Phosphates
Phosphate is one of the most important elements for growth of the plants and animals in the lake ecosystem. The presence of phosphate is often scarce in the well-oxygenated lakes, and low levels of phosphates limit the production of fresh water.
Levels:
0.005-0.05 ppm: typical of undistributed forest streams
<0.05ppm: suitable for human consumption
0.05-0.1ppm: may increase aquatic plant growth
>0.1ppm: likely to cause algal blossom
1.0ppm: approximately ideal upper limit for wastewater treatment plant effluent.
THE HEALTHIEST RIVER BASED ON PHOSPHATE RESULTS IS: OHIO RIVER