Lake Assessment Program - Rush Lake, Otter Tail County, Minnesota

Document
Description
Rush Lake is located on the Otter Tail River in Otter Tail County, near Perham, MN. This lake has a surface area of 5,338 acres and a maximum depth of 68 feet. Mean depth of the lake is 12 feet. The immediate watershed of Rush Lake is approximately 12,633 acres (including the lake surface area). Land use in the watershed is characterized by open water/marsh (43 percent), cultivated (34 percent), forested (15 percent), grassland/pasture (6 percent), and residential/urban areas (the remaining 2 percent). These land use percentages are typical of what would be expected for lake watersheds in the North Central Hardwood Forests (NCHF) ecoregion of the state. Rush Lake was sampled during the summer of 1998 by Minnesota Pollution Control Agency (MPCA) staff and Rush Lake Association members. Water quality data collected during the study revealed a summer-mean total phosphorus concentration of 26 ?g/l, chlorophyll-a concentration of 11 ?g/l, and a Secchi transparency of 6.5 feet. All three of these values are well within the typical range exhibited by reference lakes in the NCHF ecoregion. Total phosphorus, chlorophyll-a, and Secchi transparency all help to characterize the trophic status of a lake. For Rush Lake, these measures indicate mesotrophic-eutrophic conditions.
Date Issued
2005
Number of Pages
34
Decade
Author
Rights Holder
Minnesota Water Research Digital Library
Rights Management
Public Domain