Wisconsin's Green Bay suffers a large dead zone each year, threatening fish and wildlife. We're developing new partnerships and solutions to restore the bay.

Every summer, Wisconsin’s Green Bay in Lake Michigan suffers from a large ‘dead zone.’ Imagine: an area under Green Bay’s surface so low in oxygen that it can’t support life. The cause? Algae fueled by runoff pollution that flows into the bay.

Runoff pollution fuels algal blooms, causes dead zones

Every time it rains, runoff pollution carries excess nutrients into the streams and rivers that flow into Green Bay. The nutrients come from urban and suburban sources, like sewage treatment plants, and rural sources, like fertilizer and manure spread on farm land.

Too many nutrients are unhealthy for the bay, fueling large algal blooms. When the algae die and decompose, it uses up the oxygen in the water. Too little oxygen in the water can harm the fish and other life living under the surface of the bay.

Runoff pollution is preventable

Runoff pollution is preventable. Scientist have clearly shown that limiting runoff pollution will significantly improve the health of the bay.

The best place to stop pollution is at the source. Farmers are finding new ways to keep the fertilizer and manure spread on farm land to grow crops on the land and out of waterways. Preventing pollution at the source is the least expensive way to keep nutrients out of the bay and shrink the dead zone.

Developing new partnerships and solutions

The Alliance is helping shape solutions to this problem. We bring together farmers, government agency officials, businesses, and technical experts to develop ways to prevent run-off pollution. We also find ways to make it easy and cost-effective for farmers to implement new solutions.

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