Wetland Mitigation Cost Calculator

The Wetland Mitigation Cost Calculator compares two ways developers satisfy Clean Water Act Section 404 mitigation requirements after impacting wetlands: buying credits from an approved mitigation bank, or constructing and monitoring replacement wetlands yourself (permittee-responsible mitigation). The federal compensatory-mitigation rule that governs this choice, 33 C.F.R. Part 332 (jointly issued by the U.S. Army Corps of Engineers and EPA), sets a regulatory preference order for the district engineer reviewing a permit — mitigation bank credits first, then in-lieu fee program credits, then permittee-responsible mitigation last — and requires at least a 1:1 acreage or linear-foot replacement ratio, with a higher ratio commonly required to account for factors like the method of mitigation or its likelihood of success. Required Mitigation Acres is Impacted Wetland Acres multiplied by the Mitigation Ratio (commonly 2:1, meaning two replacement acres per acre impacted), and raising either Impacted Wetland Acres or the Mitigation Ratio raises both the required acreage and, downstream, the Bank Credit Cost.

Bank Credit Cost is simply Required Mitigation Acres times Bank Credit Cost per acre -- it's completely unaffected by the permittee-side inputs (Annual Monitoring Cost, Permittee Construction Cost, Monitoring Period), since those only enter the calculation for the permittee-responsible path. Permittee Total Cost, on the other hand, adds Construction Cost to Total Monitoring Cost, and Total Monitoring Cost itself grows with the Monitoring Period -- the longer regulators require you to monitor and report on the replacement wetland's success, the more that ongoing cost compounds, since it's charged per acre per year for the full period. The calculator reports whichever option is cheaper and by how much. What this does not account for: mitigation bank credit availability (banks in your watershed may be sold out), the risk that permittee-responsible sites fail their monitoring performance standards and require additional remediation, or regulatory approval timelines that differ meaningfully between the two paths.