When a torrential rainstorm in the middle of September caused major flooding in downtown Brunswick and the Sterling area, it also inundated the public sewer system.

Higher rainfall typically translates into more stress on the Brunswick-Glynn County Joint Water and Sewer Commission’s three wastewater treatment plants, and not by design.

Stormwater runoff and groundwater tend to get into the sewer system via breaks in underground pipes and manholes.

The JWSC has invested hundreds of thousands of dollars over the last few years to patch the system and has made some headway, but not enough to keep out the nine-plus inches of rain that fell in mid-September.

“The last month has been a little bit of an outlier in the last two years,” JWSC Executive Director Andrew Burroughs told utility commissioners at a Wednesday committee meeting. “We had nine inches over one month on the island. We had that in one day on the mainland.”

The Academy Creek Wastewater Treatment Plant in Brunswick saw the worst of it, which caused the plant to briefly fall short of standards set in the U.S. Clean Water Act, according to documents provided by the JWSC. Sewage treatment plants on St. Simons Island and in the Southport area did not face the same problems.

That one day threw off the entire month’s sewage treatment reports, Burroughs said.

The incident wasn’t enough to upset the state Environmental Protection Division, however. Burroughs said the utility submitted plans preventing a similar event from occurring in the future and expects no punitive action from the EPD.

The Academy Creek plant is not usually operating at full capacity, Burroughs said.

A typical month would require only 50 percent or so. When not in use, parts of the facility are cycled in and out of active status to save resources.

Burroughs said the JWSC is writing procedures to quickly activate more of the treatment plant when needed.

On the plus side, Burroughs said such extreme weather has the side effect of showing which parts of the sewer system need the most attention.

Utility Commissioner Donald Elliot asked whether the JWSC should take such heavy rains into account when planning for the future. A Glynn County grand jury appointed him to the commission when the state was in a drought, and many decisions may have been based on the weather conditions at the time.

“When I started, we weren’t getting any rain,” Elliot said.

Commission Chairman Ben Turnipseed said long-term decisions shouldn’t be made based on a single day’s rainfall but rather on average annual rainfall.

Utility commissioners also recommended the full commission move ahead with a $242,000 contract with Bio-Nomic Services to repair 73 manholes throughout the county.

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