Clean Lakes 101: Healthy Land, Healthy Lakes
- 03/10/2021 8:00 am - 9:00 pm
Clean Lakes Alliance is hosting County Executive Joe Parisi and Dane County staff John Reimer and Kathy Kuntz as they review some of Dane County’s ongoing lake improvement initiatives in the Yahara Watershed. The Dane County Land and Water Resources Department leads and collaborates with organizations and agencies on innovative watershed scale approaches to improve water quality. These approaches vary in size and scope and include new technologies, research, and partnerships. Topics include:
Suck the Muck: Phosphorus concentrations in the stream sediments of Dorn Creek (northeast of Lake Mendota) are seven times greater than nearby crop fields. Much of the stream sediment is known as legacy sediment, deposits formed by erosion from farm fields accumulating over decades of farming. In the case of Dorn Creek, this sediment has existed since the late 1800s. For Lake Mendota, if the accrued legacy sediment remains at the bottom of the streams, it was calculated that it would take almost 100 years for the phosphorus to continue to leach out of the sediments and enter the lake. In order to reduce phosphorus concentrations and improve water quality decades sooner than 100 years, Dane County developed an innovative project to remove the phosphorus-laden sediment from the streambeds within the Yahara Watershed.
Yahara River Sediment Removal: Currently, water comes into the Yahara lakes faster than it goes out. Therefore, after repetitive and heavy rainfall events, the lake levels increase and can lead to flooding. The efficient movement of water through each lake is undermined by sediment build-up in the Yahara River. While sediment movement is a naturally occurring process, the accumulation of sediment in the Yahara River and lakes is greatly increased by human activity, including urban development and winter sand operations. Today, two inches of rain takes more than two weeks to leave the Yahara lakes system due to its sluggish nature.
Land Preservation: Dane County Parks has more than 12,000 acres of land that staff, volunteers, and partner organizations work to protect, improve, and restore. These restoration efforts include seed collection, controlled burns, forestry management, invasive species control, and land purchases.
Climate Change: In April 2020, Dane County issued an ambitious and comprehensive economy-wide climate action plan (CAP). The CAP lays out strategies for reducing greenhouse gas emissions from all sources by 50% by 2030 with the ultimate aim of net zero emissions by 2050. Benefits of achieving CAP objectives go beyond climate—many of the strategies outlined in the CAP also yield substantial benefits to our lakes.
Categories: Parks, Talk or Workshop