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Superseded Guidance

Attachment 1 Guidance on Environmental Restoration and Pollution Abatement

SAFETEA-LU § 6006, 23 U.S.C. § 328
Attachment 1

Attachment 1

"Eligibility for Environmental Restoration and Pollution Abatement" 23 USC § 328


The purpose of this guidance is to discuss the expanded eligibility of Federal-aid funds under the NHS and the Surface Transportation Program (STP) to address environmental restoration and pollution abatement activities (commonly referred to as stormwater treatment systems) by retrofits to existing transportation projects. This eligibility applies to projects undergoing reconstruction, rehabilitation, resurfacing or restoration, and to stand-alone projects carried out to address water pollution or environmental degradation caused wholly or partially by a transportation facility.


The following are definitions for terms used in Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) Section 6006 and this guidance:

Best Management Practices (BMPs) - structural or nonstructural practices, or combination of practices, designed to act as effective, practicable means of minimizing the impacts of stormwater runoff on water quality. These may include: careful application of site design principles; construction techniques to prevent erosion and the discharge of sediments and other pollutants; source controls to keep pollutants out of stormwater; flow control facilities to reduce discharge flow rates; and treatment facilities to reduce pollutants. The term BMP is also used for behavioral practices such as timely cleaning of catch basins. A BMP can even be restraint of a specific behavior such as minimizing the use of fertilizers, certain pesticides, or road salt and sand.

Environmental restoration - a process involving returning the habitat, ecosystem, or landscape to a productive condition that supports natural ecological functions.

National Pollutant Discharge Elimination System (NPDES)- The NPDES permit program controls water pollution by regulating point sources that discharge pollutants into waters of the United States. This national program addresses non-agricultural sources of stormwater discharges. Many highway stormwater discharges are considered point sources and require coverage under the NPDES permit. The primary method to control stormwater discharges is through the use of best management practices or procedures for controlling stormwater quality.

Pollution abatement project - practices or control measures designed to retrofit existing facilities or minimize stormwater quality impacts from highway projects.

Reconstruction - Examples of activities eligible under the term "reconstruction" include adding new lanes to increase capacity, acquisition of access control coupled with construction of interchanges, or replacement of the full pavement structure.

Resurfacing, restoration, and rehabilitation - work includes placement of additional surface material and/or other work necessary to return an existing roadway, including shoulders, bridges, the roadside, and appurtenances to a condition of structural or functional adequacy.23 CFR§625.2(2)(b).

Retrofit - to fit or construct something new to improve a system or feature that was not available or constructed with an existing project.

Stand alone project - A stand alone project is one that is developed solely for environmental restoration or pollution abatement to minimize or mitigate the impacts caused in whole or in part by a project funded under Title 23. It is not associated with an ongoing transportation construction project.

STIP - State Transportation Improvement Program - The STIP is a multi-year capital improvement program of transportation projects on and off the State Highway System, funded with revenues from the State Highway Account and other funding sources.

TIP - Transportation Improvement Program - The TIP is a multi-year capital improvement program of transportation projects from the MPO.

Watershed - An area or boundary of a region that drains to a river, a waterbody or other drainage system.


1. How does SAFETEA-LU change the eligibility of environmental restoration and pollution abatement activities for Federal-aid reimbursement?

23 U.S.C. § 328 modified the eligibility of Federal-aid funds available under the NHS and the STP to participate in environmental restoration and pollution abatement (stormwater runoff) activities to minimize or mitigate the impacts of any transportation project funded under Title 23. This section primarily deals with the impacts of transportation facilities that were built prior to the current, more stringent requirements for abatement of stormwater runoff. These transportation facilities may have been constructed with limited or no stormwater treatment controls. The SAFETEA-LU provides the means to fund retrofits and the construction of stormwater treatment systems to address water pollution and environmental degradation that is caused in whole or in part by a transportation facility. These measures may be implemented under two basic scenarios.

A. A stand-alone project, one that is developed solely to address stormwater concerns and is not associated with a transportation project that is being developed or is under construction; or

B. In conjunction with a project that is currently being developed for the reconstruction, rehabilitation, resurfacing, or restoration of a transportation facility. In this case, the costs for environmental restoration and pollution abatement may not exceed 20 percent of the total cost of the project.

2. How are retrofits and other pollution abatement measures referred to in SAFETEA-LU distinguished from stormwater abatement measures or BMPs that have become a part of current project design standards and are required to meet NPDES and other permit requirements on Federal-aid projects?

For most projects that involve reconstruction, rehabilitation, resurfacing, and restoration; the construction project will be extensive enough to require the implementation of stormwater BMPs as a part of the project design, to meet current NPDES Phase II or other water quality requirements. These costs would continue to be fully eligible for Federal-aid participation. The 20 percent limitation in 23 U.S.C. § 328, would apply in a case where the transportation project improvements being planned are not extensive enough to require the retrofit of a stormwater feature, but the project sponsor determines that there is an opportunity to provide a retrofit to address water pollution or environmental degradation. An example may be the case of a straightforward resurfacing project in an area where the highway runoff is contributing to water quality problems. It is unlikely that the resurfacing project alone would require any type of permanent stormwater treatment. Federal-aid participation in the cosfsts of any retrofits to address stormwater that are incorporated into this resurfacing project would be limited to 20 percent of the total cost of this repaving project. If costs exceed 20 percent, State or local funds, or donations (see question 8 below) may be used to decrease the cost of the necessary retrofits to a level that is less than 20 percent of the total cost of the project.

