Lake Singletary Watershed Association
Dedicated to the Preservation and Protection of Lake Singletary and its Watershed
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Water Quality
Determining the Condition
Trophic State
Trophic state is a method to classify lakes and is an indicator of water quality. Common characteristics used are clarity, chlorophyll (a measure of algae present), and total phosphorus concentration.

Oligotrophic lakes have low nutrient content, and thus are very clear, produce few weeds, and do not support large fish populations.
Eutrophic lakes are rich in nutrients, are subject to frequent algae blooms, and support large plant and fish populations. Eutrophic lakes, however, may be subject to oxygen depletion resulting in fish kills.
Mesotrophic lakes lie between these two states. Lake Singletary is classified as mesotrophic.
The transition from oligotrophic to eutrophic is part of the natural aging process of a lake, but human activities accelerate this process. The introduction of nutrients from the watershed leads to algae blooms, oxygen depletion, and weed growth.

Nutrients are introduced by non-point source pollution. Rainfall and subsequent runoff carry nutrients and pollutants from the watershed into the lake. Effluents from shoreline septic systems are an important non-point source of nutrients. Soil erosion from construction sites also introduces nutrients. In addition, erosion contributes to sedimentation and turbidity, and can be harmful to fish and aquatic organisms.
Non-point source pollution is difficult to control, because nutrients are introduced at relatively small concentrations over large areas. Land-use management strategies in the watershed must be implemented to control this type of pollution.
Graphs and Charts
Historical Data/Trends