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Regulatory image of wetlandsMitigation is an important part of the U.S. Army Corps of Engineers’ permitting process. It includes avoiding, minimizing and compensating for impacts to aquatic resources.


If your project cannot avoid or sufficiently minimize affects to wetlands or other waters of the United States, you must compensate for the impacts. This is called compensatory mitigation and is the restoration, establishment, enhancement or preservation of aquatic resources to offset unavoidable losses due to project impacts.


The mitigation rule

Mitigation requirements are outlined in Compensatory Mitigation for Losses of Aquatic Resources Final Rule (33 CFR Part 332), commonly referred to as the “mitigation rule.” The mitigation rule promotes consistency and predictability and improves ecological success of mitigation efforts through better site selection, use of a watershed approach for planning and project design, and use of ecological success criteria to evaluate and measure performance of mitigation projects.

Providing compensatory mitigation

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Mitigation Banks, In-Lieu Fee Programs and Permittee-Responsible Mitigation. Mitigation banks and in-lieu fee programs are generally the preferred options for mitigation because they consolidate resources and involve more financial planning and scientific expertise. These factors help reduce the risk of failure of mitigation projects. The following are acceptable mitigation options, listed in order of environmental preference as described in the mitigation rule:
A mitigation bank is one or more sites where aquatic resources such as wetlands or streams are restored, established, enhanced and/or preserved for the purpose of providing compensatory mitigation in advance of authorized impacts to similar resources. A bank sells mitigation “credits” to permittees. The obligation to provide mitigation is then transferred to the bank sponsor. The bank sponsor is then responsible for implementing the mitigation, monitoring its performance and long-term site management.
An in-lieu fee program involves the restoration, establishment, enhancement and/or preservation of aquatic resources through funds typically paid to state governments, local governments, or non-profit natural resources management organizations. As with banks, credits are sold to permittees by the in-lieu fee sponsor. The in-lieu fee sponsor is then responsible for implementing the mitigation, monitoring its performance and managing the site long-term.
Individual mitigation projects constructed by permittees can also compensate for environmental impacts authorized by the Corps. This option makes the permittee responsible for implementing the mitigation, monitoring its performance and long-term site management. Mitigation projects may occur on the same site as the permitted project or at an offsite location usually within the same watershed. In some cases, permittee-responsible mitigation is the only option. This is typical when proposed impacts are not located within the service area of an approved mitigation bank or in-lieu fee program, or if these mitigation options would not provide appropriate mitigation for the proposed impacts.

What to include in a mitigation plan

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If you’re using a bank or in-lieu fee program you do not need to provide all of the components listed below. However, you should include a description of the baseline conditions at the impact site, the number and type of resource credits to be secured and how these were determined. If compensatory mitigation is required, you must submit a mitigation plan. There are 13 required components in every mitigation plan.
1) Preparation and approval (This component is guidance specific and is not included as an actual component of a compensatory wetland mitigation plan.)
2) Objectives
3) Site selection
4) Site protection instrument
5) Baseline information
6) Determination of credits
7) Mitigation work plan
8) Maintenance plan
9) Performance standards
10) Monitoring requirements
11) Long-term management plan
12) Adaptive management plan
13) Financial assurances
14) Other relevant information
Although not required, assistance from a qualified environmental consultant may be beneficial in developing a comprehensive and acceptable mitigation plan. All mitigation plans require Corps approval.