Sauk River Chain of Lakes Total Maximum Daily Load Report

This total maximum daily load (TMDL) study addresses nutrient impairments in 14 lakes of the Sauk River Watershed, which is located within the Upper Mississippi River Basin west and northwest of St. Cloud, Minnesota. These lakes do not meet Minnesota's water quality standards due to excessive nutrient concentrations and nuisance algal blooms. The project area of 925 mi2 (592,275 acres) is located in five counties of central Minnesota, with the majority in Stearns County. The impaired lakes are distributed along two converging flow paths: (1) the predominant Sauk River flowing from the north through the Sauk River Chain of Lakes (SRCL; 10 impaired lakes); and (2) the much smaller Eden Valley Creek (EVC) flowing from the south through four impaired lakes and then into Horseshoe Lake, the most upstream of the Sauk Chain of Lakes (Figure 1). The goal of this TMDL is to quantify the pollutant reductions needed to meet state lake water quality standards for nutrients in all of these lakes.