The System, Mapped in One Paragraph
Every irrigation system is the same story with different plants. Water tees off your service after the meter, passes a shutoff and the backflow preventer, and reaches a pressurized main that runs to the valve boxes. The valves hold that pressure around the clock all season, opening zone by zone on the clock's command to feed the lateral lines and heads. That geography sorts every leak into three tiers. Always-pressurized failures on the main, valve, and backflow side leak day and night. Zone-side failures in laterals and heads leak only when their zone runs. And control failures, valves that weep or stick, blur the line between the two.
Always-On Leaks: The Expensive Tier
The pressurized side is where the money goes. A cracked main or a weeping valve seat loses water twenty-four hours a day whether or not anything waters, and it does so invisibly under lawn. The tells are consistent. The meter creeps with the controller off. A valve box stands full of water in dry weather. Or one stretch of ground between backflow and boxes stays damp on its own schedule-defying clock. Closing the irrigation shutoff splits this tier from the house instantly. Acoustic locating then marks the failure along the traced main, the way any buried pressure line gets found.
The Backflow Preventer: Guardian and Suspect
The backflow assembly protects the drinking supply from irrigation water and is required equipment, and it fails in expensive little ways. Internal checks wear and dump water from the relief port, sometimes dramatically. Test cocks weep. And its exposed position makes it the system's premier freeze casualty. A backflow left wet past the first hard cold cracks its body or bonnet. That spring-startup discovery costs real money and is entirely preventable with a proper fall shutdown. Ours get tested, rebuilt with manufacturer kits when worn, and winterized correctly, and every irrigation call includes a look at it on principle.
Zone-Side Losses and the Controller's Evidence
Zone failures show up as symptoms per station. One zone with weak pressure across all heads points at a lateral split feeding the soil. A zone that geysers at one spot names a failed head or riser, and a zone that runs muddy at its valve box has trouble at the valve itself. The controller helps more than owners expect: run each zone deliberately while walking it, and the system demonstrates its own faults. Water that seeps from heads hours after watering marks a valve not seating, low-head drainage, or both, and telling those apart decides between a valve rebuild and a check-valve head swap. Head-level and lateral specifics continue on our sprinkler page, and split lateral repairs follow the plastic-pipe craft covered under PVC work.
Seasonal Discipline, Boulder Edition
This system lives and dies by the calendar. Spring startup deserves a slow, deliberate pressurization with the yard walked zone by zone, because winter's damage announces itself in the first minutes. Fall shutdown is the blowout plus the backflow drain-down, before the first hard freeze rather than after. Mid-season, the tiered bill is your monitor: usage that outruns the weather is the system asking for this page. Owners around Frasier Meadows and across the city can put the whole cycle, diagnosis, repair, rebuild, and seasonal service, on one number: (303) 552-3896.
Systems on drip zones get one extra check: emitter lines chew through fittings and stakes yearly, and a failed drip fitting soaks one shrub bed silently for a season. Walk the drip zones with the same eyes as the turf, just slower.
One controller setting worth checking today: a stuck or overridden rain sensor waters through storms, which is not a leak but bills like one and looks just as bad on the tier chart.