3. When would a stand-alone project be considered or identified as necessary?

As part of meeting the EPA's NPDES Phase II requirements for stormwater under the Clean Water Act, State and local governments must meet certain standards or requirements with regard to stormwater runoff. In order to meet these standards, many localities are mapping their stormwater outfalls and analyzing sources of stormwater pollution. A stand-alone project would likely be considered in a situation when an existing highway is identified as contributing to a water quality issue in a watershed, and there is no highway project currently under development or planned in the foreseeable future in the area. In these cases, if one of the sources of pollution is a transportation facility eligible for funding under Title 23, SAFETEA-LU provides that activities such as retrofitting and construction of stormwater treatment systems to meet State and local requirements may be carried out with both NHS and STP funds.

4. What are the planning and environmental review limitations on stand-alone projects?

As with all projects that receive Federal-aid funding, stand-alone projects must be consistent with State and MPO transportation plans and must be included in a fiscally constrained TIP. Development and construction of any project funded under Title 23 would need to meet the requirements of the National Environmental Policy Act, as well as other environmental laws including Federal and State requirements under sections 401 and 402 of the Federal Water Pollution Control Act.

5. Can a stand-alone project be developed to address environmental restoration and pollution abatement control for all sources, even though transportation's portion is minimal?

Many transportation facilities are located in areas that are experiencing growth from development. The overall development may have a contribution to environmental degradation which is far greater than that of the transportation facility. As discussed in number 4 above, stand-alone projects are subject to the same planning requirements as all other Federal-aid projects. In developing a stand alone project for inclusion in the STIP or TIP, fiscal constraint requirements and wise stewardship of Federal-aid dollars would be strong reasons for MPOs and State DOTs to seek partnerships with municipalities, developers and others to co-fund the costs of improving the water quality in the area. This would be particularly true in a situation where the documented contribution of the transportation facility to the environmental degradation is minor in comparison to the contributions from other sources. The following items should be considered when deciding if a stand alone project should be added to a transportation plan or program: overall mitigation needs identified in the watershed and/or stormwater management plans, commitments by the community and landowners to invest in improvements, the scope of the stand alone project, the highway's impact or contribution to the stormwater runoff problem, and whether the proposed mitigation is a reasonable expenditure considering those impacts. Decisions on Federal-aid funding eligibility are made at the FHWA division offices. In addition to meeting other Title 23 and environmental requirements, to be eligible for Federal-aid transportation funds, projects must be consistent with the Statewide Transportation Plan and be included in applicable fiscally constrained MPO Transportation Plans and STIP/TIPs.

6. What other funding is available to pay for stand-alone stormwater retrofit projects?

An additional funding option for stand-alone projects is the environmental enhancement and pollution abatement category under the Transportation Enhancements Program, which is part of the Surface Transportation Program. There are 12 defined categories, one being the mitigation of highway runoff. State transportation agencies have most of the program responsibility for Transportation Enhancement and the process for solicitation and selection is competitive among the 12 categories.

7. What activities are included under environmental restoration?

This guidance supports and recognizes previous FHWA guidance on wetland and natural habitat mitigation. A listing of FHWA wetland mitigation guidance is located at: restoration is a process involving returning the habitat, ecosystem, or landscape to a productive condition that supports natural ecological functions. Since these natural systems are diverse and dynamic, the process of recreating or duplicating their natural, or pre-settlement state is virtually impossible, but the goal of the restoration should be to re-establish the basic structure and function associated with natural, productive conditions. Wetlands are part of the hydrological cycle and are associated with the environmental restoration process. We have existing guidance that deals with wetland and natural habitat restoration and mitigation measures, such as wetland and habitat banks or statewide and regional conservation measures.

Examples of projects that would be eligible for funding include:

8. Can donations of materials and professional services be accepted to reduce the cost of environmental restoration and pollution abatement retrofits?

When consistent with Federal regulation, in-kind services such as: donation of materials or professional services from public or private sources, or donation of right-of-way by a private organization or individuals for environmental restoration and pollution abatement can be utilized. The value of these donated services would reduce the cost of the retrofits and it may be important to consider these options if the retrofit cost without the donations is at or above the 20 percent maximum expenditure limit in SAFETEA-LU.

9. Would DOTs be responsible for addressing combined sewer overflows (CSOs) issues as a retrofit stormwater mitigation effort, if a highway adds stormwater to such a system?

CSOs are usually found in older communities. In the past, communities typically built sewer systems to carry and collect both sanitary and stormwater runoff in the same pipes. This system would carry the wastewater directly to the sewage treatment plant. However, during wet weather events, the volume in the system would typically exceed the capacity of the sewer system and/or the capacity of the sewage treatment plant. The system was usually designed to overflow occasionally and any excess discharges would flow directly into nearby streams, rivers, lakes or estuaries. As time went on, there was a realization that such overflows can be a major source of water pollution in communities served by these systems. CSOs contain not only stormwater, but also untreated human and industrial waste, toxic materials, and debris.

Under EPA's CSO Policy, communities with combined sewer systems are expected to develop long-term CSO control plans that will ultimately provide for full compliance with the Clean Water Act, including attainment of water quality standards. These control plans along with NPDES requirements are developed through the water quality agencies. A DOT's responsibility could include verifying that their system doesn't contain any combined flows (dry weather flows), and that stormwater treatment is such that they are not making the situation worse. In other words, they would need to provide enough stormwater treatment with detention or storage for their project along with pollution prevention measures to keep flows at or below existing levels. Any work would need to be coordinated with their long term CSO control plan and their permitting authority. The cost of treatment or retrofit work to construct stormwater treatment facilities to treat previously untreated highway runoff in compliance with a CSO control plan would be an eligible expense under this guidance. Normally, such projects would be for treatment of highway runoff before it enters the CSO.


Updated: 8/5/2015
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