Saturating soil, flooding low-lying ground and knocking out power throughout western Nevada County, rainstorms hammered the Sierra Foothills Sunday morning.
Most of the damage occurred from 7 a.m. to noon, during which time the Nevada County Sheriff’s Office received more than 150 calls, most of which were weather related.
At about 5:30 a.m., a large tree fell across Highway 49 near the intersection of Carriage Drive, causing a six-car accident while striking a utility pole and causing a power outage, said Sgt. Matt Whiting of the California Highway Patrol.
No injuries were reported as a result of the accident, Whiting said, and one-way traffic was restored on the highway at 7 a.m., and the entire road was open by 10 a.m.
The Grass Valley Interagency Command also received a barrage of calls from 7 a.m. to noon, according to Brian York, a captain with Calfire.
“There was flooding due to culverts being clogged,” York said. “There was no one part of the community that was affected more than others, no particular section of the streets. It was across the board.”
Most of the calls related to flooding or trees down blocking roadways, damaging houses and propane tanks.
“The nature of the calls were not much different from other storms, but the volume of calls was larger,” York said.
Several power outages were reported throughout Nevada County Sunday, according to the Pacific Gas & Electric website.
About 5,500 PG&E customers were without power as of noon Sunday, said J.D. Guidi, spokesman for the utilities company. The number had dwindled by 5 p.m., as PG&E crews worked through the storm, said Joe Molica, another spokeman at PG&E.
At noon, two outages had occurred in proximity to Nevada City, affecting about 3,000 customers, Guidy said. By 5 p.m., 559 customers were without power.
Grass Valley has witnessed four separate outages, affecting 805 customers, during the height of the storm, Guidy said. As of press time, 259 customers were still without power. An outage in Penn Valley affected 182 customers, Molica said.
Power is expected to be restored to all customers by Monday evening, Molica said.
“We will be working through the night,” he said. “This was a really tough storm. It was the strongest of all three, but barring any access issues, everyone should be back online by tomorrow.”
The intensity of rain dissipated Sunday afternoon with scattered showers continuing through the afternoon into the evening.
Dry weather is expected to resume Monday morning, said Eric Kurth of the National Weather Service.
A flood warning will be in effect until Monday at 10 a.m., despite the torrent of rain decreasing Sunday afternoon, Kurth said.
“The abundant rainfall and excessive precipitation has caused saturation in the groundwater and streams and creeks have excessive overflow,” said Kurth.
Water levels are expected to rise Monday, and rock and land slides are anticipated to continue over the next several days, Kurth said.
So far, no major landslides have been reported in western Nevada County, but Plumas County has witnessed a few, Kurth said.
In the eastern part of the county, the Truckee River rose to a level necessitating the establishment of an evacuation center.
Motorists are advised not to drive a vehicle into areas where water covers the roadway, said Vic Ferrera, director of the Office of Emergency Services in a news release. The water depth may be too great to allow the vehicle to pass.
Individuals should pay special attention to areas beneath recent burn scars, as they are susceptible to debris flow, the release states.
“A flood warning means flooding is occurring or is imminent. Most flood-related deaths occur in automobiles,” according to the National Weather Service. “Do not attempt to cross water-covered bridges, dips or low water crossings. Never try to cross a flowing stream, even a small one, on foot.”
Grass Valley Overflow
The Grass Valley Waste Water Treatment plant, which is prone to flooding during heavy precipitation events, once again could not manage the amount of water flowing through the facility and dumped untreated or partially treated wastewater into Wolf Creek, according to environmental health officials.
At 8:30 a.m., the treatment plant began to overflow, said Wesley Nicks of Nevada County Department of Environmental Health. Wastewater was discharged into Wolf Creek from the early morning until noon, Nicks said, when contractors were able to divert the Newmont Mine waterway away from the treatment plant, reducing the flow going into the plant.
Residents along Wolf Creek were notified of the overflow and were advised not to go near the creek as wastewater represents a significant human health hazard, Nicks said.
To contact Staff Writer Matthew Renda, email firstname.lastname@example.org or call (530) 477-4239.