Wetlands are areas where water covers the soil, or is present at or near the surface of the soil all year or during most of the year. A wetland is like a sponge that never completely dries up, absorbing water that swells beyond the banks of an adjacent waterbody or collects in lowland areas. When you see a swamp or marsh in our area, are looking at a wetland.
Why we need to protect wetlands
Formerly thought of as useless areas, we now know that wetlands are vital habitats that support our waterways.
Pollution Control. Wetlands act as “nature’s kidneys” by functioning as living filters that retain or remove polluting nutrients and sediments from surface and groundwater.
Nutrient chemicals such as phosphorus and nitrogen are necessary for plant growth, but are also a classic example of the harm done by “too much of a good thing.” Excess nutrients can damage aquatic ecosystems by promoting an undesirable increase in algae and aquatic plant growth. The result is water reminiscent of pea soup, depleted levels of dissolved oxygen (making it difficult for fish to breathe), and weed-choked and rapidly aging lakes (eutrophication).
Sediment Control. As sediment-laden water flows through a wetland area from the surrounding watershed, the sediments are deposited into the wetland. This reduces the formation of silt in lakes, rivers, and streams. Wetland vegetation and flat topography slow the water’s flow and increases the deposition rate of silt and organic matter. Heavy metals and toxic chemicals often attach to the sediment particles found in surface water runoff. Wetlands can trap these human-made pollutants and remove them from the water column. However, when wetlands are overstressed, they lose their ability to filter and the wetland itself can become sources of pollution.
Erosion Control. In their natural state, wetlands function as an inhibitor or barrier to erosion. The root systems of wetland plants stabilize soil at the water’s edge and enhance soil accumulation at the shoreline. Wetland vegetation along shorelines also reduces erosion by damping down wave action and slowing the speed of the water’s current.
Flood Prevention. Wetlands act as a sponge, temporarily storing flood waters and releasing them slowly, preventing flood peaks and protecting downstream property from flood damage. Wetlands and floodplains often form natural floodways that convey flood waters from upland to downstream areas. This wetland function has become increasingly important in urban areas where development has increased the rate and volume of stormwater runoff.
How Communities can protect wetlands
Michigan’s wetlands protection law requires a permit to drain, dredge, fill, construct, or maintain use in a wetland, but it only applies to wetlands that border waterbodies or waterways, or those that are larger than 5 acres. Yet studies have found that smaller, isolated wetlands can provide as many ecological and water quality benefits as larger wetlands. Also, it is difficult for State staff to monitor all the activities that can occur in wetlands throughout Michigan.
Local communities can enact ordinances that protect smaller, isolated wetlands and provide local oversight over development activities that impact wetlands.
Vegetative Buffers. One of the most effective wetland management practices is to establish a vegetative buffer, or “greenbelt,” around the perimeter – a strip of upland that surrounds the wetland and is maintained in a natural vegetative state. On land where the natural vegetation has been removed, establishing the buffer involves planting trees, shrubs, and ground cover. It also requires eliminating the use of fertilizers and pesticides, and only the most selective cutting or removal of vegetation. The buffer vegetation takes up excess nutrients and pollutants, slows overland water flow, prevents erosion, promotes seepage into the soil, and reduces the “flashy” nature of urban runoff.
Septic Systems. Septic systems are a major source of pollutants for wetlands. If the area over the septic drain field is wet or especially green, or if there is a smell of sewage during rainy periods, then the septic system is not operating properly. Seepage from the system may be polluting nearby areas, including a wetland. Septic systems should be pumped and inspected every two to three years, and annually if there is a garbage disposal in use. Property owners should commit to upgrading the system when necessary, and to water conservation practices (e.g. low-flow toilets and shower heads) that can extend the life of the system.
Fertilizers and Pesticides. Reducing or eliminating the use of fertilizers and pesticides is an effective means of reducing wetland pollution. Many property owners use fertilizers when there is no need. If soil testing indicates the need for fertilizer, follow the manufacturer’s instructions carefully and never apply more than is recommended. There are many safe alternatives to both chemical fertilizers and pesticides. Composted kitchen and yard wastes organically enrich soils, insect predators naturally prey on insect pests in the garden, and organic pesticide formulations provide a non-toxic alternative in the home.
What HRWC is doing to protect wetlands
HRWC staff meets with local governments and communities to discuss the importance of preserving wetlands. We also share tools that we created for establishing ordinances that protect wetlands.
To supplement Michigan’s wetlands program, HRWC has developed a model wetlands ordinance that is consistent with the State law. The ordinance provides local governments with a legally sound tool to protect their wetlands and to provide property owners with consistent, predictable treatment throughout the State.
- Protecting Your Community’s Wetlands, HRWC’s wetland ordinance brochure dated September 2006
- Frequently Asked Questions About Wetlands Ordinances , factsheet dated September 2006
- MDEQ Model Wetlands Ordinance, dated March 2003
- Notes Regarding the MDEQ Model Wetlands Ordinance, prepared April 2006
- Legal Cases Related to Wetlands in Michigan, dated March 2002
- Natural Features Setback Ordinance, passed August 1998. HRWC highly recommends that communities enact a natural features setback ordinance along with a wetland ordinance.