NEPA and Transportation Decisionmaking
The Importance of Purpose and Need in Environmental Documents
September 18, 1990
The purpose and need
section is in many ways the most important chapter of an environmental
impact statement (EIS). It establishes why the agency is proposing to
spend large amounts of taxpayers' money while at the same time causing
significant environmental impacts. A clear, well-justified purpose and
need section explains to the public and decisionmakers that the expenditure
of funds is necessary and worthwhile and that the priority the project
is being given relative to other needed highway projects is warranted.
In addition, although significant environmental impacts are expected to
be caused by the project, the purpose and need section should justify
why impacts are acceptable based on the project's importance.
As importantly, the
project purpose and need drives the process for alternatives consideration,
in-depth analysis, and ultimate selection. The Council on Environmental
Quality (CEQ) regulations require that the EIS address the "no-action"
alternative and "rigorously explore and objectively evaluate all
reasonable alternatives." Furthermore, a well-justified purpose and
need is vital to meeting the requirements of Section 4(f) (49 U.S.C. 303)
and the Executive Orders on Wetlands (E.O. 11990) and Floodplains (E.O.
11988) and the Section 404(b)(1) Guidelines. Without a well-defined, well-established
and well-justified purpose and need, it will be difficult to determine
which alternatives are reasonable, prudent and practicable, and it may
be impossible to dismiss the no-build alternative.
planning process, which includes regional, sub-area, and corridor planning,
can serve as the primary source of information for establishing purpose
and need as well as evaluating alternatives. Information and forecasts
of vehicle miles of travel, travel demand, highway and travel speeds,
traffic diversion, time of day characteristics, and traffic accident rates
can be provided by the planning process. This information can be used
to evaluate congestion, air quality, safety, and other environmental issues
for various transportation alternatives including the no-build alternative.
Planning can also estimate the benefits and costs associated with highway
and transit projects that can be used in the development of project "purpose
Consideration of Alternatives
In urbanized areas,
the urban transportation planning process required by Section 134 of Title
23, should result in plans and programs that are consistent with the comprehensively
planned development of an area and that integrate transportation, land
use, and environmental considerations. Comprehensive planning, which includes
transportation, should establish the basic purpose and need for specific
projects and the system wide consequences of operational improvements
and the no-build alternative. For example, the planning process should
identify the need for a transportation improvement between points x and
y at some future date. Further, in a high percentage of cases, a decision
on the appropriate mode (highway or transit) and the basic project concept
(freeway on new location, upgrade of existing facility, light rail transit,
bus/high-occupancy vehicle lanes, approximate travel demand, etc.) can
be determined. In other cases, it may not be possible to resolve these
issues until the conclusion of the project development process. Scoping
meetings early in the environmental process are an excellent means to
reach agreement with the participants on the basic purpose and need for
the project, the consequences of the no-build alternative, and operational
improvements and, where possible, the mode and project concept.
After the basic purpose
and need for the project are established, a number of lines can theoretically
still be drawn to connect points x and y. If the project's purpose and
need are so vague as to only stipulate that a transportation improvement
between x and y is needed, then reasonable alternatives would cover a
wide range and must be evaluated to comply with the CEQ regulations. As
the project's purpose and need is refined, a number of alternatives will
drop out, thereby permitting a more focused analysis of those alternatives
which truly address the problem to be solved. As alternatives are dropped
from consideration, it is recommended that the concurrence of those cooperating
agencies with jurisdiction by law be sought in that decision.
In a similar manner,
the type of improvement to be considered even after the planning process
may be wide ranging: from upgrading an existing facility to multi-lane
freeway on now location. The traffic demands, safety concerns, system
continuity considerations, etc., all will help define reasonable alternatives
and products from the transportation planning process should serve as
a primary source for this information.
