Wetlands have physical, ecological, and legal definitions. The term describes those places in the landscape where water naturally collects or emerges on the surface. Legal definitions depend on the presence of water, the seasonal depletion of oxygen in soils, and the presence of biota adapted to those conditions.
Our wet climate, undulating glacial plateau with its compacted till soils, and broad floodplains, large historical population of beaver resulted in a landscape with vast wetlands, providing summer stream flow for salmon and migrating waterfowl along the pacific flyway.
Wetlands are a large complex topic with a vast literature that hasn't been well developed on this wiki.
Legal Authorities and Jurisdications
- Wetlands are regulated by both federal and state laws. Not all wetlands fall under federal jurisdiction.
- Wetlands under federal jurisdiction are regulated by US Army Corps of Engineers under Section 404 of the Clean Water Act. These codes, rules and regulations concern "waters and wetlands of the United States" which are a subset of all wetlands. The definition of "wetlands and waters" is hotly contested.
- The Washington State Department of Ecology regulates wetlands under the Water Pollution Control Act and the Shoreline Management Act. State decisions are tested for impacts to wetlands under the State Environmental Policy Act. Furthermore, Ecology provides technical assistance to local jurisdictions under the Growth Management Act which requires local Critical Areas Regulation, including wetlands.
- State guidance includes a state manual for wetland determination and delineation, and the washington state wetland rating system
- In addition, wetland mitigation is among the most developed ecosystem service currencies as developers frequently damage wetland function are area to maximize development potential of a site, and then seek to offset those damages through buying into wetland restoration.
- Large areas of wetlands were destroyed during colonization, typically for agriculture. In our dry summer climate and glacial soils, wetlands provide moist organic soils that are extremely productive, and require less irrigation. Agriculture has secured many exemptions from environmental regulation. One of these is a partial exemption of "prior converted wetlands from some kinds of regulation. Generally speaking, you can continue to farm "prior converted wetlands" but cannot undertake development that would prevent reestablishment of wetlands at the cessation of farming.
- In this way, a particular action in a particular wetland may fall under three different jurisdictions, local, state, or federal. An initial component of wetland regulation is "jurisdictional determination" where agencies weigh in about whether they have the authority to regulate. In many cases, land owners avoid the issue by not asking.