Today 5/8/20 I did our first Secchi Disc Test of the Year. Despite the high Winds making waves and creating less than ideal conditions I recorded our Deepest reading @ 18’6″
Water Quality Testing
https://micorps.net/wp-content/uploads/sites/63/2020/02/CLMP-Harwood-Cass-140201.pdf
Harwood Lake has a great start to tracking its water quality thanks to Jim Kings. Jim attended (self-funded) the Michigan Clean Water Corps (MiCorp)-Michigan Lake Stewardship Association 2-day training / certification programs for water quality testing plus registered Harwood Lake for statewide monitoring.
- 2019 – Included water clarity/transparency and phosphorous level testing conducted by Jim
- 2020 – Expanded testing and analysis of Harwood Lake water quality and supporting environment planned for 2020. Specific testing – and need for volunteers – will be announced when warm weather returns!
Water Clarity -Secchi Disc Testing: September 20th, the Summer testing came to an end. Jim Kings conducted and submitted for public record, 19 Secchi Disc tests. The year started with 9′ of clarity/transparency and finished with 15′ clarity – weekly results follows. The average depth was 11.5 feet (3.5 m) for the 2019 summer which puts Harwood Lake into the Oligotrophic range – Trophic State Index (TSI) provided after Secchi Disc Results.
Phosphorous Level – Jim submitted water sample to DNR in Plainwell MI for Michigan Lake Stewardship Association (MLSA) to analyze; results pending ….. will keep you updated.
As just a FYI: What is phosphorous and why test?
Phosphorous is essential for plant life. It is also a constituent of agricultural fertilizers, manure and organic matter from sewers/septics. A sign of excess phosphorus in a lake is excess algae in lake, as experienced by Driskell Lake in Jones MI. Testing phosphorous levels help us to be proactive and avert such negative consequences.
Trophic State Index
The Trophic State Index (TSI) is a classification system designed to “rate” individual lakes, ponds and reservoirs based on the amount of biological productivity occurring in the water. The index can provide a quick idea about how pro-ductive a lake is by its assigned TSI number.
The TSI of a body of water is rated on a scale from zero to one hundred. Under the TSI scale, bodies of water may be defined as:
oligotrophic (TSI 0–40, having the least amount of biological productivity, “good” water quality); mesoeutrophic (TSI 40–60, having a moderate level of biological activity, “fair” water quality); or eutrophic to hypereutrophic (TSI 60–100, having the highest amount of biological activity, “poor” water quality)
