Oconee County experienced two major spills in the last nine months on its major force main sewer line servicing the county’s commercial hub due to problems during installation of the pipe joints or with the pipe itself, county leaders now believe.
The two breaks occurred about 100 yards apart at joints on the line, which runs along an unnamed tributary to McNutt Creek that separates Tanglebrook subdivision and the Pinewood Estates South mobile home park.
As a result of the breaks, up to 34,713 gallons of sewage on Feb. 13 of this year and 20,332 gallons on June 1 of last year spilled into the tributary just south of where it flows under Tanglebrook Drive at the entrance to Tanglebrook subdivision.
The untreated sewage then flowed into McNutt Creek, which feeds the Middle Oconee River.
County Administrator Justin Kirouac said the county is performing surge analysis and conducting spot checks on the integrity of the PVC pipe, which is seven years old.
The county also is getting in touch with the manufacturer of the pipe to determine if there have been any issues with the particular batch that was used on the 12 inch force main line where the breaks occurred.
The county has now filed its reports with the Georgia Environmental Protection Division (EPD) providing details of the Feb. 13 spill.
Suspected Cause Of Failures
Kirouac, in an email message shortly after the Feb. 13 spill, said both pipe failures began with splits in the bells where one end of the pipe is inserted into another.
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| Broken Pipe Feb. 13, 2025, Spill |
“Right now, we believe both failures are from over-belling the pipe ends upon installation,” Kirouac said.
When the pipe is inserted into the connecting bell beyond what is recommended by the manufacturer, this is called “over-belling.” Over-belling can cause stress on the receiving pipe.
“Both failures began with splits in the bells, which is usually an indicator of over-belling,” Kirouac said. “The one in June wasn't as large but appeared to be the same type of failure.”
“This recent one started the same way and creeped down the side of the pipe,” he said.
Adam Layfield, Director of the Water Resources Department, provided a picture of the pipe from the Feb. 13 spill, showing a break at the bell running down the pipe.
Layfield said the installation was done by the county’s on-call contractor.
In an update of that exchange after the second spill, Layfield said on Feb. 25 that “My staff is still trying to figure out if this was a faulty batch of pipe, but we haven't found anything yet that would suggest that. Presently, we believe it's an over-belling issue.”
The type of PVC pipe is called C900, he said.
EPD Reports February
According to the report Oconee County filed with the Georgia EPD, the Feb. 13 spill occurred at 7 p.m., and containment was at 7:30 p.m.
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| Upstream From EPD Report 2/13/2025, Spill |
Calculation of the volume of the spill is based on lift station run times and flow amounts per minute.
Layfield, who completed the initial report on Feb. 14, told the EPD that “The flow was stopped immediately once personnel was on site. Personnel replaced the broken pipe area of the force main and flow was restored once the repair was completed.”
Jenanne White of Oconee County Water Resources Department had notified the EPD of the spill via email at 8:46 a.m. on Feb. 14.
Stream monitoring on the day of the spill showed that Disolved Oxygen (DO) registered 9.6 at 50 feet above the spill to 8.19 at 50 feet below, and that Fecal Coliform (FCOLI) was 130 above the spill and 6,320 below.
A higher DO score is a sign of a healthier stream.
Layfield said on Feb. 25 that a citizen reported the Feb. 13 spill, as had been the case in June of 2024.
EPD Report June
The June 1, 2024, spill occurred at 10:19 p.m., with containment at 1:30 a.m. on June 2, according to the report filed with the Georgia EPD on June 3.
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| Point Of Entry From EPD Report 2/13/2025, Spill |
The calculation of 20,342 gallons of discharge was based on pump station run times, the report stated.
The cause of the spill was labeled as a “PVC Split.”
According to the report, the county “Turned off Lift Station. Cut out broken pipe and completed repair on C900 PVC.”
DO dropped from 6.72 at 50 feet above the break to 5.91 at 50 feet below on what was labeled Day 1 (June 3), and FCOLI was 1,940 above the spill and 5,330 below.
Sampling for Week 4 (9/23/2024) showed DO was 7.25 above the site of the June 1 spill and 7.48 below, and FCOLI was 1,330 both above and below the site of the spill.
Sewer Line Importance
The sewer line that runs along the tributary that separates Tanglebrook subdivision and the Pinewood Estates South mobile home park is a major part of the county’s sewer system.
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| Downstream From EPD Report 2/13/2025, Spill |
Sewage is pumped through that line from the large pump station between Parkway Boulevard and McNutt Creek just west of the bridge carrying Epps Bridge Parkway across McNutt Creek.
McNutt Creek forms much of the northern border of Oconee County with Clarke County, and a gravity feed sewer line runs along McNutt Creek from that pump station nearly to Bogart.
That sewer line along McNutt Creek is the collector for sewage from the county’s commercial hub along Epps Bridge Road, the Oconee Connector, and Virgil Langford Road.
Sewage from that pump station at Parkway Boulevard and Epps Bridge Parkway moves through pipe up the unnamed tributary of McNutt Creek to another pump station behind the shopping center where Trader Joe’s is located.
From that station, sewage is pumped under SR Loop 10 to a line running along Daniells Bridge Road and Experiment Station Road to Calls Creek and ultimately to the county’s treatment plant on Calls Creek on the north side of Watkinsville.
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