Water Quality Degradation in the Chisago Chain of Lake, Chisago County Minnesota
The priority was simple: Keep the Chisago Chain of Lakes swimmable and fishable.
Several of those lakes are impaired because of excess nutrients such as phosphorus. Many others within the Chisago Lakes Chain of Lakes Watershed show increasing phosphorus levels, which could lead to impairment.
The plan — devised by the Chisago Soil & Water Conservation District and made possible through two grants — leveraged partnerships with the cities of Lindstrom, Center City, and Chisago City; Chisago County; the Chisago Lakes Lake Improvement District (CLLID); agricultural landowners and city residents.
Using GIS analyses and water quality models, SWCD staff systematically completed stormwater assessments for all urban and rural areas within the Chain of Lakes Watershed. Field verifications and meetings with landowners followed. The assessments yielded lists of specific best management practices (BMPs) and projects, ranked by cost effectiveness. Armed with that data, SWCD staff applied for and was awarded an $887,632 Targeted Watershed grant in 2015 to address urban and agricultural runoff, and gully/ravine erosion. The grant period runs through 2020.
The Targeted Watershed Program allows local government units to employ a variety of concentrated management actions not limited to structural BMPs. Implementation of the Chisago Chain of Lakes project includes the following:
- Managing urban stormwater runoff through 40 projects such as rain gardens, iron-enhanced sand filters, catch basins retrofitted with filters, and rock-lined channels.
- Installing 25 agricultural projects such as water and sediment control structures, filter strips, waterways, and gully stabilizations.
- Using incentive payments to initiate cover crops and permanent vegetative plantings, plus more targeted and more frequent city street sweeping.
Overall the project will reduce at least 690 pounds of total phosphorus, which is 11 percent of the Total Maximum Daily Load goal. The SWCD is gaining momentum as it positions itself for the next phases of the project