What is a Wetland?

When talking about a wetland area, the first thing that comes to mind is water. It's in the name, wet-land, but does that necessarily mean there must be standing water around? The most obvious wetlands are streams, rivers, ponds or lakes, but there are other sites that meet the definition of a wetland without having an obvious source of water flowing through them.

There can be a vernal pool, which is periodically dry, exhibiting little evidence that it differs from the surrounding area. But, that evidence is very important for preserving this economically valuable and delicate area. When dry, the vernal pool looks like a depression with slightly different vegetation growing over it. When wet, however, it becomes a thriving ecosystem for amphibians, insects, birds and even fish. If these vernal pools are lost to development or recreational activities, an entire ecosystem has been destroyed.

Wetlands can also include ephemeral streams. These, similar to vernal pools, are periodically dry. Generally, though, an ephemeral stream or drainage has a defined stream bed, bank and channel, making it a bit more obvious that it conveys water. With this particular body of water, though, when dry, it's easy for a careless or unknowledgeable person to create a barrier to the normal flow of water by filling an area to make a road or crossing.

These are just two examples of wetlands that aren't always wet. Then there are marshes and swamps, generally with surface water or at least a very shallow water table, supporting the wetland vegetation. These are usually very easy to pick out, as most have cattails, reeds and rushes as their dominant plant species. One rule is that if cattails are present, you have a wetland. It's also very important to remember that all wetlands that fall under agency jurisdiction are protected and regulated.

From a legal standpoint, before any filling or work around or near a suspected wetland or riparian (the area around a creek, stream or river) area, the boundaries of the wetland must be determined to avoid impact. This is done with a wetland delineation performed by professionals. The soils, hydrology (water supply) and vegetation must meet certain criteria to deem the area a wetland. Soil pits are dug in the suspected wetland area and further away to determine which is actual wetland and which is upland (the area outside of the wetland). Certain soils called hydric soils are indicators of wetlands, as well as the wetland species of plants. New technology such as GPS (global positioning system) is mostly used these days to located and plot the perimeter of the wetland. Once the determinations have been made, then the necessary permits have to be obtained and mitigation costs paid if any portion of the wetland is to be impacted.

Generally, the permits include the US Army Corps of Engineers 404 Nationwide Permit and, within California, the California Department of Fish and Game Streambed Alteration Agreement Permit. There is also the 401 Water Quality Certificate from the local Regional Water Quality Control Boards, and sometimes additional permits from cities or counties. Even with all of the bureaucracy and trouble, the process is vital for preserving wetlands and therefore, the environment.