Pollution fouled South Carolina’s coastal waters after Tropical Storm Irma with tests revealing spikes in fecal bacteria.
Testing conducted by the Charleston Waterkeeper after Irma found 13 of 15 sites had a concentration of fecal bacteria higher than considered safe for swimming. The worst was in the Folly River, at 18 times the level safe for swimming, according to waterkeeper Andrew Wunderley. Fecal bacteria is the only real pollution tested for in open estuary or river waters.
A blue heron flies over an oyster bed on the banks of the Folly River. Charleston Waterkeeper fecal testing after Irma found 13 of 15 sites had a concentration higher than considered safe for swimming. The worst was the Folly River. File/Staff
Officials say drinking water supplies weren’t affected, but water pollution testing has been criticized as too limited in a fast-developing region facing growth concerns.
The reported increase in fecal bacteria, which comes from human and animal waste, didn’t approach readings from Hurricane Harvey’s catastrophic deluge on Texas, where the fecal bacteria was recorded at 58 times more than the safe level in flood waters, according to reports in the Houston Chronicle.
But it was consistent with what is seen in the wake of major storms.
“We see high bacteria levels across all our testing sites after storm events like Irma, Matthew and (the) flood of October 2015,” Wunderley said. “That’s because floodwater flushes out septic tanks, causes sewer overflows and washes pet and animal waste right into the nearest creek or river.” The bacteria eventually subsides.
Charleston Water System and Santee Cooper utilities officials said that while there were spikes in turbidity — essentially dirtiness — in the drinking water supply, the spikes did not reach levels where the water couldn’t be treated by staff. The Santee Cooper treatment plant on Lake Moultrie saw turbidity spike to about twice its usual level, spokeswoman Nicole Aiello said.
Utilities use turbidity as an indicator of whether other pollutants might be present. It’s among about a dozen tests regularly done on intake or treated water.
The two utilities provide drinking water for most of the Charleston area.
“They did adjust (chemical treatments of chlorine compounds and minerals) … but the adjustments were within the normal checks and balances,” said Andy Fairey, the Charleston Water System chief operating officer.
Sewer treatment staff also made the same sort of adjustments as the rain flushed in more flow, he said.
No additional water monitoring was done by the state after the storm, said Tim Kelly, the S.C. Department of Health and Environmental Control media relations director.
For at-risk plots of land, the Environmental Protection Agency visited all of the 35 Superfund sites in South Carolina after Irma, including at least three in the Charleston area. But no samples were taken, he said.
“At this moment, the EPA hasn’t alerted us to anything warranting action,” Kelly said.
State monitoring of water quality has fallen off in recent years because of budget crimps even as efforts to maintain the more urban coastal estuaries for fishing or swimming aren’t stopping pollutants from continuing to foul the waters. The water quality in the Charleston Harbor has been deteriorating for years, according to researchers.
In outwash of the historic floods in 2015, sewage and other fecal waste showed up in the harbor. All 15 area sites tested by Charleston Waterkeeper were considered unsafe for swimming. The flood created wastewater treatment issues across the state, according to DHEC at the time.
“But it doesn’t take a hurricane or flood to pollute local waterways,” Wunderley said. “Average rainfall events pollute our local creeks and rivers on a regular basis. In fact, we see high bacteria levels after only a few inches of rain.”
Water quality was already poor at many of the sites before Irma because of rain, he said. Some of the highest bacteria counts of the year were found two weeks before the storm. Shem Creek testing then found levels at 24 times and 19 times above safe swimming levels.
“We need to make a serious commitment to improving our stormwater management so it mimics the natural relationship between the land and water,” Wunderley said. “We have to allow areas to flood and ‘un-flood’ by preserving wetlands and green space and allowing water to better infiltrate the ground in built-out areas.”
“We can’t tunnel, pump and drain our way of this problem,” he said.
