When the U.S. Army Corps of Engineers (Corps) reviews a project that requires Department of the Army authorization, our evaluation typically includes a determination of whether the applicant has taken sufficient measures to mitigate the project’s likely adverse impact on the aquatic ecosystem. Mitigation is a three-step sequential process:
Avoid: Take all appropriate and practicable measures to avoid those adverse impacts to the aquatic ecosystem that are not necessary.
Minimize: Take all appropriate and practicable measures to minimize those adverse impacts to the aquatic ecosystem that cannot reasonably be avoided.
Compensate: Implement appropriate and practicable measures to compensate for adverse project impacts to the aquatic ecosystem that cannot reasonably be avoided or further minimized. This step is also referred to as compensatory mitigation.
The Corps and the Environmental Protection Agency (EPA) issued regulations regarding mitigation on April 10, 2008. Compensatory Mitigation for Losses of Aquatic Resources (33 CFR 332), also known as the Mitigation Rule or Final Rule, became effective on June 9, 2008. The Mitigation Rule establishes standards and criteria for compensatory mitigation, including on-site and off-site permittee-responsible mitigation, mitigation banks, and in-lieu fee mitigation to offset losses associated with unavoidable impacts to waters of the United States authorized through the issuance of Department of the Army (DA) permits pursuant to section 404 of the Clean Water Act (33 U.S.C. 1344) and/or sections 9 or 10 of the Rivers and Harbors Act of 1899 (33 U.S.C. 401 et seq.).
The Mitigation Rule states that a permit application must include a statement describing how impacts to waters of the United States (U.S.) are to be avoided and minimized. The application must also include either a statement describing how impacts to waters of the U.S. are to be compensated for or a statement explaining why compensatory mitigation should not be required for the proposed impacts (33 CFR 332.4(b)(1)).
Colorado Mitigation Procedures (COMP)
On June 26, 2020, the Corps issued a public notice approving the Colorado Mitigation Procedures (COMP) v2. The COMP outlines basic regulatory process the Corps will follow to determine compensatory mitigation requirements, including when it may be appropriate to use wetland and/or stream functional and condition assessments (FCAMs), within the State of Colorado.
Colorado Mitigation Procedures (COMP) v2
Colorado Stream Quantification Tool (CSQT)
On September 29, 2020, the Corps issued a public notice approving the use of the Colorado Stream Quantification Tool (CSQT) v1. The CSQT is a stream condition assessment method based on the Stream Functions Pyramid Framework. The CSQT was developed as a result of a multi-agency collaborative effort led by USACE and USEPA to establish an objective, measureable, repeatable method to calculate debits and credits for stream impacts and mitigation in accordance with the 2008 Mitigation Rule (33 CFR 332), South Pacific Division (SPD) Mitigation and Monitoring Guidelines (MMGs), and Colorado Mitigation Procedures (COMP).
The CSQT assigns values to various stream conditions within function-based parameters, and the difference between pre- and post-construction conditions serves as the basis for calculating credits and debits at mitigation and impact sites, respectively.
The CSQT is composed of spreadsheet tools, a user manual, and a scientific support document. Additionally, USACE has developed a review checklist to help ensure that assessments are complete, based on sufficient data, follow the user manual, and reach reasonable conclusions. These documents are provided below in the links below:
CSQT Review Checklist
Additional information about the CSQT can be found on our CSQT page.
Mitigation Ratio-Setting Checklist
The South Pacific Division Regulatory Program Standard Operating Procedure for Determination of Mitigation Ratios outlines the process for determining compensatory mitigation requirements as required for processing of Department of the Army (DA) permits under Section 404 of the Clean Water Act, Section 10 of the Rivers and Harbors Act, and Section 103 of the Marine Protection, Research, and Sanctuaries Act.
Instructions for the SOP for Determination of Mitigation Ratios
MRSC Checklist Examples
Mitigation Plan Requirements for Permits
For individual permits, the permittee must prepare a draft mitigation plan and submit it with the application for review. A final mitigation plan must be submitted to and approved by the USACE before an individual permit can be issued (33 CFR 332.4(c)(i)).
For general permits, if compensatory mitigation is required, the USACE may approve a conceptual or detailed mitigation plan but a final mitigation plan must be approved before the permittee commences work in waters of the United States (33 CFR 332.4(c)(ii)).
Regional Compensatory Mitigation and Monitoring Guidelines
The South Pacific Division has published Regional Compensatory Mitigation and Monitoring Guidelines (Guidelines) to be followed in South Pacific Division’s subordinate districts (Albuquerque, San Francisco, Sacramento, and Los Angeles districts) regarding procedures for compensatory mitigation as required for processing of Department of the Army (DA) permits under Section 404 of the Clean Water Act, Section 10 of the Rivers and Harbors Act, and Section 103 of the Marine Protection, Research, and Sanctuaries Act. The Public Notice, including the Guidelines and Mitigation Monitoring Report Form, can be viewed at the link below:
Uniform Performance Standards
The Uniform Performance Standards include physical, hydrological, and biological metrics for use in determining interim and final mitigation success, as well as adaptive management measures. These performance standards are required as part of any mitigation plan. The USACE Project Manager will work with applicants and their consultants to assist in identifying applicable performance standards for mitigation sites.
To find Mitigation Banking information, click here to access the Regional In-lieu Fee and Banking Information Tracking System (RIBITS).
There are currently no Mitigation Banks in New Mexico or in the Albuquerque District's Area of Responsibility in Texas.
Mitigation Workshop Materials
The Regulatory Division held a workshop on March 12, 2015 on both the Regional Compensatory Mitigation and Monitoring Guidelines and the Mitigation Ratio-Setting Checklist. The presentations may be obtained by clicking on the links below:
Regional Compensatory Mitigation and Monitoring Guidelines Presentation
Mitigation Ratio-Setting Checklist Presentation
Between May 2019 and October 2019, the Corps hosted a number of workshops on the CSQT and the COMP. These presentations are intended to provide examples and offer perspective to aid in understanding the CSQT and its intended use within the 404 permitting program. The presentations do not constitute agency policy or procedures:
Presentation 1 of 4: Colorado Mitigation Procedures (COMP)
Presentation 2 of 4: Colorado Stream Quantification Tool (CSQT)
Presentation 3 of 4: Functional Loss (Debit Example)
Presentation 4 of 4: Functional Lift (Credit Example)