As wastewater trucks lumber their way from California’s Napa Valley to the East Bay, sanitation officials in the famed wine region are trying to come up with a more efficient way to properly process their dirty water.
According to a report this week by the North Bay Business Journal, Napa wineries typically handle their waste in one of two ways: through pretreating their wastewater, or through trucking their wastewater to East Bay Utility District’s treatment facility in Oakland.
“Napa Sanitation officials plan to gauge whether demand is worth the cost estimated in a new study to range from the same cost as hauling to Oakland up to 58 percent more,” the North Bay Business Journal said.
Officials will meet on January 27th to discuss six options they generated for the aforementioned report, which was presented at a Napa Sanitation District meeting in November.
The first proposed option is for trucks for wineries to bring to Napa Sanitation their untreated process wastewater.
According to Napa Sanitation, this option would cost 25 percent more than trucking the wastewater to the East Bay Municipal Utilities District’s Oakland location. The wastewater would then be moved to the Napa facility’s aeration basin where supplied oxygen works its magic on contaminants. This option is estimated to be able to handle 10 to 12 trucks per day in the fall months.
Another option is to pretreat wastewater, Napa Sanitation said. This alternative allows Napa to reduce the potency of the wastewater by 40 percent before it heads to the aeration basin. This option comes at a nearly six percent increase over what is currently paid by wineries to ship their wastewater to Oakland.
Officials also suggested the Napa facility could build new digesters, giant machines which essentially digest a variety of industrial waste like fat and grease. This idea would cost $15 million and would represent a 58 percent increase in costs.
Planners also said Napa Sanitation could add nine new aeration ponds which could support up to 10 trucks per day. The drawback, the report noted, is that solids would build up faster in the ponds. This option represents an 11.7 percent increase in costs.
The final viable option for the district would be to build new pretreatment systems. This option is estimated to cost the same as the current system of disposing of wastewater.
According to a September article by the Napa Valley Register, the new treatment plans come as the result of pressure from Napa winemakers.
Wineries find themselves in a conundrum, the article said, because they don’t necessarily want to ship their wastewater to Oakland – the plant receives 74 million gallons of winery wastewater a year – but keeping their water in Napa requires paying “extremely high fees” to process their water at local plants.
Via: Snooth – Articles