What Causes Low Water Pressure?

What Causes Low Water Pressure?

  • Your dishwasher and washing machine compete toe-to-toe for the water supply.
  • Everything takes twice as long when water is running from two faucets.
  • You can’t flush the toilet and wash your hands while someone is in the shower without subjecting the person showering to extremes of hot or cold water.

Low water pressure is far from ideal. And while these examples might seem a little far-fetched, they really aren’t that far from the truth. Fortunately, the only thing standing between you and proper water pressure is identifying the cause of the problem. Troubleshoot the root cause by browsing some of the more common reasons below.

Mineral Buildup in Aerator Screens

The vast majority of faucets and shower heads have aerator screens to make the water feel softer and stretch a bit farther. Minerals sometimes build up in these screens though, reducing the water pressure of that particular plumbing fixture. If your water pressure problem is limited to just one fixture, consider taking apart and cleaning the aerator screen.

Although this is a relatively rare problem, corrosion buildup inside your plumbing can, in fact, reduce the effective diameter of your pipes, thereby reducing water pressure. If this is the case, the only way to fix the problem is to replace the corroded pipe(s). If you suspect corrosion buildup as the root cause, contact a licensed plumber to discuss and further troubleshoot the issue.

Peak Periods (Home & Neighborhood)

Your entire home is hooked up to the same water supply. In fact, your entire neighborhood is. Low water pressure isn’t always abnormal during peak usage hours, especially in older or overloaded water systems. If your water pressure issue seems to come and go, it could be a result of your household or neighborhood’s greater-than-average water usage at that particular time.

Geographical Location & Elevation

The farther you are from a water tower or any pumping mechanisms the city has in place, the less net water pressure you will have. The impact of this can be reduced or increased depending on your elevation. If your house is below the average elevation for your area, you’ll likely recover any water pressure lost from distance. If your house is above the average elevation for your area, you’ll likely notice less pressure.

Water Conserving (Low-Flow) Devices

Water-conserving devices sound great environmentally speaking, but you might not be satisfied with the end result. Why? Because water conserving devices like low-flow faucets and showerheads allow less water to pass through, creating less water pressure. If you believe you have a low-flow device installed, simply replace the device with an appropriate replacement.

Poorly Performing Water Filters / Softeners

Poorly performing or malfunctioning water filters and softeners are notorious for lowering household water pressure. In many cases, the solution is to replace whatever filter the unit uses. In other more rare cases, the entire unit itself needs to be replaced. Try getting a new filter first, and if that doesn’t solve the problem, consider replacing the entire water filter / softener unit with a new one.

Water Leaks

Don’t worry… the leak doesn’t have to be in your house. Leaks in the city’s water mains can drastically reduce water pressure until they’re fixed. But there is both a plus and a minus to that. It’s not your problem; but then again, there’s nothing you can do to fix it. You have to wait for the city to fix the problem for you. If you suspect a water main leak, contact your city immediately.

Pressure Reducing Valves

If your house has a pressure-reducing valve installed, it could be the reason for your low water pressure. A pressure-reducing valve is designed to match incoming water pressure to the capacity of the plumbing in your home. If you think that your pressure-reducing valve is the problem, contact your water company or local plumber for assistance.

Partially Closed Main Shut-Off Valves

Another potential cause of low water pressure is a main shut-off valve that is partially closed (that is, not completely open). This is easy to check … just go to the main shut-off and close it completely. Then open it again, making sure that it is fully open. If that doesn’t increase your water pressure, it’s not the root cause.