Measuring the health of a trout stream using the Hilsenhoff Biotic Index (HBI).

https://wiflyfisher.com/Measuring-the-Health-of-a-Trout-Stream.asp

There are some ways to help find the data that is deep within some websites.

Go here and click on "Rivers, Lakes Bays, and Harbors", and then select a County, then select a river/creek. To explore click on the tabs to find past reports if they exist.
https://dnr.wi.gov/water/default.aspx

Today, many of the studies for the WDNR are conducted by volunteers. They are sampling about 100 macroinvertebrates and identifying only to the "family" level. This is called "Family Biotic Index". It is done because it is much faster and less costly to do. Although it is less accurate than the HBI, which identifies macroinvertebrates taxa to the genera/species level.

Some stream health reports are also found here: https://wateractionvolunteers.org/, but not for HBI, more for water quality assessments.