May Water Quality Monitoring Results

On May 19 - 21 we collected water quality samples at our usual river and stream sites (list, map). Of the nine sites we sampled five had bacteria results that were above the state standard. E coli. is a bacteria that can indicate the presence of pathogens, often related to contaminated stormwater or untreated wastewater, that may cause human health risks. The standard for contact recreation (swmimming, wading, paddling) is 349 / 100ml.

May WQ Results
Sample Site E. coli Result Date Sampled
Congaree River 13.4 5/18/16
Saluda at I-20 29.2 5/18/16
Saluda at Saluda Shoals 547.5 5/18/16
Broad River 866.4 5/20/16
Gills Creek 293.4 5/19/16
Rocky Branch 1413.6 5/19/16
Smith Branch 1413.6 5/19/16
Stoops Creek 41 5/18/16
12 Mile Creek 686.7 5/18/16

The Midlands received trace amounts of rain on the 18th with heavier rain beginning the morning of the 19th, while we were conducting our sampling. The high bacteria numbers for Rocky Branch and Smith Branch were likely caused by stormwater runoff. Rain picks up pollutants from roads, parking lots, lawns and parks and washes them into our streams and river. The concentrations of pollutants, including bacteria, is usually highest at the beginning of a rain event, in what is called the "first flush." 

The Saluda at Saluda Shoals sample site is located just below the discharge for the Carolina Water Service Friarsgate Wastewater Treatment Plant.  It is also between the boat ramp and canoe/kayak launch at the park.  The high bacteria numbers here were likely related to an issue at the wastewater plant. DHEC staff indicated there was a problem at the plant but it was unclear if that was the same issue that caused the exceedence at the discharge, or if it has been resolved.

The results from the Broad River and 12 Mile Creek sites may be a combination of stormwater and wastewater issues.