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Protecting Northern Michigan's ​Water Resources


A watershed is the area of the land's surface that drains to a particular water body. Boundaries are generally based on high elevations.

For instance, the continental divide is North America's most famous watershed boundary. On the east side of the continental divide, the rivers and other water bodies all drain to the Atlantic Ocean. On the west side of the continental divide, all of the waters drain to the Pacific Ocean.

Watershed Size
Watersheds may be characterized by their size. Large watersheds may encompass thousands of square miles; small watersheds may include only several square miles. The Lake Michigan Watershed, a large watershed, includes 45,598 square miles. This gives a watershed-to-water surface area ratio of about 2:1, which is relatively low. Lake Michigan’s water originates from precipitation falling throughout its watershed.

Watershed Features
The features of a watershed influence the characteristics of its receiving water body. These features include things like:

  • Soils
  • Vegetation
  • Climate
  • Topography
  • Geology
  • Human Land Use
Because each watershed has different conditions, each lake and stream is unique. For instance, because of the limestone which is prevalent throughout much of the Lake Michigan basin, the water has high levels of calcium and magnesium (termed hardness), and carbonates (which create alkaline conditions), and as such, is well buffered against acid precipitation.

Water Quality and Pollution
The water quality of a lake is a reflection of the activities surrounding it within its watershed. There are two major types of pollution: point source and nonpoint source.

Point source pollution comes from an easily identifiable source, such as a discharge pipe from a factory.

Nonpoint source pollution is pollution that comes from more diverse and diffuse sources that are not usually so obvious. Examples include soils that are eroded as a result of human activities or substances which have been applied to land, such as fertilizers. Nonpoint source pollution reaches surface water primarily through runoff from rainfall or melting snow that picks up contaminants from the land. It can also include subsurface drainage such as leachate from septic systems, and airborne pollutants, such as emissions from cars and power plants that produce acid rain.

Learn more about a specific watershed

Watershed Management Plans

2024 Mullett Lake, Lower Black/Cheboygan Rivers Watershed Management Plan
2022 Larks Lake Watershed Management Plan
2022 Elk River Chain of Lakes Watershed Management Plan
2021 Coastal Grand Traverse Bay Watershed Plan
2018 Burt Lake Watershed Management Plan
2012 Lake Charlevoix Watershed Management Plan

Watersheds in Our Service Area

Click image to enlarge

EGLE/EPA approved watershed management plans:

Burt Lake Watershed Management Plan

Duncan-Grass Bays Watershed Management Plan

Elk River Chain of Lakes Watershed Management Plan (in-progress)

Lake Charlevoix Watershed Management Plan

Little Traverse Bay Watershed Protection Plan

Mullett Lake Watershed Management Plan (in-progress)

Other Plans:

Black Lake Watershed Stewardship Initiative

Cheboygan River Watershed Habitat Partnership Conservations Area Plan

Grand Traverse Bay Watershed Management Protection Plan

Larks Lake Watershed Plan

Lower Black River Watershed Management Initiative

Mullett Creek Watershed Management Plan

​Paradise Lake Management Plan

Pickerel-Crooked Lakes Nonpoint Source Pollution Management Plan

Stover Creek Restoration and Management Plan

Tannery Creek Watershed Management Plan