One of the primary indicators of water quality is pH. Stream and lake pH depends on local ecology, the presence of inorganic and organic acids, and anthropogenic (man made) influences. Most aquatic organisms can withstand a pH as low as 6, but prefer a range between 7 and 8.5. pH values harmful to aquatic life use are the extremes-- below 5 or above 9.
Conductivity is a measurement used to determine the minerals content of water, which is commonly called total dissolved solids. Elevated dissolved solids can cause "mineral tastes" in drinking water. Corrosion or encrustation of metallic surfaces by waters high in dissolved solids causes problems with industrial equipment and boilers as well as domestic plumbing, hot water heaters, toilet flushing mechanisms, faucets, and washing machines and dishwashers. Agricultural uses of water for livestock watering are limited by excessive dissolved solids and high dissolved solids can be a problem in water used for irrigation.
Monitoring Stations and Frequency
Attached is a chart that shows the DEQ monitoring stations and the LVLA monitoring stations. Below is a list the LVLA monitoring stations and the rationale for choosing them. These monitoring stations were discussed with DEQ and DEQ agrees that they are good locations to monitor.
Station 1 is at Toler’s Bridge (near mile marker 12). This location is downstream of the Pigg River and will provide data on bacteria from the Pigg after it has mixed with water coming out of Smith Mountain Lake.
Station 2 is near mile marker 9 and will provide data on bacteria dilution downstream of station 1.
Station 3 is in the cove near Tri-County Marina. This location will provide data on bacteria near the swimming beach. It may also determine if there are any bacteria entering the water from Terrapin Creek or the homes around the cove.
Station 4 is near mile marker 3. This station will provide a data point upstream of the confluence with Old Woman's Creek (OWC).
Station 5 is near Pit Stop Marina and provides data at the confluence of Old Woman's Creek with lake.
Station 6 is north of Goat Island. It provides data on bacteria dilution as the water from OWC combines with the main river flow.
Station 7 is near mile marker 1. It provides another data point on bacteria dilution downstream of confluence with OWC and provides an indication of bacteria levels at the state park near the dam.
Latitude and longitude has been determined for each station and DEQ assigned DEQ river-mile station IDs.
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