Choosing a Pump for Cistern-Fed Sprinkler System

I have a cistern and want to water pasture or grass using a Rain Bird or similar sprinkler. What type and horsepower pump do I need for 120V operation on an extension cord, keeping costs low?

Sizing the Pump by Flow Requirements

Sprinkler heads are rated by gallons per minute (GPM). A typical overhead head throwing 30–35 feet uses 4–5 GPM. If running one head at a time, you need a pump delivering 4–5 GPM. Pumps are often rated in gallons per hour (GPH); divide GPH by 60 to get GPM. For example, a 300 GPH pump delivers 5 GPM.

Recommended Pump Brand

Little Giant Pumps offer affordable 110–120V models ($50–$100) with outputs from 100 to 1,200 GPH. Choose a model that matches the number of heads you plan to run simultaneously. This approach keeps the system simple and cost-effective.