmental Screening Tool will not allow public · Project description and logical termini,
comments to be directly entered into the system. · Purpose and Need Statement,
Figure 17. FDOT screening tool in planning and programming.
Source: Florida Department of Transportation, 2002 (77).
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· Class of action determination, giving up legislatively mandated review powers. Trial runs of
· Agency comments, the system, however, have been so successful that it seems
· Comments from affected community, likely that all resource agencies will eventually participate.
· Preliminary project concept, Approximately $1 million has been spent on the system to
· Required technical studies to achieve NEPA compli- date. FDOT will be working with MPOs over the next sev-
ance and project permit, eral years to put in place the technology and staff training that
· Reasonable alternatives for further study, will be necessary to operate the system in the regions.
· Dismissed alternatives (including reasons for dis- The initial FDOT assessment of the ETDM process is that
missal), and it permits the identification of critical environmental issues
· Dispute resolution issues. early in the process; can narrow the scope of project plans,
specifications, and estimates; eliminates the involvement of
As shown, the summary reports provide a comprehensive agencies that do not have to be involved in the process; main-
overview of the relevant information concerning possible tains a continuous record of the information provided by key
environmental impacts. participants in the process; establishes a basis for permitting;
FDOT is developing agency operating agreements that out- and provides up-to-date information to the public. The down-
line the responsibilities of those who will participate in the side is that additional staff work needs to occur earlier in the
process. In particular, these agreements relate to the types of process and a substantial investment in technology is needed
information that will be provided by each participant, the to keep the process running. However, FDOT officials
reviews that will be conducted, and the steps that will be taken strongly believe that the positive long-term benefits of this
by signatory agencies to undertake required environmental process will far outweigh the short-term costs.
analyses. Some resource agencies are still uncertain about Figure 18 shows some of the Environmental Screening
participating in this process because of their concern about Tool screens available on the system.
a Identifying the Wetlands Inventory
Figure 18. Using the FDOT Environmental Screening Tool.
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b Identifying Wetlands by Type
c Focusing on Wetlands at Particular Site
Figure 18. (Continued) Using the FDOT Environmental Screening Tool.
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d Wetlands by Type in Selected Area
e Project Record
Figure 18. (Continued) Using the FDOT Environmental Screening Tool.
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f Summary of Impact: Acres of Wetlands Affected
g Purpose and Need Statement
Figure 18. (Continued) Using the FDOT Environmental Screening Tool.
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Maryland Department of Transportation perform assessments and field studies for several hun-
dred projects each year ranging in size and scope from
MDOT uses various approaches to better integrate envi- minor traffic management and control studies to large
ronmental concerns into its planning and decision-making capacity improvement projects. From 1995 to 1999
activities, including for example, SHA archaeologists performed 1,750
assessments.
· Secondary and Cumulative Effects Analysis (SCEA)-- · Aesthetics--The SHA is involved in several beautifica-
MDOT has developed procedures for considering sec- tion initiatives. A wildflower program was introduced
ondary and cumulative effects of proposed projects in in 1991 when the SHA adopted a reduced mowing pol-
compliance with the NEPA process and Council of icy to encourage the growth of native wildflowers. The
Environmental Quality (CEQ) regulations. They have SHA also has initiated an extensive urban highway
worked closely with local agencies in developing a reconstruction program called Streetscapes. Projects
methodology based on an expert panel review of land- under this program are conducted in partnership with
use data to determine what these effects will likely be in local communities and include enhanced amenities as
major transportation corridors (84). sidewalks, landscaping, drainage improvement, and
· Storm Water Management--The SHA's stormwater traffic management.
management program is one of the first and most com- · Wetlands--For each highway project in project devel-
prehensive efforts of any highway agency in the coun- opment, the SHA develops an extensive inventory of
try. To prevent the adverse effects of storm water natural resources within the study corridor including all
runoff, the state has developed 14 performance stan- wetlands and waterways. The SHA attempts to select
dards for development sites. the roadway alternative having the least effect on these
· Erosion and Sediment Control--To protect the Chesa- resources. While in the past it was common to see 10 or
peake Bay, Maryland has enacted sediment control more wetland acres affected by a typical highway proj-
requirements for all construction projects. The SHA's ect, in the last decade, several projects have had less
sediment control program has been adopted by many than 1 or 2 wetland acres affected.
DOTs.
