Water Quality Statement

[Guest]

Hello lake Avalon Folks,

Last year we received approval from the state on a nutrient management plan for the lakes that allows us to augment the nutrients in the lake, only when the lake needs it. The idea is to promote plankton growth in the water to support a healthy lake aquatic food web resulting in fish populations robust enough to support good angling. This is likened to what used to be called “lake fertilization”. The difference now is that we can manage the nutrient levels in the lake only enough that we do not have a negative impact on water quality as was occasional a problem in the past. Now we apply nutrients to a given lake based on water monitoring criteria according to the state approved nutrient management plan. We only apply enough nutrients to the lake to reach our target, desired range of water clarity and no more. And we cannot reapply any nutrients until the lake clears beyond the target range and trigger level in the plan.

Our target range for water clarity is 1 to 2 meters or 3 to 6 feet as measured by a device called a Secchi Disk clarity. When the clarity is more than 2.5 meters (about 8 feet), we can apply nutrients to the lake to try to get the plankton to “bloom” which decreases the water clarity and we try to get the clarity to the target range. We will reapply nutrients only as needed and only as the plan allows to keep the lake in the desired range of water clarity. As an example, our nutrient management plan was approved in March 2011, but only two lakes last year reached the clarity criteria allowing us to augment nutrients – Lakes Ann and Lomond. Windsor had perfect water clarity all last year as it stayed in the 1 to 2 meter (3 to 6 feet) Secchi water clarity range all during the warm season on its own, as did Avalon. Therefore, we never had to augment nutrients in Windsor or Avalon last year. This year we have augmented nutrients in Lomond, Windsor, Ann, and Avalon because we are having a dry year and little nutrients are entering the lakes from rain events. Lakes Brittany, Norwood, and Rayburn were not eligible as they are part of a special study.

A few weeks ago we applied about 1 lb per acre of phosphorus along with about .1 pound per acre of nitrogen to Avalon and got little response. Today we will apply about 2 pounds per acre of the same mix. We will monitor the resulting plankton bloom as dictated in state approved nutrient management plan, to see if we achieve the desired results. It is important to note that if we let the water stay very clear with little plankton in the water, substrate (filamentous) algae grows from the lake-bed due to the increased amount of sunlight reaching deeper in the water. Substrate algae is the slimy green stuff that eventually grows up to the surface and floats around in mats. When that occurs we use aquatic herbicides to try to kill it which is also undesired. The lake is in a much healthier condition when we promote good plankton in the water, instead, which outcompetes, and shades the substrate algae, preventing it’s growth.

[Quillback]

I get those emails also, it's great to see they are keeping the lakes at an optimum nutrient level to promote a healthy environment for the fish.