Madison, Wisconsin, area lake enthusiasts can expect cleaner lakes this year and into the future in part thanks to the 75,000 pounds of phosphorus that was removed from Dorn Creek, a main tributary to the Yahara River, the principal water source to the Yahara Lakes System, which comprise the Yahara River Watershed.

Dane County hired us in August 2017 to design the first 2.6 miles of the County’s proposed 33 miles of legacy sediment removal in creeks intertwining the Yahara Lakes system. This removal effort is often referred to as the “Suck the Muck” project and is intended to improve the water quality of the main bodies of the watershed, including lakes Mendota, Monona, Waubesa, and Kegonsa. This first project is located along Dorn Creek between CTH Q and CTH M in the Town of Westport, northwest of Lake Mendota.

The phosphorus-laden sediment went down as far as 4 feet and the contractor the County hired (PCi Dredging) removed more than 11,000 tons of sediment this past fall. The goal is to achieve cleaner lakes that help restore fish populations and facilitate enjoyment of the many natural aquatic amenities the geographic region has to offer.

Why remove phosphorus?

Although phosphorus is a necessary nutrient for living things, it can be harmful to water and aquatic life when in excess. High phosphorus concentrations can be partially attributed to the use of farm manure and fertilizer that gets washed into bodies of water through rainfall runoff. Once in the water, phosphorus is food for algae and when combined with sunny summer months, is the primary cause of blue-green algae blooms that consume oxygen in the water and hinder many of the other elements natural to an aquatic ecosystem, leading to a slimy green blanket on the lakes. Just 1 pound of phosphorus can generate up to 500 pounds of blue-green algae.

What’s next for the “Suck the Muck” project?

Dane County will continue the “Suck the Muck” project to complete the 33 miles of sediment removal from the phosphorus-laden waterbodies. This includes Token Creek, Sixmile Creek, Door Creek, Nine Springs Creek, and the Yahara River.