· Stream Restoration--The SHA engages in watershed
Minnesota Department of Transportation
planning with the U.S. Army Corps of Engineers, local
jurisdictions, and MPOs on a project-by-project basis. Although Mn/DOT has developed one of the most com-
Detailed technical analyses are performed to support prehensive processes for considering environmental factors
watershed planning. In the last decade, there has been a in systems planning, this process relies on more traditional
strong national emphasis on restoring impacted or analysis tools to identify problem areas. As noted by
degraded streams using natural channel design. The Mn/DOT officials, the types of tools used are specific to the
SHA has used this technique extensively. types of environmental issues being faced. For example,
· Parkland and Forest Conservation--The SHA has environmental justice analyses are based on census data that
worked closely with conservation agencies and groups relates transportation services provided to different popula-
to develop procedures for environmentally sensitive tion groups. For the natural environment, a GIS called
design and construction. As part of the design process, MnModel divides the state into 20-acre squares, with 27 lay-
for example, consideration is given to saving trees des-
ers of information associated with each square. Mn/DOT
ignated as "specimen" or "significant." Road align-
officials believe this model has strong potential for identify-
ments have been shifted to avoid such trees in several
ing archaeological and historic sites, sensitive soils, slopes,
cases.
and water resources that would be critical for the types envi-
· Cultural Resources Program--The SHA has a staff of
ronmental systems planning they envision.
professional architectural historians to ensure that his-
torical resources are considered during the planning and
design process for proposed highway projects. The Pima County (Tucson), Arizona
SHA is developing a preservation plan for historic high-
way bridges to ensure the continued effective use of his- One of the most extensive examples of identifying sensi-
toric bridges. tive ecosystem and human habitats before developing a com-
· Archaeological Resource Protection--Similar to cul- prehensive plan is found in Tucson. The Sonoran Desert
tural resources, the SHA employs professional archae- Conservation Plan is a strategy adopted by Pima County to
ologists to ensure that archaeological resources are preserve critically sensitive areas of the desert, of which
considered during the planning and deign process of Pima County occupies six million acres, in the face of
proposed highway projects. Working in close coordina- expected substantial growth (85). With an estimated 7 to 10
tion with architectural historians, SHA's archaeologists square miles of desert lost to urbanization every year, the
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plan was undertaken to precede the efforts to update the · Critical and sensitive habitats and biological corridors
county's comprehensive plan so that important strategies identified in the plan supported 39 species that needed
could be incorporated into the investment and policy direc- protection. The key to the analysis was the importance
tions that would result from this latter effort. of interconnectivity of the habitats that supported
As noted in the draft plan, "The original purpose of the these species. The multispecies conservation plan has
conservation plan is to logically plan for continued commu- become a very important point of departure for the
nity growth and expansion without significant adverse reg- development of the county's comprehensive plan and,
ulatory consequences from enforcement of the Federal in particular, for identifying the areas where develop-
Endangered Species Act." In other words, what could the ment should be avoided.
county do to avoid federal regulatory constraints on the
future growth in the region? However, as the plan was being With a determination of the acreage necessary to stabilize
developed, local officials found that understanding the sen- endangered species, along with targeted historic and cultural
sitive ecosystem of the desert and the public interest in pro- reserves, Pima County planners are able to identify environ-
viding protection of this resource for future generations mentally sensitive lands (ESLs) that will be protected from
resulted in the plan becoming "a form of growth manage- development pressures. In addition, guidelines have been
ment plan that will guide future urban growth and expansion developed that provide road designers with strategies to min-
by ecosystem-based planning guidelines." Local officials imize impacts to the environment along designated environ-
expect that the principles and strategies espoused in this mentally sensitive roadways (ESRs). Figure 19 illustrates the
conservation plan will carry strong weight in the delibera- approach that was taken by Pima County planning staff in
tions associated with updating the county's more general conducting the resource analysis for the Sonoran Desert.
comprehensive plan.
