Below are the recent lab sample results for microcystin. We take a sample collection from the beach swim area and a sample collection from George’s Fork. The lab begins running samples at the end of each week. We need to have our samples in by Thursday. We typically get our results back on Monday or Tuesday of the following week. For example, the sample results for the pull on the 20th came back on the 27th.
I had a call with an EPA partner last week to discuss advisory levels that are issued for recreational public waters. Our objective is to follow the same guidelines. They did make a change with the advisory limits for microcystin. 8 ug/L is now the magic number. When a sample comes back at 8 ug/L, or more, it is advised to post a sign stating that there should be no contact with water. The previous no-contact advisory level was at 20 ug/L.
6/17: 2.6 ug/L
6/20: 6.4 ug/L
6/17: 3.5 ug/L
6/20: 7.5 ug/L
As many know, we decided to treat the lake on 6/27. The June 20th results that came in during the day on the 27th confirmed that our decision to treat on the 27th was accurate timing. Unfortunately, we will not be able to obtain a post-treatment test result back until after the 4th of July weekend.
On 6/29, we observed all areas of the lake to evaluate the effectiveness of the 6/27 treatment. We were very pleased with the improvement of the water clarity and the reduction of the algae characteristics. Our historical data tells us that microcystin levels are at least cut in half after treatment. Based on observations of the water characteristics on 6/29 and historical data, we are confident that our treatment was very effective at knocking back the algae and the microcystin levels.
Please contact me, Mike Casimir, if you have any questions. I am satisfied with the condition of the lake going into the holiday weekend. As always, if you have doubts about going into the lake, don’t.
Lake Water Quality Committee