Nearly five inches were captured at Jameson Reservoir in the hills above Montecito from the rain that finally fell in torrents through the early hours on Thursday. The downpour triggered for the Carpinteria and Montecito areas first a watch alert at 2:14 a.m. and then a flood and debris flow warning at 4:50 a.m. from the Aware and Prepare early warning system. No road-blocking floods or mud flows were reported, Officer Maria Barriga with the California Highway Patrol said, though rocks and mud fell on streets in the mountain communities along State Route 154.
Gibraltar Reservoir, which collected more than five inches from the week's rain, spilled near 9:30 a.m., Shawn Johnson with county hydrology reported. The spillover is running down the Santa Ynez River, headed for Lake Cachuma, which rose by noon by more than two feet to over 32 percent full. Runoff from the watersheds flowing to both reservoirs will continue to raise Cachuma's water level for several days, said Johnson. Lake Cachuma Operations, which is run by the Interior Department's Bureau of Reclamation, has not updated its inflow and outflow report since January 15.
Gibraltar's overflow spun the stream gauge right below the dam to 8,130 cubic feet per second (CFS), or more than 60,000 gallons spewing from the dam per second. On the other side of the mountains, Mission Creek near the 101 was surging at 525 cfs at its peak at 7 a.m. Montecito Creek crested at 625 cfs at about the same time.