What to know before you work
Minnesota’s landscape includes roughly 10.6 million acres of wetlands. While many people think of wetlands as swampy, marshy areas with standing water and cattails, the reality is wetlands take on many forms. In addition to swampy, marshy areas, wetlands can vary from grassy meadows, to forested wetlands covered in trees and shrubs, to wet areas of cultivated farm fields. Many wetlands are actually dry for most of the year, with no standing water.
Why Wetlands Matter
Before European settlement, studies estimate Minnesota had over 20 million acres of wetland. Today that number has been cut in half. Wetlands are important ecosystems. They hold water, providing for natural water quality improvements by filtering nutrients and sediment that might otherwise pollute and clog waterways. They provide flood protection and shoreline erosion control. Wetlands are also home to many species of fish and wildlife.
Most wetlands in Minnesota are protected by State and/or Federal law. Minnesota’s primary wetland protection law is the Wetland Conservation Act. The law is implemented by local governments, the Minnesota Board of Water and Soil Resources provides assistance and oversight, and the Department of Natural Resources provides enforcement.
- The State law applies to all wetlands, including those on private property, to achieve “no net loss” of wetlands.
- In general, wetland protection laws regulate activities in or near wetlands that can negatively affect the wetland through draining, filling, or excavating.
- There are some exemptions contained within State law for certain activities.
What You Should Know
It can be very difficult to identify wetlands and wetland regulations can be quite complex. Some examples of projects that could potentially affect wetlands include:
- Filling a low area of a residential lot for a building or lawn
- Tiling wet areas of cultivated fields
- Digging a pond in a low area
- Cleaning out an old ditch or improving an existing ditch
- Adding fill for a crossing of a stream or wet swale
If there is the potential for your project to impact a wetland, before you start it is important to contact your local WCA regulatory authority to:
- Find out if the land you intend to alter is a wetland. Remember, an area can be a wetland even if it does not appear wet on the surface.
- Determine if the proposed activity has impacts to a wetland area.
- Assure that any impact to wetlands can be avoided if possible, and properly replaced if not.
Seasonally Flooded Basin or Flat – Type 1 has “seasonal” wetness, but usually is well-drained during much of the growing season. The vegetation here can vary based on the season and duration of flooding, but can range from bottomland hardwoods to herbaceous plants. These types are commonly found in upland depressions and floodplain forests.
Wet Meadows – Type 2 are saturated during the majority of the growing season, have very little visual water, but soil is waterlogged. You will find grasses, sedges, rushes and an assortment of broad-leaved plants. These wetlands are sneaky, filling in shallow basins or farmland sags, also they can border shallow marshes.
Shallow Marshes – Type 3 are waterlogged during the early stages of the growing season and covered with 6 plus inches of water. You will find grasses, bulrush, spikerush and other marsh plants (cattails, arrowhead, pickerelweed). Shallow marshes may form by filling in basins or sloughs, or may border deep marshes on the landward side.
Deep Marshes – Type 4 are formed along the edges of lakes and streams. You will find grasses, sedges, rushes, cattails, reeds and wild rice. Open areas may have waterlily, pondweed, or coontail. These marsh plants can act to slow down water, sometimes allowing for nutrient enriched sediment to be deposited, or by acting as a filter for excess nutrients. There is standing water of 6 inches to 3 feet during the growing season.
Shallow Open Water Wetlands – Type 5 includes shallow ponds and reservoirs that are less than 10 feet deep. You will find pondweed, naiad, coontail, watermilfoil, duckweed, waterlily and spatterdock.
Shrub Swamps – Type 6 have peaty soils and are dominated by shrubs. Shrub swamps receive water from both surface and groundwater sources and occur along slow-moving streams, drainage depressions and floodplains. You will find alder, willow, buttonbrush and dogwood.
Bogs – Type 8 exclusively receive water from rainfall. It is distinguished by wet, spongy, peaty soils. You will find woody, herbaceous, or both, easily identifiable by a squishy covering of moss.