September 12 flash flood and debris and surveyed areas. Debris flow Oak Glen Potato Canyon Birch creek (caught on video time lapse) which as 100,000 cubic yards of debris. Debris flow Valley of the Falls on Prospect street (death) up to 8 feet high with large boulders. Debris flow on Valley of the Falls road (just up the road shown in survey) which was 10 feet with another 50,000 cubic yards of debris.  Debris flow San Gorgonio River (Apple scar) with the several million damage to the water plant in Banning. There were reports of damage and flooding in Crestline Lake Arrowhead (further west) from September 11 (3 inches rain) but never got photos.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 12-SEP-22 15:00:00 to 12-SEP-22 18:00:00 (PST-8)
Location: FALLSVALE
Flood cause: Heavy Rain
Property damage: 4.00M
Crop damage: 0.00K
Reported by: Emergency Manager

Morongo Indian reservation had extensive mud, rock and logs in a major debris flow off the 2020 Apple burn scar which traveled down the San Gorgonio River. This inundated the Banning Water Plant and pushed mud, rocks and logs onto roads.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 12-SEP-22 15:00:00 to 12-SEP-22 18:00:00 (PST-8)
Location: FOREST FALLS
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

A storm survey by WCM found several debris flows on Valley of the Falls road in Forest Falls. The largest produced mud and rocks as high as 10 feet, completely covering the Valley of the Falls road. Other flash floods and debris occurred further into the canyon (deeper) affecting the roads and residences property. Homeowners discussed and described the flooding and impact. Most severe since August 2014.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 12-SEP-22 15:00:00 to 12-SEP-22 18:00:00 (PST-8)
Location: FOREST FALLS
Flood cause: Heavy Rain
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Department of Highways

A major flash flood debris flow occurred in Birch Creek through Potato Canyon. This area was affected by lesser debris flows October and December 2021 and August 2022 but this flood filled the entire channel in layers, overtopped and damage the Steakhouse restaurant in Oak Glen, took out power poles, pushed large boulder and layers of mud downstream onto Oak Glen Road and pushed up to windows on a couple homes. WCM Alex Tardy did a storm survey. Estimated 100,000 cubic yards of debris removed by San Bernardino Public Works. Video of the debris flow between 3 and 4 pm was recorded.

Flash Flood in SAN BERNARDINO, CALIFORNIA
From 12-SEP-22 15:00:00 to 12-SEP-22 18:00:00 (PST-8)
Location: FOREST FALLS
Flood cause: Heavy Rain
Property damage: 200.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

A large flash flood and debris flow occurred on Prospect street off of Valley of the Falls in Forest Falls, CA. The debris flow originated on the 2020 El Dorado burn scar after 1.1 inches of rain in an hour on Yucaipa Ridge. More than 1 debris flow occurred but the largest crossed Prospect street moving and damaging vehicles as well as damage homes. At least 2 homes had major damage. One fatality occurred when an older female was buried in debris, 3 days later found by search and rescue dogs. Residents took photos of debris flows and flash flooding including video and Ring security cameras. WCM visited the damage and SAR activity on September 13 and spoke with residents who shared additional photos and descriptions. A 20 foot boulder was lodged just above their home and their Jeep was washed down the hill (caught on Ring camera).