Calling Tuesday's 137-million-gallon sewage leak into the Tennessee River "a tragedy," Mayor Ron Littlefield said Wednesday the city will be installing a backup generator at the Moccasin Bend Wastewater Treatment Plant to try to make sure it doesn't happen again.
City crews also plan to resod Coolidge Park to remove contaminated grass and dirt on the city's signature North Shore riverbank.
"We'll leave it clean," the mayor said. "We all agree that this was a wakeup call, and we want to make sure that it doesn't happen again without having onsite backup power generation."
A faulty piece of insulation caused one of the main power lines inside the plant to short out Tuesday morning. The crippling collapse spread down three major power poles and "fried the wiring," shutting down the plant's treatment pumps, said Jerry Stewart, the city's Waste Resources Division director.
Other details about the spill and how to prevent future ones are being determined, he said.
"Basically, we'll have a sit-down and look at how we might improve our inspections, but I don't know if we could have stopped this," Mr. Stewart said. "Even if we were doing more frequent inspections, it's a random thing that I don't think anybody thought we'd have."
After the breakdown Tuesday, two rented generators arrived from Knoxville by 8:30 p.m. and cranked up two pumps. All electricity was functioning Wednesday after 18 hours of sewage leaks into the Tennessee River, Mr. Stewart said.
City of Chattanooga spokesman Richard Beeland said officials do not know the accumulated cost for two backup generators, Tuesday's contracted labor and various projects needed to purify the three affected areas. He said the city should have an estimate early next week.
SAFETY ISSUES
Tennessee American Water Co. officials have said the spills occurred downstream of the city's drinking water intakes, but they will monitor for any need to increase treatment.
State officials have notified officials in South Pittsburg, Tenn., which is downstream of the spill, to be on the watch for possible contamination.
"South Pittsburg collected additional E. coli samples at their intake, but do not expect any increased number due to the very high flows in the Tennessee River," said Tisha Calabrese-Benton, spokeswoman for the Tennessee Department of Environment and Conservation.
With a buildup of stormwater from Sunday's rains, the Tennessee Valley Authority released a total of 80 billion gallons into the river on Tuesday, which should nullify any hazardous effects that the organic sewage matter might have on the region's drinking water supply, according to Mr. Stewart.
But he had words of advice for those considering a river excursion in the next few days.
"Anybody that's smart wouldn't be out there right now," he said.
Citing weather issues and the difficulty of acquiring fresh sod in winter, Chattanooga Parks and Recreation supervisor Don Lewis said it could take "several weeks" to repair the contaminated area underneath the Market Street Bridge at Coolidge Park.
"Typically, sites which have overflows are vacuumed and have powdered lime applied to the area to kill the bacteria," said Ms. Calabrese-Benton. "The Tennessee River is at extremely high levels right now, so areas of the Riverwalk are underwater."
Riverfront boat ramps were closed to all boats Wednesday because of the river levels. The city also posted signs where overflows have occurred along the Tennessee Riverwalk.
Ms. Calabrese-Benton said regulators will not cite Moccasin Bend for Tuesday's waste spill.
INFRASTRUCTURE CONCERNS
Mr. Stewart said Tuesday's spill was the largest in Moccasin Bend's 49-year history. He said the plant recently received an equipment upgrade, but the next one is scheduled for 2020 or 2025. Many sewage lines are more than 100 years old, he said.
"They'll probably be replacing the lining over the next several years," he said. "We've been working very diligently over the past five years (to achieve) what the (Environmental Protection Agency) and TDEC call CMOM: capacity, management, operation and maintenance of the sewer system."
About 25 percent of the city's sewage system is cleaned every year, Mr. Stewart said.
BY THE NUMBERS
* 137 million gallons of untreated wastewater into Tennessee River
* 18 hours of unmitigated sewage flow
* 80 billion gallons of water run Tuesday by TVA
* Sewage made up 0.17 percent of Tuesday's total river flow
Source: City of Chattanooga