Charleston Lake Water Testing Program
On hold for 2020 season due to COVID
Water clarity is recorded at each of the seven sample sites on the lake on six dates between May 1st and the end of October. There is an extensive database on Charleston Lake for this parameter extending back into the mid- 1970's. Since the year 2000, the seven basins of Charleston Lake have been monitored for water clarity phosphorus and calcium concentrations and periodically surface to bottom water column oxygen and temperature values. These are reported on annually.
For those who may not be aware, when water clarity recordings are made, the on-site weather and water conditions are also recorded due to the influence that these have on light penetration in the water column. Secchi disc depths are dependent on the incident light striking the lake surface travelling down to the Secchi disc and then reflecting back up through the water column to the surface. Water clarity values should ideally be recorded only from mid-morning until mid-afternoon when the sun is overhead and always recorded from the shaded side of the boat. Along with the Secchi depth, the data and time, the estimated percent of cloud cover, whether it is sunny or dull, surface water conditions, including wave height and / or ripples, estimated wind strength and the water color (is it greenish or brown colored) are all recorded. Having this field of information assists with the interpretation of the clarity data.