Cistern to Lawn: Sump Pump Won't Work, Need Centrifugal Pump for Pressure

Submersible Sump Pump Fails for Sprinklers: Wrong Tool for the Job

Cistern 8 ft deep, 125 ft hose run. 1/3 HP submersible sump pump + garden hose → 3 ft spray. Sump pumps = high flow, low pressure (5–10 PSI).

What You Need

Centrifugal pump rated for 40+ PSI (90+ ft head). 1/2 HP minimum.

• Self-priming if pump above water.
• Submersible turbine if pump in cistern.

Pressure Math

40 PSI = 92 ft head. Friction loss in 125 ft hose (5/8") at 5 GPM ≈ 15 PSI. Net at head ≈ 25 PSI (min for rotors).

Example Pump

eBay link shows typical 1/2 HP centrifugal. Not an endorsement—just the type to seek.

Reply for Specific Models

Provide: cistern depth, hose length/size, desired heads, and I'll spec a pump.