More than a week after 200,000 gallons of sewage spilled into a South Hall creek, fecal coliform levels in the water have lowered from a height of 5,700 counts per 100 milliliters.
That number made the water in Sherwood Creek unsafe for direct contact, according to Marzieh Shahbazaz, a program manager for municipal compliance with the Georgia Environmental Protection Division.
Counts should not be above 4,000 on any given day for water used for recreation, according to state regulations.
But even that high number is relatively low for a sewage spill of this size, Shahbazaz said. She said heavy rains could have diluted the spill.
“I have seen much higher numbers downstream on the first day (after a spill), but most rivers, because of dilution, they recover,” Shahbazaz said.
Repairs on the broken pipe at Sherwood Creek are expected to be complete later this week, according to Ken Rearden, the county’s public works director.
The leak was discovered on Nov. 17. The pipe broke when it shifted due to erosion from heavy rains that week, when the Reunion subdivision received about 4 to 5 inches of rain.
Water in the creek has been tested at two sites, one 50 yards upstream from the spill site and the other 1,000 yards downstream.
On the morning of Nov. 18, the water upstream had a fecal coliform count of 180 parts per 100 milliliters, according to testing data from the county. That number downstream was much higher, at 5,700 parts per 100 milliliters.
The next day, on Nov. 19, the upstream count was 220, while the downstream count was 310, a number that Shahbazaz said is not especially high. Counts have been declining since then, and on Sunday morning, levels were at 119 upstream and 118 downstream.
Rearden said data from before the spill was not available because the county had not been required to test Sherwood Creek regularly.
According to state regulations, for water that is used for recreation such as fishing, fecal coliform levels should not exceed a geometric mean of 1,000 parts per 100 milliliters between at least four tests over a 30-day period between November and April, when water recreation activities are less likely to be occurring.
County officials reported the spill to the EPD when it was discovered. Sherwood Creek flows into the Oconee River and is not connected to Lake Lanier. Drinking water was unaffected.