Less than 5% of the US consists of wetlands. However, Hermantown has extensive wetlands within city limits, covering between 30% and 40% of Hermantown. Wetlands are recognized as highly specialized landscapes in need of protection.
Wetlands have several functions, including stream recharge, flood control, groundwater recharge, wildlife habitat, pollutant filtration, aesthetic value, and more.
There are several different types of wetlands found within Hermantown. The majority of wetlands in Hermantown are shrub or wooded swamps. These wetlands usually have standing water in the spring but dry out over the summer when there is less rain. Typical shrubs include willows, red-osier dogwood, and alder. Typical trees include black ash, tamarack white cedar, black spruce, balsam fir, and red maple. Other wetlands in Hermantown include wet sedge meadows, shallow ponds, and moss-covered bogs.
Not all wetlands have cattails. In the spring, any land that retains water for over a two-week period may be a wetland. In the summer, vegetation is a good indicator of wetlands. Plants like sedges, iris, bluejoint, alder, willow, black ash, and selected ferns are usually found in wetlands.
In Hermantown all projects impacting wetlands require a formal wetland delineation. A wetland delineator approved by the city must evaluate the following three principal wetland components:
- Hydrology: soil must be saturated to the surface for at least 5% of the growing season (typically two weeks).
- Soils: must contain unique characteristics indicating the presence of water. In Hermantown, much of the soil contains clay which may retain water. Seasonal wetland soils often have small red iron concentrations, while frequently inundated wetland soil may often be black or gleyed (gray).
- Vegetation: must be dominated by wetland species. All plant species have a wetland rating, indicating their preference or avoidance of wetland habitats.
In order to be defined as a wetland, the area must have all three wetland components. If any component has been altered or is unclear, it is up to the wetland delineator’s professional judgment to determine wetland boundaries. The boundaries should be scientifically defensible and must meet approval of the City of Hermantown, Army Corps of Engineers, and in some instances, the Board of Water and Soil Resources.