Updated April 29, 7:30 p.m.
With the Mississippi River below 33 feet, MSD says it no longer has to use the pumps, and the flow of untreated wastewater into the river has stopped. The temporary pumps will remain in place.
Updated April 29, 4 p.m.
MSD officials say that with the Mississippi River dropping, the flow of untreated sewage has slowed to 16 million gallons a day. Crews continue to work on installing two temporary pumps to replace the ones that failed. The cause of the failure is still under investigation.
Our earlier story:
The failure of two pumps at the Bissell Point water treatment plant on Sunday is causing the release of 105 million gallons of untreated wastewater into the flooded Mississippi River per day.
The pumps at the north city plant, which is owned by the Metropolitan St. Louis Sewer District plant are only used when the river is flooded. Altogether, they can handle about 250 million gallons of wastewater a day - about the amount running through the plant right now. MSD spokesman Lance LeComb says the one remaining pump plus some temporary equipment has dropped that capacity to about 145 million gallons a day.
"We don't know what went wrong yet," LeComb said. "They were just rebuilt two years ago, they went through their testing when they were brought back online. Because of the drought last year, they weren’t used much at all, so it’s very disappointing to say the least, somewhat infuriating, that we’re in this situation."
LeComb says the agency reported the spill to the Missouri Department of Natural Resources as required, but says the risk to public health is low.
"Given the volume of water that's going down the Missisippi right now, almost 400 billion gallons a day, that wastewater dilutes very quickly," he said.
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