State regulators will determine in the near future whether the sewer system that serves most of Sacramento County violated clean-water regulations by allowing sewage to overflow and end up in the Sacramento River early Monday morning.
The Central Valley Regional Quality Control Board will also investigate a sewage pump station failure that took place at 1 p.m. Saturday in western Galt, at the height of last weekend's storms. City crews cleaned up and disinfected the 200 block of Quail Hollow Drive, according to the California Office of Emergency Services' Web site.
The state water quality board will soon analyze whether the city of Galt, like the Sacramento Regional County Sanitation District to the north, was negligent with its sewage spill.
"It's never OK, but there are times where it happens," said Patricia Leary, a supervising engineer for the state board. "In extreme weather, we have violations occur. They are violating their permit, but it isn't clear whether they had culpability."
Some cities and sewer districts throughout California were struggling to keep the weekend's intense rainfall from causing their sewer plants to overflow into local waterways, Leary said.
The Sacramento County district, which serves the entire county except Galt and generally other areas south of the Cosumnes River, had to deal with 550 million gallons of sewage on Saturday in a treatment plant designed to handle only 400 million of gallons per day.
No problems in Lodi area
However, Lodi and the remainder of San Joaquin County didn't have any sewage spills over the rainy weekend, Leary said.
In Lodi, Woodbridge, Lockeford and Stockton, the combination of sewage and weekend rainfall was less than the sewer plant's capacity. In Galt, treated sewage was dumped into nearby Laguna Creek, but that is permitted from Nov. 1 to April 30 under Galt's current sewage discharge permit with the state, said John Griffin, an associate civil engineer in Galt.
Under the current permit, Galt is allowed to discharge treated sewage in the creek, just north of the city, because winter rains generally dilute the sewage, Griffin said.
In Lodi, Del Kerlin, the city's associate superintendent of wastewater treatment, said the White Slough Wastewater Treatment Plant was five million gallons below capacity on both Saturday and Monday, and six million gallons below capacity on Sunday.
|Sewer levels at a glance|
|Where sewage goes|
|Lodi||11.4 million||16.5 million||City-owned land near plant|
|Woodbridge||N/A||360,000||Woodbridge Sanitary District land|
|Lockeford||410,000 gallons||N/A||Land owned by Lockeford CSD|
|Galt||3 million||1 million||Laguna Creek|
|Stockton||Up to 74 million||110 million||San Joaquin River|
|- News-Sentinel staff|
Lodi typically processes about six million gallons of sewage daily, Kerlin said.
However, rainfall caused the plant to be three million gallons above the eight million gallon daily average for December, Kerlin said. The capacity is about 16.5 million gallons.
Land dedicated to absorb sewage
In the event that rainfall causes the sewer plants in either Lodi, Woodbridge or Lockeford to overflow, the rainfall/sewage combination would end up on adjacent property owned by the city of Lodi, Woodbridge Sanitary District or Lockeford Community Services District, respectively.
"It would just stay on our property," Kerlin said. "We own all our property around the plant."
In Lockeford, district manager Joe Salzman reported that the sewer plant is probably 100,000 gallons above normal. The district generates an average of 310,000 gallons of sewage per day.
In Woodbridge, plant operator Brett Moroz forwarded a call from the News-Sentinel to sanitary district board President Harold Rohrbach. Although he was unable to give any statistical information about the plant's capacity or current sewage levels, Rohrbach said the sewer plant is "in good condition."
Stockton also weathered the storm without a hitch, said Mark Madison, the city's municipal utilities director.
Its sewer plant ranged from 37 million gallons on Sunday to a peak of 74 million gallons on Monday and Tuesday, Madison said, compared with a daily average of 33 million gallons.
However, the sewage was contained to the 640 acres of city-owned sewage ponds, so there was no danger of sludge entering the city streets, Madison said.
Some Stockton sewage ends up in river
When major storms like last weekend's are forecast, Stockton workers pump sewage into the San Joaquin River, Madison said. However, such a discharge is allowed under Stockton's waste discharge permit from the state.
Stockton would need to have about 110 million gallons on a given day before worrying about sewage spilling on the streets, he added.
Meanwhile, the weekend storm also caused some swimming pools to overflow or require property owners to pump out the water. Frank Beeler, Lodi's assistant water and wastewater superintendent, said pumping pool water onto the front or back lawn would be appropriate.
The chlorine isn't likely to affect the wells or the Mokelumne River, even if pool water pumped onto the lawn ends up in the storm drain, Beeler said, because the grass and soil would absorb the chlorine first.