Heavy rains cause sewage overflow problems

Heavy rains Tuesday night and Wednesday morning caused several sewage overflows in Sonoma Valley.

The Sonoma County Water Agency reported two wastewater spills in Sonoma and two in Boyes Hot Springs.

The four spills resulted in a total of 28,250 gallons of wastewater flowing into storm drains and a pair of nearby creeks.

The overflows ranged in size from 5 gallons a minute to 100 gallons a minute and lasted anywhere from an hour to several hours, depending on the intensity of the rain at the location, said Brad Sherwood, a water agency spokesman.

The largest overflow, 18,650 gallons, was from a manhole in the 17000-block of Highway 12 in Sonoma.

The total volume sewage spilled from the four cases equated to less than 3 minutes of inflow to the Sonoma Valley wastewater treatment plan, Sherwood said.

A vacuum truck was used to remove some of the wastewater. Agua Caliente Creek and Sonoma Creek were affected by the leaks, but water agency officials said the volume of water in both creeks at the time made it unlikely that the sewage did any harm to fish or wildlife.

- Brett Wilkison