The Pima County Board of Supervisors is spearheading
this effort, coordinating with 12 government land manage- San Francisco Bay Area
ment agencies and a 74-person steering committee. Steering
committee members represent a wide range of interests, from The Metropolitan Transportation Commission (MTC) has
environmental advocates to development interests. an active program of initiatives and planning efforts aimed at
Five critical areas were identified for detailed assessment. providing environmentally sustainable development and
transportation system performance in the region. Some of the
· Ranch conservation lands were intended to preserve MTC's more innovative efforts include the following:
sufficient land to support ranching. As noted in the plan,
"ranching is a significant land use that has served to pro- · Addressing Equity in Transportation Planning and Ser-
tect our natural open space, and it continues to be an vice Provision--Many of the programs in the regional
important traditional industry that has shaped the rural transportation plan (RTP) focus on equitable access to
landscape." transportation services for people with low incomes or
· Cultural and historic resources are an important element who are elderly or disabled. The RTP is subject to an
of the Sonoran Desert. Although only 12% of the tar- environmental justice (EJ) analysis to assess the distrib-
geted land area had been surveyed by the publication of utive impacts of the plan. Equity analysis for the RTP
the plan, over 4,000 archaeological and historic sites includes an explicit evaluation of the benefits and bur-
had been catalogued. The plan identified the most criti- dens of the transportation plan on minority and low-
cal parts of the desert that should be targeted for historic income communities. Other MTC efforts on this topic
preservation. include the development of transportation solutions for
· Mountain parks have been one of the most important those transitioning from Welfare to Work, the Trans-
natural resources in the Pima County Region. Since portation for Livable Communities Fund that helps re-
1998, when the conservation plan was first proposed, vitalize some of the region's most disadvantaged com-
over 135,000 acres of Bureau of Land Management land munities, the Low-Income Flexible Transportation
has been conserved. The plan identifies potential loca- Program, and other efforts to improve the availability
tions for further conservation efforts. and affordability of transportation options. As part of its
· Riparian (or water) resources are considered the most equity review, the RTP defines a Lifeline Transit Net-
threatened and vulnerable by the conservation plan. The work, including transit routes, service levels, and costs.
threat includes not only contamination and draw-downs The system addresses both spatial and temporal service
of surface waters, but also the lowering of groundwater gaps in providing low-income and minority populations
levels. The plan identifies opportunities where riparian with access to major services at a reasonable level of ser-
systems can be enhanced and preserved not only to pro- vice. The MTC also performs project-level EJ analysis.
vide water, but also to secure future recreational and · Corridor-Level Planning--MTC has identified 16
park lands. multimodal corridors in the Bay Area that are the most
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Resource Potential Threats
Distribution and Stressors
Level of Threat Existing
Management
Gaps in Conservation Additional Conservation
Management Measures
Protected Sites and
Landscapes
Figure 19. Resource analysis methodology for the Sonoran Desert Conservation Plan.
Source: Pima County, 2000 (85).
traveled routes on the region's rail, highway, and Washington State Department of
bridge networks. These 16 corridors are the focus of Transportation
many planning activities. For each corridor, manage-
ment objectives are defined for improving the levels of WSDOT officials are undertaking several initiatives
transportation service on all modes, and associated designed to integrate environmental considerations into
environmental impacts are assessed. For example, agency operations. These include
management objectives for the Golden Gate Corridor
include the following: · Environmental Benefit/Cost Assessment System--
WSDOT has been particularly concerned about inter-
Minimize travel times for HOV and transit in entire nalizing the externalities of transportation decisions and
corridor; is developing an approach for environmental benefit/
Develop ramp metering for US101 to balance access cost assessment. This system is expected to improve
for local and through trips; transportation project delivery by enabling agency offi-
Expand commute period transit options in corridor, and cials to identify the most cost-effective actions to meet
Develop bicycle and pedestrian access to existing and environmental compliance (86).
future rail and ferry facilities. · ISO-Compliant Environmental Management System --
· Major Investment Studies--MTC has adopted the pol- WSDOT is developing a multimodal environmental
icy of subjecting all major projects in the transportation management system (EMS) that will comply with ISO
improvement plan (TIP) to a major investment study 140001. The EMS is expected to embrace all of
(MIS), including an analysis of the environmental WSDOT's program functions and will be equipped to
impacts of the proposed projects. These studies allow evaluate environmental attributes and impacts of all
the agency to begin addressing environmental consid- transportation modes including the ferry system.
