World Wetlands Day: The Critical Role of Wetlands
by Amy L. Noel, PWS
February 2nd was World Wetlands Day, a day to acknowledge the importance of wetlands in their role as nature’s own water filters and storage facilities. Wetlands clean our water through specialized plant communities and soils rich in organic matter and microorganisms. Their position in the landscape provides a critical “stopping point” for water on its way to our lakes, rivers, and streams.
Metric staff in the Natural Resources Department provide wetland delineation services for a variety of transportation and development projects. These natural resources are often found in areas where development is planned. A wetland delineation is one of the first environmental reviews completed on projects to determine what impacts may occur that are regulated under Section 401 and 404 Clean Water Act. Our wetland scientists determine what areas are true wetlands based on vegetation, hydric soil, and hydrological indicators. In this photo, our scientists are sampling the soils of a suspected wetland area to determine if it has indicators of hydric soil.
Hydric soils are defined as soils that are inundated or saturated for a long enough period to support hydrophytic, or “water-loving”, plants. Soils can be examined for the presence of organic matter and iron deposits that are left behind when the soil is saturated or inundated for a long enough period to develop anaerobic, or low oxygen, conditions. So even if we conduct a site visit during a drier part of the year, there are still clues left in the soil to help us determine if it was inundated or saturated for a long enough period to support wetland vegetation.
In addition to soils, the presence of hydrophytic plants, or plants adapted to survive in wet conditions, are recorded to determine if there is enough presence to call an area a wetland. Plants are given a wetland indicator status that helps scientists determine their affinity to living in wet conditions.
The final indicator that is examined is the presence of wetland hydrology. Sometimes, hydrology is obvious, such as the presence of standing water or saturated soil. However, hydrology indicators are not always so obvious, and scientists need to look for evidence that hydrology was present at a different time during the growing season. Some of the things we look for are the presence of water marks on trees, water-stained leaves, and soil surface cracks.
It is important to note that even if an area doesn’t have standing water present or visibly saturated soils, that does not mean it is not a wetland. Wetlands can be present in areas that can be unexpected as water flow is changed and redirected for development. It’s important to have a wetland scientist who is trained in the identification of wetlands look at your site before proceeding with development.
Next time you have some time, take a visit to Eagle Creek Park in Indianapolis where there are some great wetland areas that support a wide variety of plant and animal species. Keep in mind that wetlands are one of our most important natural resources, and it’s important that we maintain and protect them as they do their job of storing and cleaning our water as well as providing habitat for many plant and animal species.
Happy World Wetlands Day!
