St. Clair Shores Pump Sprinkler Winterization

Pump-fed irrigation changes the winterization procedure

Some irrigation systems operate from a dedicated pump rather than directly from municipal water. For lake-fed and other pump-fed sprinkler systems, winterization requires an understanding of both the irrigation zones and the equipment supplying those zones.

This is especially important because a pump system can contain water in locations that do not exist on a standard city-water installation.

Hunter HydroTech provides sprinkler winterization and blowout service for both pump-fed and city-water systems throughout Southeast Michigan.

Understand where the water comes from

A pump-fed sprinkler system may draw water through a suction line from a lake, well or another source. The pump then sends pressurized water through its discharge plumbing and into the irrigation mainline.

The exact arrangement varies. Pumps may be mounted indoors or outdoors, above or below other portions of the irrigation system, and the suction side can include check valves, foot valves, screens or other components.

Because of those differences, there is no responsible one-size-fits-all instruction for every pump-fed winterization.

The irrigation side still needs a zone-by-zone blowout

Even when a pump supplies the water, the downstream irrigation system still contains mainline piping, valves and individual zones. Those zones can retain water after the pump is shut down.

Controlled compressed air is used on the irrigation side to move water out through the operating sprinkler heads. Each zone should be activated so the separate lateral pipes are addressed individually.

The pump itself must be considered separately

A sprinkler blowout should not be treated as permission to force compressed air through pump equipment without understanding the installation. The pump, suction side and discharge side have different functions and may have different drainage or winter-protection requirements.

The correct approach depends on where the pump is installed, whether it is exposed to freezing temperatures, what drainage points are available and how it connects to the irrigation main.

What about the lake intake or suction line?

Lake-fed systems can include a long suction line extending from the pump toward the water source. That portion of the system operates differently from the pressurized sprinkler zones.

Its winter treatment depends on system design, elevation, check or foot-valve arrangement and how much of the piping is exposed to freezing conditions. This is another reason pump-fed irrigation should be evaluated as a complete system rather than using a generic city-water checklist.

Valves, manifolds and sprinkler heads still matter

Once water leaves the pump, the irrigation equipment is similar in many respects to other sprinkler systems. Water can remain in valve bodies, manifold fittings, lateral piping, rotors and spray heads.

Any exposed plumbing deserves particular attention because it can cool faster than buried irrigation pipe.

Shut down electrical operation appropriately

Pump-fed systems often use a pump-start relay that receives a low-voltage signal from the irrigation controller. Seasonal shutdown should leave the system in a state where the controller does not unexpectedly call for irrigation while the pump or water supply is winterized.

The appropriate electrical state depends on the specific controller, relay and pump installation.

Schedule before freezing conditions

A pump-fed system can have more components to inspect than a simple residential city-water system. Scheduling ahead of severe cold provides time to identify a leaking fitting, malfunctioning valve or pump-side issue that could complicate the shutdown.