erations at a broader level and at an earlier stage in · The Environmental Work Bench--WSDOT is develop-
planning relative to when project-level NEPA consid- ing a GIS-based tool called the Environmental Work
erations are made. Bench for use by planners and environmental staff. The
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Environmental Work Bench is being used on a limited The key approaches and concepts recommended in the
basis to identify and detect environmental issues early in WisDOT reference manual are described below:
the planning process. This system is being defined as an
early environmental detection program for identifying · Key Concepts
"red flag" environmental concerns at the statewide high- System-level impacts should consider cumulative
way systems level. The analyses performed by this sys- impacts that build upon one another, secondary
tem will also provide important information to regional impacts that occur after the immediate influence of a
transportation planners. MPO officials are expecting to project or program, complementary effects that occur
incorporate this approach into their planning processes, when the impacts of one group of actions reinforce
especially those relating to the environmental assess- the effects of another set of actions, and mitigating
ment of regional plans as required by state law. effects that can be undertaken to offset the effects of
· Performance Measurement Quarterly Reporting-- another set of actions.
Although neither targets nor standards have been estab- Impact assessment at the systems level should
lished for the WSDOT's environmental goals, DOT include a comparative assessment of the following
staff uses a performance measurement quarterly report three factors: type of action category, scale of action,
to assess and publicly report on how well the system is and location.
performing. The types of impacts that potentially should be
reported include direct, indirect, and secondary
impacts.
Wisconsin Department of Transportation Proposed Methods for Identified Impact Categories
Traffic congestion is a direct transportation effect that
The System-Plan Environmental Evaluation (SEE) must be addressed in an SEE. Two approaches are
required by Wisconsin state law and implemented by a state feasible depending on the existence of a statewide
administrative rule is one of the most demanding of such traffic network model.
legal mandates in the United States. As seen in Chapter 3, the 1. Recent traffic volume counts can be adjusted based
rule that has implemented the law was very specific in the on assumed population growth rates to estimate
types of impacts that were to be part of an SEE analysis. future traffic volumes, or extrapolate future vol-
There was little doubt among WisDOT officials about the umes from historical data. Increased traffic conges-
type of information that was necessary for the SEE analysis, tion then can be estimated by identifying congested
but it was not clear what types of tools and what level of facilities where additional volumes would likely
sophistication would be needed to satisfy legal requirements. occur, growth areas that could overwhelm existing
The first step in the SEE approach was to develop a screen- facilities, and induced travel that could shift devel-
ing tool to determine whether an SEE was necessary. For the opment patterns and/or generate additional traffic.
most recent plan evaluated with an SEE, the Wisconsin State 2. A statewide traffic model can be used to predict
Highway Plan, the types of environmental criteria considered future traffic volumes on selected network links,
for each of the system alternatives included: air quality, thus providing such information as changes in vol-
energy consumption, sensitive land and water resources, umes, levels of service, or hours of delay.
indirect land-use impacts, economic development conse- General energy impacts will be influenced by land-
quences, and community and neighborhood impacts. For use patterns, mode shifts, induced travel, and speed/
each of the impact categories, the SEE analysis provided a congestion changes. System plans should be com-
description of the types of mitigation that were likely to be pared with a determination of whether smaller,
implemented for the different projects and impacts being greater, or approximately equal changes of these
considered. In each case, WisDOT experience with each mit- dimensions will occur. If model outputs are available
igation strategy was highlighted. Figure 20 shows the screen- that produce VMT and average speed estimates, these
ing tool used to determine whether an SEE is necessary. outputs can be used with fuel mileage rates to esti-
Because of the mandate to conduct SEEs, WisDOT pre- mate energy consumption.
pared a reference manual that outlined the tools and methods Air quality impacts should be considered in light of
that were appropriate for the level of analysis that was to land-use patterns, mode shifts, induced travel, conges-
occur in systems planning. Unlike other states, WisDOT has tion reduction, and location of travel growth (e.g., in a
a fairly sophisticated statewide modeling capability. Freight nonattainment area). VMT-based analysis would use
flow projections are based on national databases and a pollutant emission factors from air quality models to
statewide model allows WisDOT officials to forecast traffic estimate the total emissions generated based on travel
volumes. In addition, GIS data for agricultural land, endan- volumes, VMT, and travel speeds. In nonattainment
gered resources, and water resources have been an important areas, the regional travel demand model could be used
component of the SEE. to produce estimates of emissions directly.
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Figure 20. Wisconsin's Systems-Plan Environmental Evaluation Screening Tool.
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Figure 20. (Continued). Wisconsin's Systems-Plan Environmental Evaluation Screening Tool.
