Between Thursday and Monday, more than 1.6 million gallons of untreated sewage escaped the city-owned Decatur Utilities wastewater system, according to documents the utility filed Tuesday with the Alabama Department of Environmental Management.
Many of the 16 overflows originated in Councilman Billy Jackson’s district, and most of the untreated sewage flowed through Dry Branch Creek in his district as it made its way to Wheeler Reservoir.
“It’s time for the director of Decatur Utilities to come before the council and to give an explanation of what’s going on and how we’re going to fix the problem. This is not acceptable,” Jackson said Tuesday. “If Decatur Utilities can’t do it, then I think it’s time to pursue other options and see what we can legally do to take care of the problem.”
In the disclosures to ADEM, DU attributed the 1,680,021 gallons of sanitary sewer overflows to "inflow and infiltration from 3.28 inches of rainfall from 1-2-2020 through 1-4-2020."
Inflow and infiltration refers to water entering sewer mains, usually during heavy rains, causing the sewer system's capacity to be overwhelmed.
"The wastewater collection system is overwhelmed by heavy rainfall which infiltrates the system through cracks, holes, loose joints, broken pipes, leaking manholes or other pipe defects due to system age. This is especially prevalent in older clay pipe installed in years past," said DU spokesman Joe Holmes in a press release he sent out Monday, which also noted that the infiltration dilutes the raw sewage.
The largest reported sewer overflows from Thursday through Monday:
• 518,550 gallons from a manhole near 2812 Central Parkway S.W.;
• 195,195 gallons from a manhole near 1108 Sixth Ave. S.W.;
• 160,746 gallons from a manhole at 1302 Brindwood Lane S.E.;
• 136,920 gallons from a manhole near 1111 Central Parkway S.W.;
• 130,200 gallons from a manhole near 602 Eighth St. S.W.;
• 129,333 gallons from manholes near 2812 Wimberly Drive S.W.;
• 102,270 gallons from a manhole near 1301 Plaza St. S.E.; and
• 99,750 gallons from a manhole near 1606 Summerlane S.E.
Fifteen of the overflows began Thursday through Saturday. One on Monday, releasing 9,660 gallons of sewage at a manhole near 619 Memorial Drive S.W., was attributed by DU to a blockage in the sewer main.
The receiving creek for most of the Southeast Decatur sewer overflows was reported as Flint Creek.
DU's reports to ADEM identified Bakers Creek as receiving most of the Southwest Decatur overflows, but when asked Tuesday how that was possible, Holmes said it was a mistake.
"All overflows along Central Parkway ultimately enter Dry (Branch) Creek. This is a reporting error that is currently being corrected," he said in an email.
Bakers Creek is in an industrial area off State Docks Road, next to 3M Co.
Dry Branch Creek flows through residential areas in Northwest Decatur, is adjacent to Leon Sheffield Magnet School, and enters Wheeler Reservoir near Ingalls Harbor.
In his statement Monday, before DU had reported the volume of the overflows to ADEM, Holmes said the utility is working on the issue.
"The DU wastewater collection system is currently undergoing a new sewer system engineering study which will evaluate improvements in those areas where previous investment has been made, as well as identify basins that should be prioritized for future rehabilitation projects beginning in 2020," he wrote.
Asked about the study Tuesday, Holmes said, "The study is being conducted by Barge Design Solutions at a cost of $425,000. It was approved at DU’s September 2019 board meeting."
Mayor Tab Bowling said he expects to meet with DU officials soon to “discuss options to expedite efforts to improve our sanitary sewer collection system piping and manholes.”
“They know that I need to meet with them. They have a request from me to sit down and meet,” he said Tuesday. “Nothing is scheduled.”
While DU operations are largely independent of city government, the City Council has considerable authority over it. The City Council appoints its board members, must approve DU expenditures exceeding $100,000, and must approve any rate increases.
Bowling noted that bond rates are extremely low right now, which he said might be a reason to borrow money and accelerate improvements to the sewer system.
“But they’re the experts, and I need to talk to them and listen to them,” he said.
Holmes said DU has invested more than $60 million in projects designed to reduce and eliminate SSOs in its wastewater collection system over the last 10 years.
In the ADEM disclosures filed Tuesday, most of the overflow reports included a description of the remedial efforts DU is taking: "The affected area was marked with a sign, cleaned via pressure washing, and disinfected by DU field personnel. DU is continuing rehabilitation efforts to the sewer collection system to eliminate inflow and infiltration and to prevent future overflows."
From Dec. 21 to Dec. 23, 810,075 gallons of untreated sewage escaped the DU sewer system during heavy rains.
According to the U.S. Environmental Protection Agency, sewer overflows contain bacteria, viruses, parasitic organisms, intestinal worms and molds. They cause health problems ranging in severity from stomach cramps and diarrhea to life-threatening ailments such as cholera, dysentery, infectious hepatitis and severe gastroenteritis, according to an EPA advisory.