Compensatory mitigation means restoration, enhancement, creation, and under exceptional circumstances, preservation, of wetlands, wetland buffer areas, and other natural habitats, carried out to replace or compensate for the loss of wetlands or natural habitat area or functional capacity resulting from Federal-aid projects funded pursuant to provisions of title 23, U.S. Code. Compensatory mitigation usually occurs in advance of or concurrent with the impacts to be mitigated, but may occur after such impacts in special circumstances.
23 CFR § 777.2
In addition to those contained in 23 U.S.C. 101, the following definitions shall apply as used in this part: