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Learn About Michigan's Wetlands

A lush wetland with clumps of green reeds scattered across the water. A power line runs in the background
Environment, Great Lakes, and Energy

Learn About Michigan's Wetlands

Most people are familiar with the cattail or lily pad wetlands found in areas with standing water, but wetlands also can be grassy meadows, shrubby fields, or mature forests. Many wetland areas have only a high ground water table and standing water may not be visible. Types of wetlands include deciduous swamps, wet meadows, emergent marshes, conifer swamps, wet prairies, shrub-scrub swamps, fens, and bogs.

This page offers resources about wetlands, including definitions, how to identify, mitigation and restoration, regulations, a list of frequently asked questions, and a Wetlands Map Viewer.

Wetlands project in Lenawee County - after (August 2013)

What are wetlands?

Wetlands are land with enough water under normal circumstances to support wetland plants or aquatic life.

Wetlands are usually referred to as a bog, swamp, or marsh.

Learn why wetlands are important
a wetland inventory map produced by WLSU

Are there wetlands on my property?

Wetlands are areas where land and water meet. Whether water is slightly above or below the surface of the land, the one thing that makes the difference when identifying whether or not an area is a wetland is the presence of water.

Land does not have to be wet all of the time in order to be defined as a wetland. In some cases, it will not be immediately obvious that a wetland exists. The presence of water will, however, cause a number of physical, chemical and biological characteristics to develop. These characteristics can be used to identify and locate wetlands.

Get the resources to find out
A low lying wetland with trees and tufts of grass emerging from the water

How are wetlands identified?

Identification of wetlands using the federal method involves three factors: how much wetland plants there are, hydric (wetland) soils, and signs of hydrology (presence of water). 

The presence of water (the hydrology) is necessary at certain times of the year for the development of a wetland. The timing, frequency, and level of saturation each year influences what kind of plants can grow in an area and the type of chemical and physical reactions which occur in the soil. 

Learn the technical definitions
View of a completed and established wetland mitigation site.

Wetland Mitigation

The purpose of "compensatory wetland mitigation" (commonly referred to as just "wetland mitigation") is the replacement of unavoidably lost wetland resources with man-made or restored wetlands.

The goal of wetland mitigation is replacing the functions and public benefits of the lost wetland as much as possible.

Technical details of wetland mitigation
Preview of the wetlands map viewer
Preview of the wetlands map viewer

Wetlands map viewer

Within this application, you will find information on land cover, soils, and the National Wetland Inventory. It is not intended to be used to determine specific locations and jurisdictional boundaries of wetland areas.


Launch web map

View the interactive map to explore the wetlands.

User guide

View the user guide for the wetlands map viewer.

Access data

The data used in the map is available to download and to view as a table.

Maps and data portal

Find all of EGLE's web maps and open data centralized to one location.

Frequently Asked Questions

  • Wetlands are transitional areas where land and water meet. Whether water is slightly above or below the surface of the land, the single controlling feature that makes the difference when identifying whether or not an area is a wetland is the presence of water.

    Land does not have to be wet all of the time in order to be defined as a wetland. In some cases, it will not be immediately obvious that a wetland exists. The presence of water will, however, cause a number of physical, chemical and biological characteristics to develop. These characteristics can be used to identify and locate wetlands.

    Because wetlands are identified according to the site-specific development of physical and biological conditions, an on-site inspection is always necessary to determine, with certainty, whether wetlands are present. Other information, such as Part 303 Wetland Inventory Maps, National Wetland Inventory Maps, County Soil Surveys, and aerial photos provide indications of where wetlands may exist. However, these may not include all wetlands and may identify areas that once were, but no longer are, wetlands. As a result, the actual conditions at a property will always take precedence over any information source.

    Part 303 Wetland Inventory Maps show the general location of wetlands in your county. However, because of the scale of these maps and the methods used to produce them, they cannot be used to accurately define the location and boundaries of wetlands on an individual parcel of land.

    Part 303 Wetland Inventory Maps

    When it is necessary to accurately identify the location of a wetland or its boundaries, a site analysis through the Wetland Identification Program or by a qualified consultant is needed.

    Wetland Identification Program

    Wetland Consultants

    If you have a proposed project and are uncertain if it will impact wetlands, a Pre-application Meeting with EGLE may be helpful.

    Pre-application Meetings

  • Michigan's wetland statute, Part 303, Wetlands Protection, of the Natural Resources and Environmental Protection Act, 1994 PA 451, as amended, defines a wetland as "land characterized by the presence of water at a frequency and duration sufficient to support, and that under normal circumstances does support, wetland vegetation or aquatic life, and is commonly referred to as a bog, swamp, or marsh. "Part 303 requires the department and local units of government to use the technical wetland delineation standards set forth in the United States Army Corps of Engineers January 1987 Wetland Delineation Manual, and appropriate regional supplements, in identifying wetland boundaries. Two regional supplements apply to Michigan: the Midwest supplement for portions of Southeast Michigan (portions of Hillsdale, Lenawee, Washtenaw, Livingston, Wayne, and Oakland Counties) and the Northcentral and Northeast Supplement, which covers the remainder of Michigan.

    The 1987 U.S. Army Corps of Engineers Manual

    Midwest Regional Supplement

    Northcentral and Northeast Regional Supplement

    Identification of wetlands using the federal delineation method primarily involves the determination of three factors: the predominance of wetland vegetation, hydric (wetland) soils, and signs of hydrology. The presence of water (the hydrology) is necessary at certain times of the year for the development of a wetland. The timing, frequency, and level of saturation each year influences the type of vegetation that can grow in an area and the type of chemical and physical reactions which occur in the soil.

    Knowledge about the plants in an area is essential for delineating wetlands. Wetland plants have adaptations or responses that allow them to survive, grow, and reproduce with their roots in water or saturated soils for at least part of a year. Conversely, many plants cannot survive in saturated conditions and are commonly referred to as upland plants. Due to the need to identify plant species, it is recommended that any wetland identification occur during the growing season. The National Wetland Plant List provides information about how often a plant occurs in wetlands and other useful information.

    A hydric soil is a soil that is saturated, flooded, or ponded long enough during the growing season to develop anaerobic conditions. This lack of oxygen in the soil can lead to the formation of certain observable characteristics in wetland soils, such as a thick layer of organic matter (non-decomposed plant materials) in the upper part of the soil column. Other observable features include oxidized root channels and redoximorphic features (concentrations and depletions of Iron and other elements). Field Indicators of Hydric Soils in the United States includes hydric soil indicators approved by the Natural Resources Conservation Service and the National Technical Committee for Hydric Soils (NTCHS) for use in identifying, delineating, and verifying hydric soils in the field. In addition, several Supplemental Hydric Soil Field Indicators for Michigan were approved by the National Hydric Soils Committee in 2012.

    EGLE offers a fee-based Wetland Identification Program (WIP) to assist landowners in identifying wetland and non-wetland (upland) areas on their property.

  • In accordance with Part 303, wetlands are regulated if they are any of the following:

    • Connected to one of the Great Lakes or Lake St. Clair.
    • Located within 1,000 feet of one of the Great Lakes or Lake St. Clair.
    • Connected to an inland lake, pond, river, or stream.
    • Located within 500 feet of an inland lake, pond, river or stream.
    • Not connected to one of the Great Lakes or Lake St. Clair, or an inland lake, pond, stream, or river, but are more than 5 acres in size.
    • Not connected to one of the Great Lakes or Lake St. Clair, or an inland lake, pond, stream, or river, and less than 5 acres in size, but EGLE has determined that these wetlands are essential to the preservation of the state's natural resources and has notified the property owner.

