Watersheds in the Great Lakes

Improving the Rivers and Streams that Feed the Great Lakes

Story Highlights
  • Watersheds in the Great Lakes basin have been altered through the implementation of dams, ditches and drains, causing diminished water quality and physical barriers for spawning fish.
  • Improving the quality and linkages to watersheds results in cleaner water, fewer beach closings, reduced water treatment costs, flooding prevention and a more resilient natural system.
  • The Great Lakes Project is working with landowners, removing physical obstructions and conserving key places to remediate wide-spread issues.

Every rippling creek, meandering stream or tumbling river is part of a watershed. Within the Great Lakes basins, the lakes themselves are the ultimate destination of these waterways and all they have collected along their way.

Unfortunately, they are collecting a lot. Water’s hydrology, or the way it flows, has been altered with the implementation of dams, drains and ditches. These alterations cause water to pulse through watersheds and pick up high amounts of sediments and nutrients.

In the past, these sediments and nutrients would have been filtered out as the water slowly seeped through the wetlands and other naturally vegetated areas.

The watersheds themselves are also altered and damaged. This damage trickles down to the Great Lakes themselves. Some coastal habitats are inundated with too much sediment from farm fields, leading to murky waters that render it uninhabitable for many species. High levels of nutrients from fertilizer run-off result in algal blooms that can cause beach closures and further stresses for aquatic species.

Besides the diminished water quality and quantity, there are physical changes to the Great Lakes watersheds. Fish are unable to access spawning areas upstream to produce the next generation because they’re cut off by dams, poorly-constructed culverts or too shallow waters.

The Great Lakes Project is developing solutions to remediate many of these widespread changes, while recognizing the inextricable link between watersheds and the lakes themselves, implementing projects to:

  • Work with farmers and other landowners to improve the flow of water: Approaches include reconnecting floodplains; restoring wetlands buffers; and redesigning drainage ditches that mimic the function of natural rivers.
  • Break down physical obstructions: Removing or modifying problematic dams and culverts will improve habitat, allowing aquatic species to move into prime feeding and spawning areas.
  • Conserve key places: Maximizing conservation outcomes by focusing our traditional acquisitions on wetlands and headwater streams.
  • Target investments at the watershed scale for optimal impact and outcome: Development of a science-based prescription and targeted application of conservation practices across an entire watershed—to deliver an optimal return on investment and measureable outcome of estuary improvement downstream.
  • Leverage through learning: Each of these projects provide lessons for the Conservancy’s future approaches as well as for our partners in the Great Lakes and beyond. Conducting complementary research will determine which remedies will have the greatest impacts locally and downstream and how much on-the-ground action will be needed to achieve system-level results.

Improving the quality of watersheds pays huge dividends not just for biodiversity. Cleaner water results in fewer beach closings—a big draw for the region’s annual 60 million tourists. And, it reduces the cost of water treatments, prevents flooding and helps the entire system to be more resilient and adaptable to future changes.