GAO urges Corps to clarify non-mitigation determinations for water projects

The Government Accountability Office report finds the U.S. Army Corps of Engineers did not clearly document its determinations that mitigation was unnecessary for 52 of the 74 civil works projects submitted to Congress for authorization during calendar years 2020-2025. GAO recommends the Assistant Secretary of the Army for Civil Works require the Chief of Engineers and the Commanding General to develop guidance for documenting and justifying those non-mitigation determinations in congressional reports.

For the 22 projects where the Corps determined mitigation was needed, GAO observed that the mitigation plans generally incorporated components of the 2008 Rule, "Compensatory Mitigation for Losses of Aquatic Resources." In contrast, the reports accompanying the 52 projects that were deemed not to need mitigation, as well as supporting feasibility reports, lacked a clear, summary format explaining the basis for those determinations.

Corps officials acknowledged that documentation of non-mitigation decisions has not been consistently presented in a concise format and agreed that improved documentation could benefit both Congress and the public. The Assistant Secretary of the Army for Civil Works, however, did not concur with GAO's recommendation, stating that the existing reports contain sufficient technical information.

GAO maintains that the recommendation remains warranted and urges the Corps to issue the proposed guidance so that future authorization reports reliably convey why certain civil works projects will not entail environmental mitigation. The recommendation is pending a formal agency response, which GAO will track and update as it becomes available.