Between Nov. 28 and Nov. 30, the Valdosta area received approximately 4 inches of rain — half an inch Friday, 3 inches Saturday, and another half an inch Sunday. Inflow and infiltration from the heavy rain entered the sanitary sewer system, causing high flows at both treatment plants.
There were two reportable separate sewage release incidents from the Withlacoochee Publicly Owned Treatment Works and associated sewer conveyance system:
The first spill resulted from the exceptionally high flows Saturday, Nov. 29, at the Withlacoochee Water Pollution Control Plant. The high flow rate resulted in the washout of secondary clarifier blankets, resulting in the bypass of the final filters, causing high total suspended solids in the effluent of the facility. The effluent total suspended solids result for Nov. 29 was over 150 percent of the weekly average, which constitutes a “major spill” as defined in the facility’s NPDES permit. The estimated volume of this spill was approximately 6.5 million gallons. The Withlacoochee Treatment Plant staff has started the required upstream/downstream sampling of the receiving stream, the Withlacoochee River.
The second spill was the surcharge from an interceptor line manhole upstream of the Withlacoochee facility, resulting in a discharge of approximately 135,000 gallons of raw sewage onto the ground surrounding the manhole. It is unknown how much of the discharge may have reached the Withlacoochee River. The upstream/downstream monitoring for the plant’s major spill event will cover the sampling response for this spill as well.
For more information, contact the Environmental Manager John Waite at (229) 259-3592.
