Sonoma County calls for sewage pipeline study

In a potential solution to a two-decade-old problem, Sonoma County’s water agency has commissioned a $156,000 study of a potential pipeline carrying Occidental’s wastewater to a treatment plant in neighboring Graton.

A pipeline between the two west county hamlets would resolve the dilemma dating back to a 1997 state order banning Occidental from discharging effluent into a tributary of the Russian River.

Since 2018, the Occidental wastewater system — one of eight managed by Sonoma Water — has been trucking raw sewage 18 miles through Graton to a county treatment plant at the airport, an expensive program seen as a stopgap measure.

“This is the permanent solution,” said Mike Thompson, Sonoma Water’s assistant general manager, referring to the pipeline that would run six or seven miles beneath county roads.

Lynda Hopkins, chair of the Board of Supervisors who represents the west county, said the pipeline makes sense.

“We do not want to be seeing vehicles full of effluent on our winding country roads,” she said. “We really need to look forward to a permanent investment in infrastructure.”

The pipeline concept, seen as a possibility in five to 10 years, recently got fast-tracked in response to President Joe Biden’s $2 trillion infrastructure plan.

The plan includes $111 billion to upgrade the country's drinking water, wastewater and stormwater systems, CNN reported.

Timing is critical, Thompson said, because federal grant programs typically favor “shovel-ready” projects.

The county’s contract with Brelje and Race Consulting Engineers of Santa Rosa calls for completion of a pipeline feasibility study in six months. Assuming it proves workable, the pipeline could be built in three to six months, he said.

Graton’s Community Service District, which operates an underutilized treatment plant, is eager to take Occidental’s wastewater at a proposed receiving station on Green Valley Road west of Highway 116.

Jose Ortiz, the district’s general manager, said revenue from treating 17,000 gallons a day of Occidental’s wastewater would help stave off an impeding rate increase.

But Graton residents, angered by the prospect of 4,200-gallon tanker trucks making six trips a day to the station — a concrete pad with a connection to a sewer main — have hired lawyers and gathered a petition with 176 signatures to fight the location in a residential area.

Graton’s previous efforts to locate a wastewater depot have been abandoned in the wake of similar protests, and Ortiz agrees that a pipeline is the way to go.

“Trucking is not the final solution — it can’t be,” he said.

Thompson said the pipeline might benefit ratepayers in Occidental and Graton, an issue that will be addressed in the feasibility study.

You can reach Staff Writer Guy Kovner at 707-521-5457 or guy.kovner@pressdemocrat.com. On Twitter @guykovner.