50% phosphorus reduction needed to clean up the lakes
The Yahara Clean Strategic Action Plan for Phosphorus Reduction (2012) includes 14 actions designed to meet a UW Center for Limnology recommendation for a 50% reduction in the average annual phosphorus input to each of the lakes. The recently released phosphorus report card shows total phosphorus reduction progress for 2018.
Phosphorus is a naturally occurring element and essential plant nutrient found in material such as fertilizer, leaves, soil, and animal waste. When it enters our lakes from agricultural and urban runoff, it is known to promote the growth of noxious cyanobacteria blooms that can produce toxins of human and animal health concern. It takes as little as one pound of phosphorus to grow of 500 pounds of algae. Cyanobacteria blooms cause beach closures and soupy green water that limit enjoyment of the lakes.
Actions for our lakes
In 2018, the community continued to take action in urban and rural areas to reduce phosphorus runoff. Farmers are adopting best management practices through the work of Yahara Pride Farms, Dane County Land and Water Resources Department, the Yahara Watershed Improvement Network’s (WINS) adaptive management project, and with grant support from Clean Lakes Alliance.
In urban areas, municipalities have put in stormwater facilities, restored and maintained wetlands and natural areas, addressed erosion in urban streams, and educated the public on the need to keep leaves out of the street. These actions need to accelerate if we are going to meet our water quality goals for the lakes.