Water pressure determines the distance that your sprinkler heads can cover and how much space there should be between each one in your yard. 

To help you understand this better, Extreme Irrigation & Lawn explains all about water pressure and the effect it has on your sprinkler system:

How Water Pressure Is Measured

The pressure of the water in your yard and how it affects your sprinkler system is measured in pounds per square inch, which is shortened to psi. 

Most homes have a pressure between 35 and 50 psi, although that number can vary depending on how far the water travels to reach your yard. For example, if you are watering an area that is more than 60′ from the water source, you are likely to have a lower pressure than if you were watering a closer spot.

Water pressure (also called “static pressure”) is defined as the amount of pressure necessary to force water through a pipe at a constant flow rate. Water supply pressure can be measured with a gauge or can be calculated using the following formula:

Water Pressure (PSI) = (GPM) x (4.5 x π x D)

Where: PSI = Pounds per square inch, or force per square foot GPM = Gallons per minutes or volume of water flow 4.5 = a constant π = 3.141592654 = Pi D = Inside diameter of the pipe in inches

What If the System Users Different Types of Sprinkler Heads?

It is important to know that the formula above is only applicable to sprinkler head types that use rotors and emitters that have flat spray patterns.

Sprinklers with a flat spray pattern emit water at the same rate that is being pumped into the system, while sprinklers with other spray patterns will consume less water. At higher pressures, water consumption will be lower. As water pressure decreases, consumption and potential damage caused by overspray will increase.

A great example of this is the rotor spray pattern. Rotors with a spray pattern of 30 degrees or greater will tend to damage plants close to the sprinkler head. If a rotor with a spray angle of 30 degrees is used and the PSI is 40 psi, the resulting angle of the water is 15 degrees, which reduces the damage to nearby plants.

What Happens If the Water Pressure Is Either Too High or Too Low?

If the pressure is too high, it will cause the sprinkler heads to spray water farther than they are supposed to, which may result in under- or over-watering. On the other hand, if the pressure is too low, it can cause the system to use more water than it needs to and result in uneven watering.


To help you determine the water pressure for your sprinkler system, consider the following:

What type of sprinkler heads are you using? How far apart will you be placing them? How much space will there be between your sprinkler heads? How much water pressure is there in your neighborhood?

By answering these questions, you should be able to quickly determine how much space there should be between your sprinkler heads and how much water pressure is ideal for your needs when you do your irrigation system installation. 

Extreme Irrigation & Lawn is among the most reliable irrigation system installation companies in Tulsa. Contact our team today for all your irrigation needs!