World Wetlands Day

February 2 is recognized as World Wetlands Day. What exactly is a wetland, though? In short, a wetland is an area of land that is either covered by water or saturated with water for a portion of the year. Here in Southeast Michigan, wetlands are found both inland and along the Great Lakes coastline from Lake Huron to Lake Erie. Southeast Michigan possesses a variety of wetland types, including emergent, scrub-shrub, and forested wetlands. To learn more about wetlands in the region, visit EGLE’s Wetlands Map Viewer.

Wetlands serve a plethora of ecosystem services, benefits to humans provided by the natural environment and healthy ecosystems. For wetlands, these services include:

• Absorbing excess water during heavy rains,
• Limiting the effects of flooding,
• Protecting coastal areas from storm surges that can wash away fragile beaches and coastal communities, and
• Providing us with economic and community benefits.

Michigan’s coastal and inland wetlands produce more wildlife and plants than any other habitat type in the state. Our Great Lakes Coastal Wetlands are especially critical, as these wetlands are the most productive global natural systems. However, Southeast Michigan has lost 77% of its wetlands. This is largely due to the dredging of wetlands that was common until the 1970s. Since then wetlands are recognized for their ecosystem services. Nevertheless, threats to wetlands persist today. Southeast Michigan’s wetlands are affected by the Great Lakes’ water levels, development of shoreline areas, urban growth, industrialization, and agriculture.

Over the years, the Michigan Department of Environment, Great Lakes, and Energy (EGLE), Ducks Unlimited, Inc. (DU), and SEMCOG have been working together to produce an updated National Wetland Inventory (NWI) dataset. The goal of this inventory is to provide the region with a better picture of the state of wetlands and allow us to obtain critical and updated information for various SEMCOG projects, including our Environmental Sensitivity Project.

Wetlands in the NWI dataset are classified in accordance with the HGM Classification system. The HGM classification system groups wetlands based on geomorphic position and hydrologic characteristics, such as water source and hydrodynamics. In addition to HGM Classifications, we were able to take things a step further and evaluate wetlands on a watershed scale using Landscape Position, Landform, Water Flow Path, and Waterbody Type, also known as LLWW Classification. This enables the categorization of wetlands based on geographic characteristics. This level of wetland assessment is typically used to support watershed planning, zoning decisions, and define restoration priorities at the local or regional level.

These two classification systems allow us to better understand and define wetland functions and values. Within the dataset, you will see fields that include whether a wetland is likely to perform a function.

Water Quality Functions:

• Flood Water Storage
• Streamflow Maintenance
• Nutrient Transformation
• Sediment and Other Particulate Retention
• Shoreline Stabilization
• Stream Shading
• Ground Water Influence
• Carbon Sequestration
• Pathogen Retention

Habitat Functions:

• Fish Habitat
• Waterfowl/Waterbird Habitat
• Shorebird Habitat
• Interior Forest Bird Habitat
• Amphibian Habitat
• Conservation of Rare and Imperiled Wetlands & Species

These functions can help us strategize on restoration and protection opportunities. By using the NWI, you are able to estimate future wetland loss, prioritize invasive species treatment in/near sensitive wetlands, and identify wetland opportunities to support stormwater management. These are just a few examples of how the NWI tool can be used.

Currently, the National Wetland Inventory is ready for download from SEMCOG’s Open Data Portal. A final report with detailed methodology is in the final stages of the process. Once EGLE has updated the NWI, we can use this tool to assist with our Environmental Sensitivity Analysis tool, as well as support the analysis of critical wetlands and restoration priorities.

Wetlands are amazing places to explore for their abundant variety of flora and fauna. The abundance of water in wetlands, however, can make them challenging to explore on foot. This is why many of Southeast Michigan’s parks and recreation providers have installed facilities such as boardwalks to enable easier access. Visit one of Southeast Michigan’s wetlands for yourself!

Begin your wetland exploration right now using Southeast Michigan Trail Explorer to check out Crosswinds Marsh