Wetlands mitigation has become increasingly common since the first projects in the early 1980s. However, many agencies are moving away from compensatory wetland mitigation on a case-by-case basis and are instead relying more heavily on mitigation banking. Wetland mitigation banking is the enhancement, restoration, or creation (or in limited instances the preservation) of wetlands prior to the proposed destruction of a wetland. Individuals and companies are able to purchase mitigation credits from the bank instead of having to work through the entire permitting and mitigation process on their own. The advantages of a mitigation bank are that the wetlands are generally larger, they are established prior to the destruction of wetlands which allows them to function like a natural wetland sooner, and by consolidating mitigation effort for multiple projects, it saves time and money by reducing the amount of construction that would otherwise be associated with several smaller projects. Disadvantages of mitigation banks include the increased loss of smaller isolated wetlands and the potential for reduced wetland acreage and function in a particular watershed.

The goal of wetland mitigation banking is to create self-sustaining wetlands that provide ecologic equivalence to the wetland sites that are being impacted. Once sites have been selected, there are many legal, social, and ecological factors that must be considered in establishing and operating a wetland mitigation bank. There are hundreds of wetland mitigation banks established in the U.S., but rules and regulations are still being formulated for many states and there is no specific comprehensive U.S. standard. However, rules may include minimum size restrictions, performance bond measures, and location restrictions. Click here to check out an Environmental Protection Agency fact sheet for more information on mitigation banking.