Sentinel Lake Assessment Report St. James Lake (83-0043) Watonwan County, Minnesota

The Minnesota Pollution Control Agency (MPCA) is working in partnership with the Minnesota Department of Natural Resources (MDNR) on the Sustaining Lakes in a Changing Environment (SLICE) Sentinel Lakes Program. The focus of this interdisciplinary effort is to improve understanding of how major drivers of change such as development, agriculture, climate change, and invasive species can affect lake habitats and fish populations, and to develop a long-term strategy to collect the necessary information to detect undesirable changes in Minnesota Lakes (Valley 2009). To increase our ability to predict the consequences of land cover and climate change on lake habitats, SLICE utilizes intensive lake monitoring strategies on a wide range of representative Minnesota lakes. This includes analyzing relevant land cover and land use, identifying climate stressors, and monitoring the effects on the lake's habitat and biological communities. The Sentinel Lakes Program has selected 24 lakes for long-term intensive lake monitoring (Figure 1). The "Deep" lakes typically stratify during the summer months only. "Shallow" lakes are defined as mixing continuously throughout the summer. "Cold Water" lakes are defined as lakes that either harbor cisco, lake whitefish, or lake trout and are the focus of research funded by the Environmental Trust Fund (ETF). "Super sentinel" lakes also harbor cold-water fish populations and research on these lakes is also funded by the ETF. St. James was selected to represent a shallow lake in the Western Corn Belt Plains (WCBP) ecoregion. St. James is a 83 hectare (206 acre) lake, located near the city St. James, Watonwan County, within the Minnesota River basin watershed. The lake has a maximum depth of 4.9 meters (16 feet) and a mean depth of 1.2 meters (4 feet). The lake is 100% littoral with two public accesses on the south shore of the lake. The total contributing watershed for St. James Lake is 945 hectares (2,337 acres). Frequent dredging in the northern basin of the lake since 1971 has increased the maximum depth of the lake by 10 feet (3.05 Meters).