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Mitigating Ecological Impacts Tidbits

These TIDBITS are an assortment of various FHWA guidelines which are consistent with the NEPA, requirements of the Endangered Species Act - ESA and Clean Water Act - CWA, and FHWA policy on mitigation established in 23 CFR 771.105. Environmental Impact policy, 23 CFR 771.105 (d), states that, Measures to mitigate adverse impact [will] be incorporated into the action (a Federal-aid highway project). Mitigation includes avoiding impacts, minimizing impacts, and (where impacts are unavoidable) compensating for impacts. The TIDBITS are intended to give the reader a summary of the basic FHWA requirements to help recognize the various FHWA funding criteria and categories as well as the environmental needs in pursuing and/or establishing mitigation for ecological impacts


Direct Physical modification of an existing feature/condition.

Indirect/Secondary Impacts that are caused by an action and are later in time or farther removed in distance but are still reasonably foreseeable (40 CFR 1508.8). Generally, these impacts are induced by the initial action.

Cumulative Impacts which result from the incremental consequences of an action when added to other past and reasonably foreseeable future-actions (40 CFR 1508.7). These impacts are less defined than secondary effects. NOTE: To be recognized in the applicable NEPA documentation but not required to be mitigated.

Cumulative   Secondary Impacts http://environment.fhwa.dot.gov/guidebook/chapters/v2ch6.htm


Eligibility of ISTEA Funds to Mitigate Historic Impacts to Wetlands


Memorandum of Understanding to Foster the Ecosystem Approach




The Ecosystem Approach and Transportation Development, (October 30, 1995)

Use of Private Wetland Mitigation Banks


Participation in Funding for Ecological Mitigation


Use of Private Wetland Mitigation Banks as Compensatory Mitigation for Highway Project Impacts


Federal Interagency Memorandum of Understanding (MOU) for Implementation of the Endangered Species Act (ESA)


Funding for Establishment of Wetland and Mitigation Banks


Memorandum of Agreement (MOA) on Wetland Delineation


Wetland Delineation and Mitigation



Critter Crossings - https://www.fhwa.dot.gov/environment/wildlifecrossings/

Roadside Vegetation Management - https://www.fhwa.dot.gov/environment/vegmgt/

Easy Ways to Help Wildlife Along Roads - https://www.fhwa.dot.gov/environment/wildlifeprotection/

Page last modified on January 31, 2017
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000