The Maumee River is a major source of pollution in Lake Erie, mainly due to agricultural runoff carrying nutrients that lead to harmful algal blooms.

The main source of nutrient contamination in Lake Erie is the Maumee River, which flows through agricultural areas in Indiana and Ohio. It brings large volumes of nitrogen and phosphorus into the lake via animal waste and agricultural fertilizers. These overabundances of nutrients encourage toxic algal blooms that degrade water quality, threaten human health, and destroy marine life. The lake's nutrient levels deteriorate when there is a lot of rain because the runoff gets worse. The Maumee River's influence on Lake Erie emphasizes the necessity of efficient environmental and agricultural methods to reduce nutrient pollution and safeguard the ecosystem and water quality of the lake.