Water pressure is the unsung hero of irrigation. Without sufficient pressure, an automated sprinkler system simply cannot run. And achieving just the right amount of water pressure within a system is a primary factor in maintaining a healthy lawn and lower water bills. When water pressure is too high or too low, the efficiency and integrity of the irrigation system immediately decline.
A less-than-healthy lawn may be the result of an irrigation system water pressure issue.
Water Pressure vs. Water Flow
Many people think that “water pressure” and “water flow” are the same thing, but they’re not. Water flow refers to the movement of water through the sprinkler system. Simply put, it is how much water is moving and how fast. Water pressure is the force behind the water. Think of it like a straw. Water pressure is the force, or speed, of the water as it travels through the straw, while flow is how much comes out of the other end.
From Water Meter to Sprinkler Head
Calculating water pressure within a system begins at the home’s water meter. Water enters the system at that point at its maximum force. As it travels through the sprinkler system, it passes through a backflow preventer, valves, the main line, and lateral lines. That initial blast of pressure is gradually slowed by friction. How much change in pressure occurs from the water meter to the sprayer head depends on the design of the sprinkler system.
The backflow preventer is where the water pressure is first decreased. Designed to protect drinking water from contamination, it keeps water flowing in one direction, but its internal check valves and mechanisms create resistance. To minimize loss of pressure, a professionally installed, quality backflow preventer is a must.
Next, water passes through the control valves, which direct the flow to different zones within the property. Pressure is further reduced as water is forced through the valves, where mineral buildup or internal wear over time can also increase resistance. Valves should match the flow and pressure requirements of the system, and regular maintenance will help avoid losing pressure.
Friction reduces pressure even further as water runs through the main line and pipes to reach sprinkler heads. However, friction can be reduced by larger diameter pipes, fewer sharp bends, or fewer additional fittings – which is why determining the most efficient pipe layout prior to installation is essential.
Water pressure that’s too high will cause water to come out as a fine mist, which will be carried away by wind or evaporate before it can even reach the soil.
Water’s last stop before hitting the lawn is the sprinkler heads. Different varieties of sprinkler heads require different levels of water pressure to operate properly. The specific operating pressure of sprinkler heads typically ranges from 30–50 PSI. Oftentimes, it is the sprinkler heads that will alert a homeowner that there is an issue with pressure in the irrigation system.
Troubleshooting Low Water Pressure Issues
When it appears that a system’s water pressure is too low, it’s best to address the issue as soon as possible. Low water pressure drastically affects a sprinkler system’s efficiency and results in inconsistent coverage.
Under- or over-watered spots in the lawn may be indicators of water pressure issues. Additional system factors that can decrease water pressure in an irrigation system include faulty valves, leaks in main or lateral lines, clogged sprinkler heads, or line obstructions from root intrusion. Left unchecked, too little – or too much – water pressure will stress system components and shorten its life expectancy.
To properly address water pressure issues, it’s best to work with sprinkler system specialists, like the Heinen Irrigation team! Their professional expertise and specialized equipment allow them to diagnose and correct pressure issues without causing additional stress on a system. A full audit from the irrigation experts at Heinen is the best way to identify and locate a problem and to find the most effective solution – but don’t wait! When water pressure issues are not addressed in a timely manner, the risk of costly system damage increases dramatically.
Homeowners seldom think about water pressure until it’s too late. If sprinklers are sputtering, misting, or missing the mark, call in the Heinen Irrigation pros to keep your lawn and gardens lush, green, and growing.
