The 2023 reports are in on Huron River chemistry and flow monitoring! HRWC volunteers, staff, and partners have worked hard collecting and analyzing data to evaluate the health of the Huron River and four Detroit River tributaries. We compiled the results of these efforts into three reports on the chemistry of these waterways: HRWC’s Washtenaw and Wayne County Chemistry and Flow Monitoring reports as well as a 2023 Lake Erie Watershed Health: Field Season Report produced as part of HRWC’s involvement with the Lake Erie Volunteer Science Network (LEVSN).

Infographic highlighting 3 findings from the 2023 data reports.

The Chemistry and Flow Monitoring reports evaluate data collected over 20 years in Washtenaw County and 11 years in Wayne County to evaluate non-point source pollution in these counties and help local municipalities track pollution and drive restoration efforts. The LEVSN report, on the other hand, assesses a subset of the data collected in both counties in 2022 and 2023 to determine spatial trends within the watersheds and compare them to other river systems within the Lake Erie basin. Three reports may be daunting to sift through. To get to the point, we extracted three major findings:

Phosphorus concentrations are on the decline in the Huron River and some tributaries, but are still above desired target concentrations to combat harmful algal blooms in downstream lakes.

  • Data shows that annual average phosphorus concentrations at sites in the Huron River in Ypsilanti near Ford Lake and in Rockwood near Lake Erie have declined over time. 2023 average phosphorus concentrations are near the original regulatory target concentration of 0.05 mg/L (50 µg/L) for Ford and Belleville lakes, but above the updated target of 0.03 mg/L (30 µg/L) set in 2019.
  • Some Huron River tributaries upstream of Ypsilanti, including Boyden, Honey, Allen, and Traver creeks, also show declining trends in phosphorus over time. This suggests phosphorus carried in stormwater runoff may be decreasing.

Bacteria levels in the main stem of the Huron River meet state recreational standards for partial and full body contact, but tributaries of the Huron and Detroit Rivers only meet these standards in about 25 – 75% of samples. Some tributaries of the Huron River show improved levels over time, though.

  • Data shows that, in the last four years, bacteria levels in the main stem of the Huron River have never exceeded the partial body contact limit and have only exceeded the full body contact limit eight times (twice at Riverside Park in Ypsilanti and six times at Fort Road in Rockwood).
  • Bacteria levels in the tributaries of the Huron and Detroit Rivers are a bit more complicated. Water recreators should use caution when coming in contact with smaller streams and should disinfect after exposure, especially after storms.

Conductivity, a general indicator of water quality, is high across the Huron River watershed and four Detroit River tributaries, especially in urban areas, and is high compared to most other watersheds in the Lake Erie Basin. This is likely due to road salt inputs.

  • The Huron River conductivity data exceeds healthy water conductivity standards 25 – 50% of the time throughout the period of record suggesting potential pollution and impacts to macroinvertebrate communities. Exceedances are more frequent in the tributaries that drain urban areas and are highest during hot and dry weather conditions.
  • High conductivity values correspond with high salt levels as measured by chloride concentrations. Salts can enter the streams and rivers through contaminated ground water or runoff directly from excessive applications of road salts in the winter.

For detailed information about these findings and additional results, check out the full reports linked below.

  1. Chemistry and Flow Monitoring Results – Washtenaw County
  2. Chemistry and Flow Monitoring Results – Wayne County
  3. 2023 Lake Erie Watershed Health: Field Season Report

All the data presented in these reports was collected by dedicated volunteers and supported by our municipal watershed partners including the Middle Huron Partners (MHP) and the Alliance for Downriver Watersheds (ADW). We will also dig into these data more and discuss what you can do to improve the health of the Huron River in an upcoming blog series about the newly released Southeast Michigan Watershed Report Cards.

Learn more about our volunteer Chemistry and Flow Monitoring Program on our program web page. The 2024 monitoring season is in full swing. Subscribe to our newsletter to stay informed about future volunteer opportunities.