Welcome and thank you for visiting our website! Here you’ll find useful information about phosphorus (P) in agricultural contexts. We recommend exploring the sections in the order listed on the left side of the page for a full overview of how phosphorus relates to farming and lake health. However, you can explore the site’s content in any order, so follow your interest!

Graphic depicting the various landscape contributions of phosphorus from the Maumee River into Lake Erie. Source: Great Lakes HABs Collaborative.

Phosphorus pollution in Lake Erie originates from two primary sources: point sources, such as wastewater treatment facilities, and nonpoint sources, including agricultural runoff from farms. Point sources, which come from specific and identifiable locations, are easier to monitor and regulate. Over the past decade, investments in phosphorus removal technology at facilities like the Great Lakes Water Authority in Detroit and smaller wastewater treatment plants throughout Southeast Michigan have significantly reduced phosphorus contributions from point sources. These efforts have allowed Michigan to meet a 20% reduction target in phosphorus loading, a key milestone achieved in 9 of the last 10 years. Although this site focuses on the mitigation of nonpoint sources, point sources still contribute to the overall phosphorus load, meaning continued diligence in maintaining these reductions is essential.

This website is presented by the Western Lake Erie Basin Advisory Group. We hope the information here will help you understand phosphorus and do what you can to protect Lake Erie.