Bacteria Monitoring in the Marengo River watershed - NOR_09_CMP15


This project will coordinate efforts with the Bad River Watershed Association and the Bad River Department of Natural Resources to conduct widespread monitoring of bacteria in the Marengo River, a class III trout stream that flows into the Bad River in the Lake Superior basin. In some locations of the river, partners and citizens have concerns about negative water quality impacts from raw septage inputs and nonpoint source pollution associated with poor land use. LTE and FTE staff will collect bacteria data on the Marengo River and its tributaries for two months during the summer 2015 field season. The Bad River Tribe's Natural Resources staff (BRNR) will be sampling the Marengo River at Reimer Road and at Government Road this summer. The proposed project will compliment that effort.


Bacteriological monitoring of the Marengo River and tributaries by the Bad River Watershed Association and the Bad River Natural Resource Dept. has shown high levels of E. coli are often present, especially during runoff events. Since 2007, BRWA has sampled E. coli on 162 sampling events across 20 locations in the Marengo River watershed. E. coli levels exceeded 126 colonies/100 ml on 70 occasions at 12 of those sites. E. coli levels exceeded 1000 colonies on 15 occasions at 7 of those sites. Livestock and residential wastewater systems appear to be the sources. The objective of this project is to conduct additional bacteria monitoring consistent with NR 102 to determine if water quality standards are being exceeded, and if so, to consider adding a section of the river to the 303d list of impaired waters. Three sites will be sampled on the Marengo River and its tributaries. Samples will be tested for both fecal coliforms and E. coli to help establish a local relationship between the two tests, and to allow better utilization and assessment of past E. coli test results available. Field tests will include conductivity, dissolved oxygen, temperature, and transparency.


If sampling shows that the Marengo River exceeds the WisCALM standards for water quality (bacteria), it will be considered for inclusion on the next cycle of 303d impaired waters list updates. Data will be compiled and analyzed and a final report will be entered into SWIMS. This project will build a coalition of supporters to address bacteria contamination in the Marengo River watershed among the Bad River Tribe, Bayfield County, the BRWA and their members, and the WDNR. This broad support will encourage local action to address any concerns that are found.

Study Design

Sampling frequency was determined in order to satisfy requirements in NR 102, which states that samples are required at least 5 times per month. Fecal coliform, E. coli, temperature, transparency, DO, pH and conductivity will be monitored at all sites during two months from May to September 2015, with special attention to runoff events. Other parameters will be sampled during field events with a multi parameter probe. Site selection was informed by previous data collected in the Marengo River watershed and by partner concerns. Monitoring sites are distributed throughout the lower reaches of the Marengo River, and on tributaries where there may be potentially impacted sites. Rationale for sampling and potential sampling locations are listed below. 1. BRWA and BRNR have recorded high levels of E. coli in an unnamed tributary near the Village of Marengo - SITE 10033482: Marengo River at Ensinger Rd. (downstream of R.R. tracks) 2. Bayfield County Zoning contacted the WDNR in 2014 about possible drainage from septic tanks into an unnamed tributary of the river and concerns about possible well contamination and human illness - SITE10030744: Unnamed tributary and County E near Four corners Store Road 3. Expansion of dairy operation in the Trout Brook watershed SITE 10022077: Trout Brook Cty C.

Related Reports

Run Project Summary Report
View Umbrella-Projects
View Related-Projects

TMDL/303d Projects
Identify Impaired Waters
Final Report Needed
Reports and Documents
Marengo River Photo WBIC 2921100
Report of E. coli sampling in the Marengo River and its tributaries in 2015
Bacteria Monitoring in the Marengo River watershed - NOR_09_CMP15
Activities & Recommendations
Monitor Water Quality or Sediment
Bacteria monitoring in the Marengo River and tributaries
ATTAINS Follow-up monitoring conducted
Bacteria Monitoring in the Marengo River watershed WBIC 2911900