What is a pump curve and why is it important?

Every pump has a pump curve or performance curve--a graph of the overall performance capabilities of your pump. A pump curve may also be displayed in a chart format and can provide the same information.

Either way, a pump curve or performance chart displays a pump’s ability to sustain a certain flow rate (gpm) at a specific pressure (psi).

Not all pumps perform the same way, even if they are connected to the same engine. For this reason, it is important to look at a pumps performance chart or curve to know if the pump will work for your application.

If you are using one of the big sprinkler guns with your pump, the amount of water the pump will produce is all determined by the size of the nozzle on your sprinkler. The nozzle of the sprinkler(s) dictates the total flow produced by the pump.

Once you know the total flow needed by your sprinkler, the pump curve or performance curve will tell you if your pump can:

  1. Provide the necessary flow
  2. Produce the desired flow at a high enough pressure to get all the way out to your sprinkler.

Don’t forget, you want extra pressure to accommodate for the pressure losses between the pump and the sprinkler. This is where sizing your hose matters. You need to allow the total flow required to pass through with minimal friction loss and account for any significant elevation changes.