|Acres impacted||Acres mitigated||Acres gained (net)||Mitigation ratio|
NOTES: These data cover wetlands acreage affected by Federal-Aid Highway projects, approximately 24% of the total mileage of U.S. public roads. These data are collected by states using varying collection methodologies. The mitigation ratio equals acres mitigated to acres impacted.
SOURCES: 20002004: U.S. Department of Transportation (USDOT), Federal Highway Administration (FHWA), Federal Highway Administration Wetland Mitigation Performance Measure for Federal-Aid Highway Projects Fiscal Year 2004; 20052007: USDOT, FHWA, personal communication, as of August 2007 and September 2009.