More than 2 million gallons of sewage flowed into Bush River in the Edgewood area of Harford County during and following last week's torrential rainstorm, Aberdeen Proving Ground and Harford County officials said.
The largest of the releases involved about 1.8 million gallons of "partially-treated" sewage that entered King's Creek and Bush River from a U.S. Army wastewater treatment plant on the Edgewood Area of Aberdeen Proving Ground last Wednesday.
About 300,000 gallons of untreated sewage diluted with stormwater overflowed from Harford County's Bill Bass pumping station during an 11-hour period between 3 p.m. last Wednesday and 2 a.m. Thursday, according to a Harford County government spokesperson. The pumping station is on the Bush River shore at the end of Kennard Avenue in Edgewood.
APG – Edgewood overflow
According to a statement from the Army, the overflow from the APG treatment plant occurred after the plant's "primary tanks" overflowed, as the Aberdeen Proving Ground area received 5.6 inches of rain in 24 hours.
The overflow got past the secondary clarifier tanks of the plant, according to the statement. Secondary clarifiers are typically used to separate sewage sludge from the treated wastewater.
The plant has the capacity to treat 3 million gallons per day.
Workers applied lime to treat the APG spill and posted signs barring people from fishing, crabbing, catching shellfish or swimming in the creek and river "until further notice," according to the Army statement.
"We continue to monitor the area, continue to take samples and continue to test the area," APG spokesman Kelly Luster said.
Luster said via e-mail Monday that water samples have been sent for analysis, and the results should be available later this week. Officials expect the majority of the spill will be made up of rainwater, but they are waiting for lab results.
He also noted no fish kills had been reported "at this point."
The Harford County Health Department is "satisfied" APG officials have met their obligations for reporting and assessing the spill, plus making the proper notifications and placing the proper public signage, health department spokesman William Wiseman said Friday.
"The event has occurred and in resolving itself in the normal course of events, will eventually dissipate," Wiseman wrote in an email. "Given the volume of rainfall, there was considerable dilution of spillage."
Rainfall amounts reported for Harford County from the night of Tuesday, April 29, through early Thursday morning, May 1, ranged from 5 to 9 inches.
Wiseman also stated that "there is no evidence of which HCHD is aware" regarding harmful impacts to fish or other forms of aquatic life in the river.
The overflow from the Bill Bass Pumping Station was a result of "the overwhelming flow that was caused by the infiltration and inflow of stormwater into the sanitary sewer system," Harford County government spokeswoman Sherrie Johnson said late Friday afternoon.
"During the storm, the flow to the station was more than four times the normal peak flow," Johnson continued, adding: "The water that overflowed was highly diluted with rainwater."
Johnson also said about 200 gallons of sewage was released from a smaller pumping station on East Baker Avenue in the Long Bar Harbor area of Abingdon, also along Bush River, between 5 and 8:30 p.m. last Wednesday.
"Like Bill Bass, this station [Baker Avenue] was severely affected by excessive amounts of stormwater, and the peak flow was about 13 times the normal rate of flow of 30,000 gallons per day," she wrote.
Both spills were reported to the Maryland Department of the Environment and the Harford County Health Department, according to Johnson, who said warning signs have been posted advising the public of the overflow and to avoid contact with the water in the immediate vicinity of both facilities.