Residents have noticed that more fish are dying in Fountain Lake. Fish being found lethargic and some washing ashore dead is not an uncommon occurrence during the hot summer months in most urban lakes. The most common cause of this situation is sudden oxygen depletion in the water caused by several natural factors.
On cloudy days, plants' photosynthesis does not produce as much oxygen. Other factors include high winds mixing deep water with surface water. When the water at the bottom, which has low oxygen concentrations, mixes with surface water, it reduces the overall pond oxygen supply very rapidly. This sudden oxygen depletion will often happen in 24 hours.
Chemicals in deep pond water, such as carbon dioxide, can further stress fish when high winds mix a pond. These issues are complicated at night when lake oxygen levels naturally decrease due to photosynthesis not occurring at night. The lake's oxygen levels drop nightly but usually not to an alarming level.
Algae Kill is another possibility. When large amounts of algae or other plant life in a lake occur and die rapidly, the oxygen levels of the entire body of water will also rapidly be reduced.
The Town has taken proactive steps to address the issue by partnering with a professional lake management company. This partnership involves regular testing of the lake's oxygen levels, algae, PH, and ammonia. The most common issue identified is sudden oxygen depletion. To counter this, the staff has been running the fountain throughout the day to increase the oxygen availability in the water for the fish.
Once the water test results are available, staff will do whatever is necessary to improve the lake's water quality.