An engineer with the City of Jacksonville now estimates the raw sewage spill at 39,150 gallons.
In a statement from the city, Glenn Hargett wrote, "Jacksonville Police are now part of the investigation into tampering of a valve which allowed untreated wastewater to get into Mill Creek this weekend. A City engineer, working with known facts, has estimated the amount of wastewater that escaped from where the valve was on the line, to be 39,150 gallons."
It was Saturday morning when city workers found an air release valve disconnected from a pump line at the Henderson Drive Pump Station.
Hargett's statement added, "An engineer with the City used known flow and known operational time of the pumps to calculate how much flow could have escaped. That calculation was found to be 39,150 gallons. That figure is being reported to State officials as the potential maximum amount that could have been lost. Wastewater staff members believe the number to be about 15,000 gallons based on their experiences."
No fish kills or other biological problems have been reported from the contamination.
City crew members say Saturday morning they found an air release valve disconnected from a pump line. They say the valve was in place when it was checked late Friday and the pumping station was in normal working order during the routine inspection.
Officials say they think someone vandalized the line between 10:00 p.m.Friday and 2:00 a.m. Saturday. They say the discovery was made during a routine check about 9:00 a.m. Saturday and there was evidence untreated wastewater entered Mill Creek. Crews closed the line to stop the spray from the disconnected valve.
The City of Jacksonville said testing results late Monday indicated the effect of the spill resulted in no fish kills or other biological effects so far.
The City has consulted with the NC Division of Water Quality which has required monitoring at specific locations as part of the follow up to the incident and as part of the investigation which is ongoing.
Jacksonville officials have launched an investigation after a valve disconnected leading to a sewage spill over the weekend.
City officials say an air release valve became disconnected from a major line and allowed untreated wastewater to spray in the ground.
They say crews discovered the situation at the Mill Creek substation Saturday morning and took action to close the line and clean up the area.
The location where the spray hit is about 30 feet from Mill Creek. Deputy City Manager Ron Massey says they believe about 100 gallons spilled onto the ground.
City crews used a high-powered vacuum to clean up the spilled wastewater that was visible and treated the area to sanitize it. Sampling began upstream of the site and downstream in order to establish a baseline of the potential impact.
Sampling received Sunday indicated that the number of tested bacteria counts were about five times higher downstream than the tested location upstream.