Beyond the CEQ regulations
requirement of evaluating all, or a reasonable number representative of
the full spectrum of reasonable alternatives, there are other more action-limiting
requirements for alternatives under Section 4(f), the Executive Orders
on Wetlands and Floodplains, and the Section 404(b)(1) guidelines. To
address these requirements and conclusively demonstrate that some alternatives
are not prudent or practicable, a well-justified purpose and need are
The use of land from
a Section 4(f) protected property (significant publicly owned public park,
recreation area or wildlife and waterfowl refuge, or any significant historic
site) may not be approved unless a determination is made that there is
no feasible and prudent alternative to such use. There are numerous factors
which could render an alternative "not prudent" because of unique
problems, including cost and environmental impacts. If an alternative
does not meet the project's purpose or satisfy the needs then the alternative
is not prudent provided the purpose and need section can substantiate
that unique problems will be caused by not building the project.
If a proposed action
is to be located in a wetland or it entails a floodplain encroachment
with significant impacts, a finding must be made that there is no practicable
alternative to the wetland take or floodplain encroachment. Any alternative
which does not meet the need for the project is not practicable. If the
project's purpose and need are not adequately addressed, specifically
delineated and properly justified, resource agencies, interest groups,
the public or others will be able to generate one or possibly several
alternatives which avoid or limit the impact and "appear" practicable.
Sometimes long, drawn out negotiations or additional analyses are needed
to clearly demonstrate that an alternative is not practicable, where a
well-described justification of the project's purpose and need would have
clearly established it.
If an alternative
does not satisfy the purpose and need for the project, as a rule, it should
not be included in the analysis as an apparent reasonable alternative.
There are times when an alternative that is not reasonable is included
based on the request of another agency or due to public expectation. In
such cases, it should be clearly explained why the alternative is not
reasonable (or prudent or practicable), why it is being analyzed in detail
and that because it is not reasonable that it will not be selected.
Basic Ingredients of Purpose and Need
The purpose and need
should be as comprehensive and specific as possible. For example, rather
than simply stating that additional capacity is needed between two points,
information on the adequacy of current facilities to handle the present
and projected traffic, (e.g., what capacity is needed and the level of
service for the existing and proposed facilities) should be discussed.
Other information on factors such as safety, system linkage, social demands,
economic development, and modal interrelationships, etc., that the proposed
project will attempt to address, should be described as fully as possible.
This will assist in pinpointing and refining the alternatives which should
be analyzed. Further, it will in a sense "protect" those viable
alternatives from sniping by external interests and capricious suggestions
to study something else. If the purpose of and need for the proposed project
are rigorously defined, the number of "solutions" which will
satisfy the conditions can be more readily identified and narrowly limited.
The purpose and need
section of the project may, and probably should, evolve as information
is developed and more is learned about the project and the corridor. For
example, assume that the only known information with regard to purpose
and need is that additional capacity is needed between points x and y.
At the outset, it may appear that commuter traffic to a downtown area
is the problem and only this traffic needs to be served. A wide range
of alternatives may meet this need. As the studies progress, it may be
learned that a shopping center, university, major suburban employer, and
other traffic generators contribute substantially to the problem and require
transportation service. In this case, the need is further refined so that
not only commuter trips but also student, shopping, and other trips will
would clearly reduce and limit the number of alternatives which could
satisfy the project's purpose and need, thereby reducing the number and
range of reasonable, prudent and practicable alternatives. If an alternative
is suggested that does not serve the university or other traffic generator,
and such service is a vital element of the project, the alternative may
be eliminated from future study since it does not meet the need for the
In the example above,
it should be noted that products of the urban transportation planning
process should identify many of the elements which contribute to the transportation
problems. To the extent that the planning process develops these products
and these products are utilized in project development, it may not be
necessary to prepare additional studies.
Some of the elements
which may assist in explaining a project's purpose and need (e.g., capacity,
safety, system linkage, etc.), are described on page 14 of FHWA Technical
Advisory T 6640.8A - "Guidance for Preparing and Processing Environmental
and Section 4(f) Documents." This discussion is included here as
an appendix. All of the elements which are relevant should be as fully
developed as possible and utilize as specific data as possible to compare
the present, future no-build, and future build conditions. Data should
be presented on such factors as reduction in vehicle hours of travel,
improvements in travel speeds on the system, reduction in traffic accidents,
injuries and fatalities, savings in cost to the traveling public, enhanced
economic development potential, increased tax bass, improved access to
public facilities, etc. It is not sufficient to state that the project
is needed to provide increased capacity and improve safety. Supporting
data must be provided.
