State environmental regulators have slapped the city of Columbia with a clean water violation over a raw sewage spill into Hinkson Creek.
In a report issued Monday, the Missouri Department of Natural Resources found the city liable for two violations of the Missouri Clean Water Law. The violations involve a sewage overflow behind the Wal-Mart Supercenter on Conley Road.
The state did not levy any fines for the two violations, but instead ordered the city to “implement a routine maintenance schedule of grease traps … connected to the city’s (sewer) system.”
City and state inspectors identified a Wal-Mart kitchen, a McDonald’s within the super center and a third Wal-Mart food production area as the culprits of the spill.
“The grease was from the food production … and caused (the) overflow,” said Dennie Pendergrass, chief operations engineer with the city’s Public Works Department.
Pendergrass received the report Tuesday and said he was still reviewing its contents.
Hinkson Creek was added to the federal impaired waters list in 1998 due to a history of fish kills. The DNR continues to work on a larger study of Hinkson Creek’s water quality, an agency spokesman said.
Pendergrass said the city investigated the spill soon after it was reported in early August and took all necessary steps to clean it up, including pumping the grease back into a sanitary sewer.
The city must provide the DNR with detailed information by Sept. 30 about its plans to reduce accumulation of grease in sanitary sewer mains to prevent similar mishaps.
The state investigation shows the overflow caused odor, sediment deposits and a change in the color of a portion of the creek.
The spill also caused an increase of E. coli bacteria. However, that was not listed as a violation because the creek is not considered a suitable place to swim.
No dead or distressed fish were observed.
But even though the creek is not listed for whole-body contact use, a DNR inspector observed children wading 100 to 200 yards downstream from the sewage, said Kerry Cordray, a DNR spokesman.
“This is a stream where kids are playing,” he said.
Cordray said the city responded promptly to the spill, which was reported by a golfer at Columbia Country Club.
“The combination of some citizen awareness, prompt reporting and a swift investigation following the report resulted in a limited damage to the stream than might have happened,” he said. “The situation could have been a lot worse.”