Contributed by Beth Bauer, Board of Directors
Fighting Biology With Biology!
This was the message from John Tucci of Lake Savers when he spoke at the town hall meeting on Thursday, October 26 at the Community Center. He talked specifics but essentially said the we need to give our lake what it needs to be healthy. The challenge at Lake Heritage has been to do it fast.
The problem, as Tucci saw it, was that in 2015 our lake had very high phosphorus levels, oxygen was depleted below 10 feet, and the sediment on the bottom was 70% compost. All of this fed weeds, algae, and e coli bacteria. Our lake was dying.
Tucci readily admitted that 2016 was a big fail. Lake Savers got behind in the fight and never caught up. In September 2016, Tucci shared at that town hall meeting that the plan was to do whatever was necessary to make 2017 summer a good summer at the lake. Essentially that plan was to first, increase the biological treatment; second, use a peroxide based treatment; third, to use copper sulfate.
Why not continue to use copper sulfate? Research shows that while this kills algae, within 21 days the algae is back. In addition, with time, the blue-green algae becomes resistant. Copper sulfate is bad to people, bad for the lake, and good only for algae.
So, what did Lake Savers do in 2017 at the lake? They used a biological treatment with a minimal use of peroxide. There was no use of copper sulfate. Yes, there was some green algae in late April and early May, but by Memorial Day there was significant improvement in the lake. There were plans to bring in copper sulfate in late May, but improvement was so significant, that it was canceled. Again in late September, there was an algae bloom, but biological treatment was successful. The lake was great from Memorial Day through Labor Day. The key is to start earlier and go later.
Lake Savers used a bioblast treatment. This is a micro brew of beneficial bacteria strains. It consists of common soil and water organisms that are native to North America. It is certified organic and non GMO. There were 10 treatments in 2017 totaling in 200,000 gallons. Also, three additional diffusers were added to the deep end of the lake.
In addition to what Lake Savers did, the cleaning of the coves over the winter by the maintenance crew was a huge help. There are plans to continue this in the coves not done last winter. Also, the floating islands of water hyacinths planted by members of the Lake and Dam committee made a difference. These plants flourished and removed phosphorus from the lake. The plants have been taken out of the lake and destroyed.
The message according to Tucci was that is takes a community to turn a lake around.
We all know the lake looked great this past summer, but what did the data show? Testing done independently by Aquatic Engineering in 2017 showed that algae overall decreased. Microcystin levels were lower in the lake than what is allowable for drinking water. Water clarity and temperature increased. Total phosphorus is declining in the lake but is still the major issue to be attacked.
The next question according to Tucci is where to in 2018? The work done in 2017 was expensive. How do we avoid this in future years? Tucci recommends continuing to drive down phosphorus and work for a reduction in the water column. Do this through continued aeration and floating islands. He also spoke about the potential use of a phosphorus sponge technology that is in research currently. Lake Savers is working to commercialize this technology. In the meantime, we continue to fight biology with biology.
Webmaster’s Note : See John Tucci’s Presentation