Nevada City, CA – In response to complaints about a persistent smell at Pleasant Valley Road and Highway 20, Nevada County’s Wastewater Division has installed two vaults that house an odor-control mechanism. This allows pipes to dissipate the foul air under the media in the vaults, removing the offending odors before the air reaches the surface. Many municipalities have successfully used biofilter media.
“I want to congratulate the Wastewater Division at Lake Wildwood Treatment Plant for figuring out the problem at the intersection of Pleasant Valley Road and Penn Valley Drive,” said Sue Hoek, District 4 Supervisor. “Both new filters have been installed, so I think people in that area will be very happy with that change.”
The new system should drastically reduce the noxious smell, a persistent issue at this intersection, coming from pipes installed in 2019 that carry effluent from septic tanks to the Lake Wildwood Wastewater Treatment Plant. The offender is hydrogen sulfide, a gas produced by bacteria in the wastewater flow.
“We are cautiously optimistic that this is a long-term solution and will monitor the new system. The gas is more persistent in warmer months. We are hopeful that the odor will be significantly reduced. However, we realize it may still be present at times even with the newest technology,” said Brad Torres, wastewater program manager. “Our team will continue to monitor this location and evaluate the new solution.”
The original odor control system in the problem area experienced component failures (oxygen generator, cycle pump, oxygen sensors) that made the equipment ineffective. The county next entered a pilot program that added chemicals to inhibit the offending bacteria’s growth, but that proved to be expensive and did not deliver the desired results of eliminating the smell.
If you have questions or concerns, please call (530) 265-1411 or email public.works@nevadacountyca.gov.