CRAWFORD COUNTY - E.coli readings in the surface waters of Boydtown and Richland Creeks in Crawford County were measured by Crawford Stewardship Project (CSP) in the month of October at 82,000 and 19,000 colony forming units respectively.
The area had experienced large amounts of rain and flooding in late August, and then large rainfalls on-and-off throughout the month of September.
“To put that in perspective, the average E.coli reading for a body of surface water should not be over 126 colony forming units,” Forest Jahnke of the Crawford Stewardship Project told members of the Crawford County Land and Water Conservation Committee on Tuesday, Nov. 13. “E.coli readings in bodies of surface water should never go above 410 colony forming units more than 10 percent of the time, and in other parts of the state, if a reading reaches 750 they’ll issue an advisory, and if it goes above 1,000, measures such as closing of beaches are implemented.”
Proposed change
Typical measurements of water for contaminants from fecal sources such as manure or human septic waste are expressed in terms of ‘colony forming units.’ E.coli, the constituent of fecal contamination most dangerous to humans, is a microbiological subset of the overall category ‘coliform, and is another contamination indicator commonly measured and described in reports.
The state is currently engaged in a process to consider changing their standard to match that of the U.S. EPA, as expressed in their ‘Recreational Water Quality Criteria’ 820-F-12-058.
The current state standard measures fecal coliform, which can include E.coli, and not E.coli itself as a distinct sub-component. So the state standard for fecal coliform measured in surface or groundwater would be expressed as “the fecal coliform count may not exceed 200 colonies per 100 ml as a geometric mean and may not exceed 400 colonies per 100 ml in more than 10 percent of the samples during any month.”
Creeks measured
Boydtown Creek, located in southeast Crawford County, flows for approximately 1.7 miles in a southerly direction before reaching the Wisconsin River at Boydtown (between Boscobel and Wauzeka). This stream originates at a large spring (approximately 700 gallons per minute) in its upper end, and has an average gradient of 40 feet per mile.
After Boydtown Creek reaches Highway 60, the gradient is greatly reduced, and it flows through wetlands adjacent to the Wisconsin River. Boydtown Creek is a Class II trout stream for one mile upstream of Highway 60, and then Class I for the remaining 0.7 miles. The creek is an exceptional resource water above Highway 60.
Richland Creek, located in southeast Crawford County, flows for nine miles in a southerly direction before reaching the Wisconsin River near Boscobel. This stream has a gradient of 55 feet per mile and drains steep forested hills with agriculture found mainly in the valleys. Richland Creek is a Class II trout stream for its entire length upstream of Highway 60.
The most recent biological survey, conducted in 1965, documented stocked brook, rainbow, and brown trout as well as northern pike, grass pickerel and rock bass. Some natural reproduction of brown trout was noted. Many springs were observed along the entire length of Richland Creek during this survey.