Leak plugged at Wichita sewage treatment plant, slowing river contamination
01/14/2014 11:55 AM
08/06/2014 1:30 AM
The leaky valve at Wichita’s main sewage treatment plant has been temporarily plugged, apparently at least slowing the the flow of contaminated water into the Arkansas River that resulted in state officials issuing a public health advisory.
Kansas Department of Health and Environment inspected the repair Tuesday and found the river’s water quality was improving in the vicinity of the valve near 71st Street South, agency spokeswoman Miranda Steele said.
But she noted that inspectors can’t determine if the leak is “completely sealed off” because the valve is submerged in the river.
City officials will continue doing daily testing for at least the next two weeks to determine whether the temporary fix is working, said Joe Pajor, the city’s assistant director of public works and utilities.
Meanwhile, the health advisory remains in effect for the river from the Lincoln Street Bridge to the Oklahoma border. KDHE has said people and animals shouldn’t have any contact with the river between those locations until further notice.
The advisory could be lifted as early as later this week if water quality improves enough, Steele said.
She noted that testing of water downstream near Winfield showed there was no threat.
The leak also resulted in a fish kill, although the size of the kill hasn’t been determined, said Doug Nygren, an official with the Kansas Department of Wildlife, Parks and Tourism.
The city is working toward a permanent solution, which is to to cut off the line served by the valve.
“The line served by the valve is no longer required because it was protection for equipment that has changed over the years at the plant,” Pajor said.
Work on a design to permanently seal off the 72-inch pipe has already begun, he added. But in the meantime, if the current temporary repair isn’t working, he said an alternative temporary plug will be put in place.
City officials are still trying to determine how much contaminated water was dumped into the river from the plant on 57th Street South, just east of Hydraulic and on the river bank. How long the valve has been leaking is also unknown, Pajor said.
The leak was discovered last Friday during KDHE’s routine quarterly testing of the river’s water quality at the East 83rd Street Bridge on the west side of Derby, Steele said.
Additional tests were made at other sites on the river that confirmed there were high levels of E. coli bacteria.
City workers found the leak was coming from the valve on Saturday and put in a temporary plug Monday.
Although the plant is several miles downstream from the Lincoln Street Bridge, Steele said the warning included the bridge for two reasons.
“The bridge is a landmark and is easily identifiable for residents,” she said. “People wouldn’t necessarily know where the treatment plant is.”
Gates on a recently installed dam at the reconstructed bridge were raised last Wednesday to increase the water level for the Wichita River Festival, which starts its nine-day run on Friday. The festival is held along the river north of the bridge.
But Steele said there is a chance that some of the stagnant water around the bridge hadn’t moved downstream.
“It’s best to be safe, even though our monitors were downstream from the Riverfest area and the Lincoln Street Bridge,” she said.
The city doesn’t anticipate any problem from the leak for Riverfest activities, Pajor said, since they are all upstream from the detected high levels of bacteria.
But as in the past years during Riverfest, Pajor said the city will monitor the water quality near the Riverfest.
River caution flags will be posted during the festival. Blue flags indicate no restrictions; green flags mean boating is allowed but no water should be ingested; and orange flags restrict any contact with the river.