Wetlands are part of the foundation of our nation's water resources and are vital to the health of waterways and communities that surround them. There are eight different types of wetlands in the state of Minnesota. In Rochester, you can find six of these wetland types: shallow marshes, shallow open water, shrub swamps, wooded swamps, seasonal basins, and wet meadows. (The two you will not find in Rochester are bogs and deep marshes.) There are approximately 800 acres* of wetlands within Rochester city-limits, which equates to 2-3% of the ground cover. *This number is dependent upon the season.
The Minnesota Department of Natural Resources (DNR) estimates there are about 10.62 million acres of wetlands remaining in Minnesota. Unfortunately this number is about half of what was originally found in the state. Even with the drastic decrease in the number of wetlands, the state of Minnesota is second only to Florida (among the contiguous states) in the diversity and extent of wetlands.
In this section:
Importance of Wetlands
A wetland is described as an area with mostly wet soils, water either above or just beneath the surface of the ground, and vegetation that is adapted to grow in wet conditions. Wetlands are very important for multiple reasons:
- Erosion Control
Wetlands reduce erosion along lakes and stream banks by reducing the forces associated with moving water.
- Flood Control
Wetlands slow runoff water down and store water intense rain storms and times of snow melt. This then helps to minimize the frequency in which streams and rivers reach catastrophic flood levels.
Wildlife of all shapes and sizes depend on wetlands for food sources, resting spots, protection from predators, and spawning or rearing their young. 43% of threatened or endangered species, including plants and animals, live in or depend upon wetlands.
- Groundwater Support
By detaining surface waters that would otherwise quickly flow away, water in wetlands can instead percolate into the ground. Some wetlands receive groundwater during dry period which then helps reduce the impact of short term droughts.
- Natural Filter
When water is trapped and held in a wetland, nutrients and pollutants become stored in the soils which results in cleaner water flowing into the body of water beyond or below the wetland. Vegetation, like cattails, can absorb some of the pollutants that remain in the soil. Wetlands also moderate water flows, providing time for sediments to settle out before water is released, resulting in cleaner waters.
Wetlands provide opportunities for outdoor recreational pursuits including canoeing, fishing, hunting, birding and exploration.
Wetlands provide economic commodities such as cranberries, wild rice, and fish. Additionally, developments benefit from the spatial amenities wetlands can provide.
Calcareous fens are one of the rarest natural communities in the United States. These unique wetlands, which are a type of wet meadow, are fed by mineral-rich groundwater and have little inflow of surface runoff. Fens are highly diverse with over 100 different plant species, some of which are rare, threatened or endangered.
Fen Fun Facts:
- Fens comprise only 0.03% of all wetlands in Minnesota, making them a very rare type of wetland.
- Of Minnesota's 53,775,155 total acres, fens cover only 4,000 acres - this is equal to 0.007%!
- Biodiversity is high in fens. Almost 20% of the plant species found throughout Olmsted County are found in our fens.
- Fens are home to rare, threatened, and endangered amphibians, reptiles, snails, and butterflies.
- Olmsted County has the third highest number of inventoried fens in the state. 10 of the state's 200 fens are found here.
- There are 4 known fens located with the city limits of Rochester.
Learn more about fens in the handouts below:
- Calcareous Fens: Are you a fen-friendly neighbor?
- Fen-Friendly Care Practices for Stonehedge Residents
- Fen-Friendly Care Practices for Barony Woods Residents
Constructed wetlands, including floating wetlands, are designed to mimic natural bogs and can help clean nutrient-polluted water. Native plants and microorganisms grow through the recycled plastic matrix and act as a natural filtration system for the lake. The wetland also creates habitat above and below the surface of the water, providing a haven for fish, turtles, insects and birds.
You can see floating wetlands in Silver Lake, the Quarry Hill pond, and in a handful of stormwater ponds across Rochester. These floating wetlands have a base made of recycled plastic that is then covered in soil and wrapped in burlap. Native plants are placed into soil-filled cavities and fencing is installed to prevent geese and muskrats from damaging the plants.
- Environmental Protection Agency: Wetlands - Where Water Meets Land
- Minnesota Department of Natural Resources: Wetlands
- Minnesota Pollution Control Agency: Wetlands in Minnesota