Just as recent storms revealed weaknesses in Northern California’s dams and levees, they also exposed problems with Sacramento-area wastewater systems that failed to contain sewage.
Record precipitation in the last two months created more pressure than some sewer lines and plants could handle. From Jan. 1 to March 2, more than 1 million gallons of wastewater spilled in the capital region, most into waterways, according to reports made by sewage districts to the State Water Resources Control Board.
While spills occurred in several communities, most were in areas served by the Sacramento Area Sewer District and the city of Placerville. Sacramento-area and Placerville officials say they are studying what must be done to prevent future spills.
The region’s largest spill sent an estimated 582,000 gallons of wastewater from a Placerville sewer main into Hangtown Creek on Feb. 20. Tests conducted by the city revealed E. coli at 85 times higher than acceptable levels in treated wastewater dumped into the creek. E. coli dropped to acceptable levels before the wastewater entered the American River, according to City Manager Cleve Morris.
In recent months, the city reported three other sewage spills into Hangtown Creek, totaling about 80,000 gallons.
A February storm led to a sewage backup at a Placerville social services agency for foster children. The waste forced Summitview Child & Family Services, located next to the sewer main, to close some of its offices.
“It was very disruptive in that I had to relocate clients and employees for their safety,” said Executive Director Anna Gleason, who added that the contaminated office space has to be repaired and cleaned before it can be used again.
The Placerville sewer spills could have put others at risk, as E. coli can sicken and even kill people who swim in or drink contaminated water. But that likely didn’t happen because people probably weren’t in the creek during the storms, said Wendy Wyels, environmental program manager at the Central Valley Regional Water Quality Control Board.
Water providers that draw from the American River say the Placerville spills had no impact on their drinking water. Wyels agreed that such contamination would be unlikely, in part because of dilution from the storms and the volume of water in the American River.
Still, Placerville, the Sacramento Area Sewer District and other agencies face the possibility of sanctions, she said. The Central Valley water board wants to wait until the winter rainy season ends before deciding what action to take, she said.
After a series of sewer spills in Folsom, the board in 2002 ordered the city to improve its sewers. One spill carried an estimated 700,000 gallons of sewage into the American River, which prompted the board’s biggest-ever fine, $700,000.
The city has made improvements, and no sewer spills were reported in Folsom during this year’s storms.
The recent spills in the Sacramento Area Sewer District were spread over a wide area and were smaller than Placerville’s. The district collects sewage from much of Sacramento County and sends it to the larger pipelines and treatment plant run by the Sacramento Regional County Sanitation District, which discharges into the Sacramento River near Freeport. The district had six spills of 10,000 gallons or more in the northern suburbs, and reported a total of more than 400,000 gallons in spills in January and February.
The district is examining spill data to determine what improvements, if any, are needed, said spokeswoman Nicole Coleman. In its reports for the biggest spills, the district said they were caused by a “storm surge that exceeded the designed capacity” of pump stations or collection systems.
“These were isolated in nature, not a systematic problem,” Coleman said. The district’s “system had enormous and unprecedented pressure placed upon it.”
Placerville City Manager Morris said his city’s sewage spills resulted from heavy storms and aging infrastructure. While the city upgraded its sewer treatment plant in 2007, many of the lines are 40 to 50 years old, he said.
The line running along Hangtown Creek carries sewage from homes and businesses to the city’s treatment plant. Holes in the line allowed a tremendous amount of water to get into the line, mixing with the sewage and coming out as a mixture of sewage and stormwater into the creek, he said.
The city said the biggest spill happened at the line’s location at 640 Placerville Drive. The line’s metal casing appeared to be rusted through to its plastic liner in many locations last week.
The line runs behind a commercial section of Placerville Drive. The spills sent wastewater into Hangtown Creek, out of the city to the northeast and into Weber Creek before entering the American River. E. coli levels reached their highest at Weber Creek and Lotus Road, several miles from the city, likely because of other storm runoff joining the spill, Morris said. The contaminated sections of the creeks are rural, without much nearby development.
Morris said the city will make improvements to the sewer system using revenue from a sales tax approved by voters in November. The tax is expected to raise $2 million a year for road, water and sewer improvements. The city has identified $10 million in needed sewer improvements.
The city notified the public about having to pump partially treated wastewater into Hangtown Creek, issuing a press release in early February, but did not notify the public about the Feb. 20 spill of 582,000 gallons. Morris said he didn’t know why that was the case, but added that the city notified state authorities promptly about all the spills.
Social-service director Gleason said said she was surprised when a reporter told her how much wastewater had spilled near her office recently. About 100 employees and children are in the office daily.
“I don’t think we were notified of the magnitude,” she said.
Greg Stanton, director of the El Dorado County Environmental Management Division, said he did not notify residents about the Placerville spills, which tainted creeks mostly running in unincorporated parts of the county. He said the spills did not present a high risk because of dilution from stormwater and because people were not in the water during the storms. But he added that he did not know about the city’s biggest spill, nor did he see its E. coli test results. He said he could not comment further until he confirmed those results.
Sacramento Area Sewer District spokeswoman Coleman said “when it was safe and appropriate to do so, signs were posted around impacted waterways. Most of the overflows that occurred were not accessible to the public, and the public was not recreating in the waterways during these storm events.”