California doesn’t need a full winter blowout, but freeze nights in the Conejo Valley can still crack an exposed backflow preventer or valve if your system isn’t ready. Evergreen Sprinklers has handled fall shutdown and spring startup across Ventura County since 1972, licensed under CSLB #949420 (C36 – Plumbing).
Not the way systems in cold-winter states do. You don’t need a full blowout with an air compressor here, and most of the Conejo Valley doesn’t see the hard freezes that crack buried pipe. But “no winterization needed” isn’t quite right either. Thousand Oaks, Westlake Village, and especially the canyon and hillside pockets around Oak Park, North Ranch, and Lake Sherwood do get freeze nights most winters, and a hard freeze can crack an exposed backflow preventer, an above-ground valve, or a run of pipe that isn’t buried deep enough. Those components sit in the open specifically so they can be inspected and serviced, which also means they’re the parts most exposed to a cold snap. Beyond frost risk, winter is also when a seasonal controller reprogram pays for itself: your system doesn’t need summer-length run times once the days shorten and rain starts, and leaving a summer schedule running through winter is one of the more common ways a water bill stays high for no reason. A winterization visit isn’t about surviving a Midwest winter; it’s about protecting the handful of components that are exposed to frost and dialing the schedule back to what the season actually needs.
A few things, most of them quick once we’re on site. First, we reprogram the controller for the season: shorter run times, adjusted start days, and a schedule that matches fall and winter rainfall instead of a summer heat wave. Second, we check every exposed component, backflow preventer, above-ground valves, any pipe run that isn’t buried, for freeze exposure, and where a component needs weatherproofing, we can insulate exposed pipe or handle install and repair work on the backflow assembly itself under our C36 license. Third, on systems with a drain or isolation point built in, we’ll drain or isolate the sections that call for it before a hard freeze. Last, we run the system zone by zone and check for leaks while we’re already out there. Catching a small crack or a slow drip in the fall, before winter rain and freeze cycles make it worse, is a lot cheaper than dealing with the same problem in March.
Late November through December, before the first hard freeze nights typically show up, is the right window for most of the Conejo Valley. Homes at higher elevation or in a canyon, Lake Sherwood, North Ranch, parts of Oak Park and Dos Vientos, tend to see colder overnight lows than Thousand Oaks proper, so we lean earlier for those properties. If you’ve had a frozen or cracked backflow preventer in a past winter, that’s a sign your setup needs attention before the next cold snap rather than after it.
The other half of the seasonal visit, done in spring once the freeze risk has passed. We recommission the system: check every head and valve for winter damage, clear any debris that settled in the lines over the off-season, test coverage across each zone, and reprogram the controller for a summer watering schedule that matches the season instead of the reduced winter one. A spring startup is also the easiest time to catch a head that got damaged by a mower, a valve that’s starting to stick, or a zone that isn’t covering the way it used to, before those small issues turn into a brown patch in July or a bigger repair later in the season.
Winterization and spring startup touch the same backflow preventer, valves, and controller wiring as any other irrigation repair, and when that work extends to installing or repairing a backflow assembly, it falls under our CSLB License #949420, Classification C36. Evergreen Sprinklers has served the Conejo Valley as a family-owned business since 1972, which means the same crew doing your seasonal visit can also handle whatever it finds, a cracked valve, a damaged head, exposed pipe that needs insulating, without bringing in a second contractor or scheduling a separate appointment. One licensed crew, one visit, backed by decades of hands-on experience with irrigation systems across these same neighborhoods.
Evergreen Sprinklers provides fall shutdown and spring startup service throughout Thousand Oaks, Westlake Village, Newbury Park, Agoura Hills, Malibu, Santa Rosa Valley, Lake Sherwood, Camarillo, Moorpark, Oak Park, North Ranch, Dos Vientos, Wood Ranch, and Ventura. Free on-site estimates; our trip charge is $100 for the first hour, plus parts, on any repair work a visit turns up. Call (805) 390-7437 to get on the schedule before the next freeze or before summer heat arrives.
