US Army Corps of Engineers
Baltimore District

Regulatory Sourcebook

Official source for permitting policies, guidelines, regulations and procedures of the Baltimore District Regulatory Branch.  

When designing a project which proposes impacts to aquatic resources, the applicant must explore all possible project alternatives and take all appropriate steps to avoid and minimize the adverse impacts to waters of the United States, including jurisdictional wetlands, to the maximum extent practicable.  Practicable means available and capable of being done after taking into consideration cost, existing technology, and logistics in light of overall project purpose. When preparing a DA permit application, the applicant must demonstrate that he/she has investigated the project alternatives and available options to avoid and minimize impacts to waters of the United States by including information related to the alternatives evaluated and the findings of the alternatives with the DA permit application.  After all available and practicable project alternatives have been investigated, and impacts to waters of the United States are deemed to be unavoidable, compensatory mitigation for the unavoidable impacts will likely be required.  The conditions of the required mitigation will be included in the DA permit as special conditions.

Mitigating the environmental impacts of necessary development actions on the Nation's wetlands and other aquatic resources is a central premise of Federal wetlands programs, and the Clean Water Act (CWA) Section 404 permit program relies on the use of compensatory mitigation to offset unavoidable impacts to aquatic resources. The preferred hierarchy, as stated in the EPA/ Corps Mitigation Rule, for the forms and location of compensatory mitigation is as follows:

1. Mitigation bank credits from an approved mitigation bank,
2. In-lieu fee (ILF) program credits from an approved ILF program,
3. Permittee-responsible mitigation under a watershed approach,
4. Permittee responsible mitigation through on-site and in-kind mitigation, or,
5. Permittee-responsible mitigation through off-site and/or out-of-kind mitigation.

When is Mitigation Required?
The mitigation sequence established by the Clean Water Act Section 404(b)(1) Guidelines has been retained in the Mitigation Rule. Proposed impacts must first be avoided to the maximum extent practicable. Remaining unavoidable impacts must then be minimized. Finally, unavoidable impacts must be compensated for to the extent appropriate and practicable.