High Water Temperatures Recorded on Black Earth Creek and Proposed USGS Monitoring Cutback

Andy Morton (BECWA Board of Directors) and Nick Bower (CARPC)

One of the highest water temperatures (77 degrees F) was recorded on July 27, 2026 and several other times this summer at the USGS Black Earth Creek (BEC) water quality monitoring station located just upstream from Park Street in the Village of Black Earth. In addition, stream temps this summer reached over 70 degrees F at upstream locations on BEC. This location is within the Class 1 section of the stream, where natural reproduction is sufficient to support the fishery.

These high temperatures are above optimal water temperatures for brown trout (approximately 60 to 65 degrees F). Relatively long durations of higher temperatures can be stressful for trout. This finding underscores the importance of maintaining the groundwater fed springs that flow into BEC and are vital for the health of the trout fishery and cold-water ecosystem.

The cooperative USGS watershed monitoring program, which is an important management tool for sustaining this cold-water resource, will be cut back in 2027, due to budget shortfalls. One monitoring station will be dropped (upstream of Cross Plains) and the parameters monitored at the remaining three stations will be limited to temperature, dissolved oxygen and discharge.

Black Earth Creek temperature, 7/21/26 to 8/21/26, from the USGS station at the Park St Bridge in Black Earth. The peak of 77 degrees F was recorded July 27, 2026. Provisional data, subject to revision.