Source: Cambridge Systematics, Inc., 1994 (87).
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A general assessment of land-use impacts would Direct Land-Use Impacts
include both the direct and indirect effects of trans-
portation improvements. Direct impacts that should · Sensitive land--The types of sensitive land identified
be considered in an SEE include the cumulative effect were agricultural land, habitat fragmentation, and
of acquisition of agricultural land for system needs endangered resources. The effect on agricultural land
and the cumulative effect of land acquisition for other was estimated as the number of acres taken to build
land uses that may not be replaceable. These direct highways. The number of lane-miles added and poten-
impacts would depend on the type of action being tial new bypasses constructed were used as a surrogate
considered, scale of application, and location. Simi- for habitat fragmentation. The effect on endangered
larly, indirect land-use impacts would be influenced resources was measured by using National Heritage
by these characteristics. Inventory data to determine how many sites were within
Economic effects should consider the overall level of one mile of a potential highway improvement. This
investment, the source of funds, the cost of doing analysis showed that the recommended plan could
business such as shipping costs, construction-related affect endangered resources about 700 times compared
employment, and longer-term operating and mainte- to 250 times for the base case.
nance jobs. Once again, the type of facility, scale of · Sensitive water--The two types of water quality impacts
application, and location will influence the eventual reported were construction-related erosion/runoff and
economic effect of plan investment. postconstruction storm water runoff. The measures used
Community impacts will be directly influenced by the for construction-related water issues included the num-
type of investment being considered and the charac- ber of lane-miles added, the number of bridges replaced,
teristics of the neighboring community. The number the number of new bridges constructed, and the number
and significance of the potential impacts for each of wetlands affected. The evaluation showed that the rec-
alternative's elements should be explained in narra- ommended plan would require two-and-one-half times
tive form. With respect to noise impacts, the plan as many lane miles as the base case, the replacement of
alternatives should be ranked in order of their poten- 337 bridges over water, and the construction of 217 new
tial noise impacts. bridges over water (in comparison, the base case would
System plans should be compared based on their over- replace 45 fewer bridges and would construct 76 new
all potential effect on large system scale natural areas bridges). The recommended plan would also convert 900
and ecosystems. This includes both sensitive land to 1,100 acres of wetlands. Postconstruction storm water
areas as well as water resources. At the system plan- runoff was measured with the additional new lane-miles
ning level, in most cases, only general conclusions can variable, thus indicating a two-and-one-half times
be made about potential impacts in this category. impact over the base case.
An evaluation matrix should be used to present the
overall results of the comparative analysis. This
matrix most likely would be in narrative form. Indirect Land-Use Impacts
The impacts considered, and the manner in which they were Indirect land-use impacts reflect the potential of new
analyzed, included traffic congestion, direct and indirect transportation capacity to either induce new development
land-use, economic development, and community and neigh- or alter the existing pattern of development. As noted in the
borhood impacts. report, quantifying this effect, especially at the systems
level, is very difficult. The recommended plan includes
quantitative, comparative statements on potential sec-
Traffic Congestion Impacts ondary land-use impacts by citing miles of new roads by
location and type, and by identifying general impacts that
· Air quality--The latest MOBILE model emission factors may occur. Table 13 shows the qualitative information that
were multiplied by VMT for each alternative to arrive at was presented in the plan to illustrate the different types of
an estimate of total emissions. The analysis showed that land-use impacts that may occur by location and type of
implementation of the recommended plan would result in road investment.
emission levels that were 14% lower than in 2000.
· Energy consumption--Miles per gallon data for 1997
were applied to 2020 annual VMT classified by Economic Development Impacts
various levels of congestion and by functional classi-
fication in both urban and rural areas. Fuel consump- The discussion on economic development impacts was
tion under the recommended plan was slightly less very general, with linkages between improvements to
than the base case. mobility and subsequent enhancement of economic activity
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TABLE 13 Indirect land-use impacts described in Wisconsin State Highway Plan
Source: Wisconsin Department of Transportation, 2000 (88).
highlighted. For example, this section made statements · "The plan's recommended improvements to the Cor-
such as ridors 2020 system would better enable tourists trav-
eling on those routes to experience a more enjoyable
· "Recommended improvements are intended to enhance trip to and from Wisconsin tourism destination points
both mobility between Wisconsin communities and than would improvements recommended in the base
linkages to major destinations in neighboring states." case."
