Under the Great Lakes Water Quality Agreement, the U.S. and Canada have agreed to work together to reduce the amount of phosphorus entering the western and central basins of Lake Erie by 40% (from 2008 levels). ErieStat will track progress toward this goal. The governments of Michigan, Ohio, and Ontario have agreed to achieve the reductions by the year 2025.

Why Lake Erie needs our help

Approximately 11 million citizens rely on Lake Erie for drinking water. Clean, safe water is essential to Lake Erie’s vital role in supporting tourism, commercial and recreational fishing, agriculture, and manufacturing.

Nutrients are essential for growing our food and supporting a healthy ecosystem. However, excess phosphorus entering Lake Erie contributes to the formation of harmful algal blooms and low-oxygen “dead zones,” which can be dangerous for fish, wildlife, pets and people.

Maumee River at Toledo, Ohio, September 25, 2017. Photo by Toledo Aerial Media.

ErieStat is an online tool that tracks total and dissolved phosphorus entering Lake Erie’s western and central basins from selected tributaries. These trends appear under the “Results” menu. ErieStat also shares information on the strategies and investments intended to achieve the shared goal of phosphorus reduction in western and central Lake Erie.

Why Lake Erie Matters

Why Lake Erie Matters

Summer Fun

Estimates indicate that algal blooms could cost the Canadian Lake Erie basin economy $272M annually. In the U.S., the economic impact of the 2011 bloom resulted in an estimated cost of $71M.

Summer Fun, Ashtabula, Ohio (Dee Riley)


Major cities depend on Lake Erie for drinking water, recreation and commerce.

Cleveland, Ohio Aerial Landscape (© Pedro Gutierrez/Shutterstock)

Catching Fish

Lake Erie supports a $1.5 billion sport fishery and is considered the most valuable freshwater commercial fishery in the world.

Fisherman with freshly caught walleye in Lake Erie (© Ohio Sea Grant)

Who’s Helping

Convened by the Great Lakes Commission, representatives from federal, state, and provincial government agencies, as well as leading academic institutions, are contributing to the development of ErieStat.

How We Work

Blue Accounting uses metrics and relevant data to measure progress toward shared goals. For ErieStat, key water quality metrics were selected to track progress toward the shared phosphorus reduction goal. These metrics were selected to allow tracking of both total and dissolved phosphorus contributions from tributary rivers and streams to the lake. Water quality metrics are a starting point; additional metrics are anticipated in the future to measure progress of phosphorus control efforts on Lake Erie and the surrounding landscape.

ErieStat will also showcase strategies and investments contained within the U.S. and Canadian governments’ Domestic Action Plans being developed under the Great Lakes Water Quality Agreement. For more about the Domestic Action Plans, check out our Strategies page or download plans from the Resource page by searching for “plans.”

Where We Work

Where We Work

Lake Erie sub-basins

Lake Erie is the shallowest, warmest, and most productive of the five Great Lakes. The lake is divided into three sub-basins: western, central, and eastern.

Priority watersheds for phosphorus control

Federal, state and provincial government representatives are working together under the binational Great Lakes Water Quality Agreement to develop strategies for controlling phosphorus contributions to Lake Erie. As part of that work, 14 priority watersheds have been identified for focused efforts toward controlling phosphorus.

Phosphorus on the landscape

Phosphorus enters Lake Erie and its tributary rivers and streams from a variety of sources. Over time, the ErieStat team will work together to report on the results of phosphorus control efforts taking place on the land in both urban and rural areas. Results will also be shared for the priority tributaries/watersheds and the lake itself.