    The law requires that persons planning to conduct certain activities in regulated wetlands apply for and receive a permit from the state before beginning the activity. A permit is required from the state for the following:

    • Deposit or permit the placing of fill material in a wetland.
    • Dredge, remove, or permit the removal of soil or minerals from a wetland.
    • Construct, operate, or maintain any use or development in a wetland.
    • Drain surface water from a wetland.
  • Here are some clues that wetland might be present:

    • The ground is soggy or has standing water, even for just part of the year.
    • The soils are black or peaty.
    • The property is lower than surrounding land.
    • The land is flat without any grade changes.
    • The trees are tipped over due to shallow roots.
    • The property is near a pond, lake or stream.
    • The property failed a perc test or an engineered septic system is required.
    • The property is tax reverted.
  • Does information already exist for this property on the presence of wetlands, such as:

    • Are there wetland reports or delineations, or EGLE letters, permits, or denials for this property? A search of Site Map Explorer in the EGLE database MiEnviro may help.
    • Has a perc-test been done? If so, what were the results?
    • Information from owners or neighbors about standing water, flooding, drainage, muddy spots, etc.
  • Michigan's wetland statute, Part 303, Wetlands Protection, of the Natural Resources and Environmental Protection Act, 1994 PA 451, as amended, defines a wetland as "land characterized by the presence of water at a frequency and duration sufficient to support, and that under normal circumstances does support, wetland vegetation or aquatic life, and is commonly referred to as a bog, swamp, or marsh." The definition applies to public and private lands regardless of zoning or ownership.

    Most people are familiar with the cattail or lily pad wetland found in areas with standing water, but wetlands can also be grassy meadows, shrubby fields, or mature forests. Many wetland areas have only a high ground water table and standing water may not be visible. Types of wetlands include deciduous swamps, wet meadows, emergent marshes, conifer swamps, wet prairies, shrub-scrub swamps, fens, and bogs.

    Photos and Descriptions of Various Types of Wetlands

    Wetlands are a significant factor in the health and existence of other natural resources of the state, such as inland lakes, ground water, fisheries, wildlife, and the Great Lakes. Michigan's wetland statute recognizes the following benefits provided by wetlands:

    • Flood and storm control by the hydrologic absorption and storage capacity of wetlands.
    • Wildlife habitat by providing breeding, nesting, and feeding grounds and cover for many forms of wildlife, waterfowl, including migratory waterfowl, and rare, threatened, or endangered wildlife species.
    • Protection of subsurface water resources and provision of valuable watersheds and recharging ground water supplies.
    • Pollution treatment by serving as a biological and chemical oxidation basin.
    • Erosion control by serving as a sedimentation area and filtering basin, absorbing silt and organic matter.
    • Sources of nutrients in water food cycles and nursery grounds and sanctuaries for fish.

    These benefits, often referred to as wetland functions and values, often play a vital role in recreation, tourism, and the economy in Michigan. According to a 1991 United States Fish and Wildlife Service Wetland Status and Trends report, over 50% of Michigan's original wetlands have been drained or filled, thereby making the protection of remaining wetlands that much more important.

  • EGLE offers information on our web sites to help get you started including:

    • Maps of potential wetland areas on the Wetlands Map Viewer. This is a good place to start to get an idea what might be on the property. This map does not identify actual wetland, boundaries, or the need for a permit, so an on-site visit by a wetland professional is needed.
    • A list of Private Consultants that you may hire to identify presence of wetlands and if they are regulated.
    • EGLE Staff Contacts - Look for the Land/Water Permitting Staff Map. Staff for your County may have knowledge of the property and/or area, but cannot tell you for sure if wetland is present without a site visit.
  • The following EGLE services are available and detailed on the Wetlands Protection Program web site:

    • Pre-Application Meeting is an official request to meet with EGLE staff to discuss a project and determine if a permit will be necessary.
    • Wetland Identification Program offers wetland delineation services that includes a site visit to identify wetland boundaries and regulatory status.