Lake Casitas crept nearer to spilling this week, marking what can be a primary for the drought-stressed reservoir in additional than 25 years.
The Ojai Valley lake was over 96% full as of Tuesday. When the water will attain the spillway stays to be seen. Mike Flood, normal supervisor of the Casitas Municipal Water District, stated it might be as quickly as subsequent week.
The lake final spilled in 1998. It got here shut once more in 2005, however the district stopped diverting water from the Ventura River to gradual issues down throughout a harmful storm season.
Since then, the lake stage dropped to record lows during a yearslong drought. Casitas, which will get no imported water, fell under half full in 2015 for the primary time because it had crammed a long time earlier. Water ranges stored falling. District officers had been taking a look at extreme water restrictions in 2022.
Again then, most wouldn’t have anticipated the turnaround that occurred over the previous two years, stated Mary Bergen, a Casitas board member. However the historical past of California has been one among floods and droughts.
“We’ve got to cope with each,” she stated. “We’ve got to be ready for each.”
When did Lake Casitas first spill?
The lake, which offers ingesting water for the Ojai Valley and elements of Ventura, bounced again as final yr’s storms pushed the water level over 50% after which 70% capability. For the primary time in years, residents weren’t required to curb their water use or danger fines.
Now, a second wet winter has edged it nearer to full. At capability, the reservoir is designed to carry sufficient water to make it by means of a 20-year drought, officers stated.
Bergen referred to as the practically full lake a ravishing sight.
“It’s great to see the lake up and have a very good water provide,” she stated.
Lake Casitas was OK’d by federal officers in 1956 and development on the dam was accomplished just a few years later. It took greater than a decade earlier than the lake crammed, slowly masking outdated ranches, roads and a faculty. Since, the spillway has operated eight occasions from 1978 to 1998.
What occurs if Lake Casitas spills?
Water might attain the spillway within the subsequent seven to 10 days, Flood stated Tuesday. And not using a main storm, the amount of the movement is predicted to be comparatively low.
The district additionally would shut off diversions from the Robles facility as water reaches the spillway, Flood stated. Roughly 30 to 40% of the movement into the lake comes from the diversion facility. Further water comes from Coyote Creek and Santa Ana Creek.
The spillway, designed to maintain water from overtopping the dam, funnels the surplus into Coyote Creek.
Throughout final yr’s storms, mud and debris built up alongside a stretch of the creek downstream of the dam close to Camp Chaffee Highway. The issue led to flooding within the Foster Park neighborhood and left much less room for extra flows. Plans name for clearing sediment later this yr.
Authorities will proceed to observe circumstances, stated Patrick Maynard, director of the Ventura County Sheriff’s Workplace of Emergency Providers. Spilling throughout excessive depth rainfall could also be a priority, however low volumes possible will not trigger points, he stated.
“It’s one thing we’re simply going to want to observe,” he stated.
How shut is Lake Piru from spilling?
Over the previous month, the smaller Lake Piru additionally inched towards its capability, pushing the japanese Ventura County reservoir near spilling.
Final March, water breached the Santa Felicia Dam’s spillway for the primary time in practically twenty years. Since, it has teetered near doing it once more. Earlier this yr, officers on the United Water Conservation District stated a spill in back-to-back years has only happened three times for the reason that dam was constructed within the Nineteen Fifties.
A number of massive storms had pushed water ranges as much as the lip of the spillway final yr. However this winter, there have been extra gaps in between the rainfall, United’s Chief Engineer Maryam Bral stated. The lake ranges stayed under that mark.
As a substitute, the district has launched water into decrease Piru Creek by means of a system of pipes and valves over the previous a number of weeks, she stated. Late final yr, United additionally launched some water to create further storage and let areas downstream recharge. The lake was round 40% full heading into the winter storms, officers have stated.
Cheri Carlson covers the setting and county authorities for the Ventura County Star. Attain her at cheri.carlson@vcstar.com or 805-437-0260.
This text initially appeared on Ventura County Star: Dams inch closer to spilling in Ventura County, California