Purpose and Need in Decisionmaking
As noted above, the
purpose and need define what can be considered reasonable, prudent, and
practicable alternatives. The decisionmaking process should first consider
those alternatives which meet the purpose and need for the project at
an acceptable cost and level of environmental impact relative to the benefits
which will be derived from the project.
At times, it is possible
that no alternative meets all aspects of the project's purpose and need.
In such a case, it must be determined if the alternatives are acceptable
and worthwhile pursuing in light of the cost, environmental impact and
less than optimal transportation solution. To properly assess this, it
is important to determine the elements of the purpose and need which are
critical to the project, as opposed to those which may be desirable or
simply support it, the critical elements are those which if not met, at
least to some minimal level, would lead to a "no-build" decision.
Determining critical needs could include policy decisions as well as technical
Other times, the cost
or level of environmental impact are not acceptable and an alternative
that only partially meets the purpose and need or the no-build alternative
must be considered. If the costs are justified in relation to the transportation
benefits, then a less than full-build alternative may be acceptable.
In the vast majority
of cases, however, at least one alternative will fully meet the purpose
and need at an acceptable cost and level of impact. In cases where more
than one alternative fully meets the purpose and need, a number of factors
including cost, traffic service, safety, public support, environmental
impact, etc., will be considerations in reaching the decision on which
is the preferred alternative. The requirements of Section 4(f), the Wetland
and Floodplain Executive Orders, and the Section 404(b)(1) guidelines,
of course, play an important role in this process.
Key Points to Remember
In summary, the purpose
and need section in the EIS lays out why the proposed action, with its
inherent costs and environmental impacts, is being pursued. If properly
described, it also limits the range of alternatives which may be considered
reasonable, prudent, and practicable in compliance with the CEQ regulations,
Section 4(f) the Executive Orders on Wetlands and Floodplains, and the
Section 404(b)(1) guidelines. Further, it demonstrates the problems that
will result if the project is not implemented.
There are three key
points to remember relative to the purpose and need section of an EIS.
It should be:
- justification of why the improvement must be implemented;
- as comprehensive and specific as possible; and,
- reexamined and updated as appropriate throughout the project development
The following is a list of items which may assist in the explanation of
the need for the proposed action. It is by no means all-inclusive or applicable
in every situation and is intended only as a guide.
- Project Status - Briefly describe the project history including actions
taken to date, other agencies and governmental units Involved, actions
pending, schedules, etc.
- System Linkage - Is the proposed project a "connecting link?"
How does it fit in the transportation system?
- Capacity - Is the capacity of the present facility inadequate for
the present traffic? Projected traffic? What capacity is needed? What
is the level(s) of service for existing and proposed facilities.
- Transportation Demand - Including relationship to any statewide plan
or adopted urban transportation plan together with an explanation of
the project's traffic forecasts that are substantially different from
those estimates from the 23 U.S.C. 134 (Section 134) planning process.
- Legislation - Is there a Federal, State, or local governmental mandate
for the action.
- Social Demands or Economic Development - New employment, schools,
land use plans, recreation, etc,. What projected economic development/land
use changes indicate the need to improve or add to the highway capacity?
- Modal Interrelationships - How will the proposed facility interface
with and serve to complement airports, rail and port facilities, mass
transit services, etc.?
- Safety - Is the proposed project necessary to correct an existing
or potential safety hazard? Is the existing accident rate excessively
high? Why? How will the proposed project improve it?
- Roadway Deficiencies - Is the proposed project necessary to correct
existing roadway deficiencies (e.g., substandard geometrics, load limits
on structures, inadequate cross-section, or high maintenance costs)?
How will the proposed project improve it?
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