Fish and Aquatic Life
The Marengo River curves through a region of lakes, wetlands, forest and high hills in the Gogebic Range, then flows down into a region of red clay soils and lands cleared for agriculture, before flowing into the Bad River Indian Reservation to meet the Bad River. The river drains more than 80 square miles of Bayfield county before crossing into Ashland county. Only one impoundment exists on the river. This 5-foot concrete overflow dam is at the head of a scenic rapids and falls area. About a mile below that, an abandoned granite quarry is part of an interesting scenic area that is privately held.
From: Turville-Heitz, Meg. 1999. Lake Superior Basin Water Quality Management Plan. Wisconsin Department of Natural Resources, Madison, WI.
Author Aquatic Biologist
Due to rapid runoff from its rather impervious soils, steep hills and rock outcroppings, the river experiences three-to-four-foot flood crests. Most of the stream is quite open with the only good cover found in deep pools. Stream bottom types vary, with muck and sand predominating in the extreme upper stream areas, rubble, gravel and boulders through the middle portion, while the lower reach is almost entirely unstable sand. Extensive beaver activity deteriorates trout habitat along the upper shrub-marsh areas. Muskrats also use the river as do nesting and migratory waterfowl. As the river passes into Ashland County, the stream passes through large stretches of agricultural lands and the clear water becomes turbid due to streambank pasturing. There are a number of quarries in this watershed, as well as the potential for logging activities. The variety of jurisdictions overseeing land uses can mean variability in management practices.
Past documentation indicates an effluent ditch near the community of Marengo carries septage to the river. The impact of this is unknown, and it is unknown if this ditch is open to human access or poses a risk to wild and domestic animals.
Author Lisa Helmuth
The Marengo River (2911900) from the outlet of Marengo Lake to Bad River Indian Reservation Boundary was assessed during the 2016 listing cycle; fecal coliform data exceeded criteria. This portion of the river is considered impaired.
Author Aaron Larson
The Great Lakes Indian Fish and Wildlife Commission released a survey report on purple loosestrife in the Bad River Watershed. The report documents significant loosestrife infestations, the worst of which is around High Bridge and portions of the Marengo River.
Author Lisa Helmuth
Wisconsin has over 84,000 miles of streams, 15,000 lakes and milllions of acres of wetlands. Assessing the condition of this vast amount of water is challenging. The state's water monitoring program uses a media-based, cross-program approach to analyze water condition. An updated monitoring strategy (2015-2020) is now available. Compliance with Clean Water Act fishable, swimmable standards are located in the Executive Summary of Water Condition in 2018. See also the 'monitoring and projects' tab.
Citizen-Based Stream Monitoring
Collect chemical, physical, and/or biological water quality data to assess the current overall stream health. The data can inform management decisions and may be used to identify impaired waters for biennial lists.
Watershed Mapping or Assessment
The Bad River Watershed Association is sponsoring a project that focuses on community outreach and the formation and direction of a Citizen Involvement Committee to guide the Marengo River Action Plan for the Marengo River watershed. The project is part of a broader Marengo River Watershed Partnership, which will identify, prioritize, and coordinate management actions. Specifically, the Citizen Involvement Committee will compile existing sociological surveys to prioritize public interests, develop conservation incentive program summaries for citizens, hold 5 focus group meetings with targeted audiences, and summarize and integrate focus group feedback into the Plan. The goal is to recruit 25 new members and 10 new organizational leaders through this effort. The final deliverable includes: a final report with 1) sociological survey(s) compilation, 2) conservation program summaries, 3) focus group meeting attendance summaries and minutes, 4) focus group roadmap for Plan integration, and 5) list of new members or leaders recruited.
Monitor Aquatic Biology
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.
Water Quality Planning
The Marengo River Watershed is located in central Ashland and south central Bayfield counties in the Lake Superior Basin of northern Wisconsin.
Wisconsin's Water Quality Standards provide qualitative and quantitative goals for waters that are protective of Fishable, Swimmable conditions [Learn more]. Waters that do not meet water quality standards are considered impaired and restoration actions are planned and carried out until the water is once again fishable and swimmable
Management goals can include creation or implementation of a Total Maximum Daily Load analysis, a Nine Key Element Plan, or other restoration work, education and outreach and more. If specific recommendations exist for this water, they will be displayed below online.
Monitoring the condition of a river, stream, or lake includes gathering physical, chemical, biological, and habitat data. Comprehensive studies often gather all these parameters in great detail, while lighter assessment events will involve sampling physical, chemical and biological data such as macroinvertebrates. Aquatic macroinvertebrates and fish communities integrate watershed or catchment condition, providing great insight into overall ecosystem health. Chemical and habitat parameters tell researchers more about human induced problems including contaminated runoff, point source dischargers, or habitat issues that foster or limit the potential of aquatic communities to thrive in a given area. Wisconsin's Water Monitoring Strategy was recenty updated.
Grants and Management Projects
|WBIC||Official Waterbody Name||Station ID||Station Name||Earliest Fieldwork Date||Latest Fieldwork Date||View Station||View Data|
|2911900||Marengo River||10043260||Marengo River at Wisco Rd||1/7/2013||7/5/2013||Map||Data|
|2911900||Marengo River||10012280||Marengo River - Marengo River At Wisco||6/27/2006||10/3/2007||Map||Data|
|2911900||Marengo River||10055654||Marengo R. 27m US Snake Trail Rd||Map||Data|
|2911900||Marengo River||10055122||Marengo River US Marengo Lake Road||5/27/2021||11/10/2021||Map||Data|
During survey work conducted as part of the coastal wetlands evaluation one rare species of macroinvertebrate was found and overall taxa richness was moderate (5-24 species) (Epstein 1997). At the survey site in Bayfield County, significant pollutant sources were identified from point sources, construction activities, livestock, barnyards and cropland. Significant silting may be affecting habitat quality.
This water was assessed during the 2014 listing cycle; biological sample data (i.e. macroinvertebrate or fish Index of Biotic Integrity (fIBI) scores) clearly met 2014 WisCALM listing thresholds for the Fish and Aquatic Life use.
Five monitoring sites on the river have collected biological data in the past five years (2008 through 2012). Fish IBI data on 2008 through 2013 indicated a mix of Fair, Good and Excellent values at three different stations. A macroinvertebrate value indicated "excellent" condition.
Author Lisa Helmuth
Marengo River is located in the Marengo River watershed which is 217.53 mi². Land use in the watershed is primarily forest (67.40%), wetland (15.30%) and a mix of grassland (11.60%) and other uses (5.70%). This watershed has 450.89 stream miles, 1,497.18 lake acres and 18,112.32 wetland acres.
Nonpoint Source Characteristics
This watershed is ranked Medium for runoff impacts on streams, Not Available for runoff impacts on lakes and Low for runoff impacts on groundwater and therefore has an overall rank of Low. This value can be used in ranking the watershed or individual waterbodies for grant funding under state and county programs.However, all waters are affected by diffuse pollutant sources regardless of initial water quality. Applications for specific runoff projects under state or county grant programs may be pursued. For more information, go to surface water program grants.