Napa, California, council approves compost facility upgrades

The city’s composting operations will become covered to mitigate odors and stormwater runoff.


Napa, California, city council has approved a major upgrade to its composting operations at the city recycling center, a report by the Napa Valley Register says. The $10.4 million upgrade at Napa Recycling and Waste Services will replace the current open-air composting with a concrete slab and 1-foot-deep top layer of mature compost meant to mitigate odors and stormwater runoff.

Air blowers and monitoring equipment will also be added to manage the organic materials’ breakdown, which takes around 45 days. The report says the upgrade will also have a redesigned drainpipe system directing stormwater into a single collection pond that can treat 1,000 gallons of runoff per minute.

Kevin Miller, the city’s recycling manager, says in the report that the improvements will increase the facility’s composting capacity from 40,000 to 66,640 tons per year. A new environmental study conducted after improvements are complete may also allow the city to process as much as 105,000 tons of organics annually.

C. Overaa & Co., Richmond, California, won the bid to construct the new compost facility, which is scheduled to be complete by February 2019.

The project’s approval is part of Napa’s effort to divert more organic waste, including food scraps and by-products, to reach its landfill diversion goal of 75 percent by 2020.