What Causes High Water Pressure and How Do I Fix It?

If you are reading this, you probably had a recent visit from a plumber.

Did you know:

  • Water pressure is primarily due to the elevation of storage tanks relative to the elevation of your home. 
  • Higher water pressures are in geographically low points (near a creek or the bottom of a neighborhood).
  • County building codes require pressure-reducing valves (PRVs) to be installed on new or remodeled residential plumbing if there is evidence of water pressure exceeding 80 psi.
  • You can buy a gauge at a home improvement store to check your pressure.
  • A PRV reduces the water pressure coming into your home to protect your plumbing, much like an electrical surge protector protects your computer or television.
  • Keep in mind that a PRV will age and need to be replaced. So if you notice a sudden increase in pressure in your plumbing, your PRV may be wearing out and needs to be replaced.
picture of a pressure reducing valve or PRV.

Frequently Asked Questions

Why should I care if my water pressure is more than 80 psi?

​High water pressure could cause:

  • Appliances and fixtures fail sooner than average
  • Damage water heater
  • High repair and water bills 

How would I know if I have high water pressure?

If you are experiencing any of the below situations, it is time to talk to a plumber: 

· A leaking faucet or appliance may tell you it is wearing down, and water pressure should be checked. 

· A toilet flowing water from the tank into the bowl when not in use (could also be a simple toilet repair).

· Water is spitting instead of flowing when the faucet is first turned on.

· The sound of pipes banging inside the house may note pressure fluctuations.

· Irregular changes in pressure in shower or sinks.

· Appliances failing early.

· Mineral deposit build-up (white or greenish) on the outside of a shutoff valve. 

Check with your neighbors – It may be possible that your neighbors are experiencing a similar issue. If they are not, this may indicate a problem with your private plumbing. 

What should I ask the plumber about high water pressure and pressure-reducing valves?

​A licensed plumber can assess your current plumbing and recommend whether a PRV is needed. Remember, getting more than one price quote is always a good idea.

  • Some contractors / licensed plumbers may choose to use an expansion tank (also known as a bladder) or other options to discharge high water pressure safely out of the plumbing system. 
  • A PRV can be installed three feet behind the water meter box or inside your home before the water heater.
  • Avoid installing PRVs in sidewalks or driveways. 
  • Please be sure your plumber clearly explains any warranty that may apply to the PRV and the plumber’s work.
  • PRVs will eventually need to be replaced between 7 and 12 years typically.
    • Note: If your water pressure noticeably changes, It may be time to replace the PRV.

​What if the PRV makes the water pressure too low?

· PRVs are adjustable

· Consider replacing old fixtures or pipes that may be clogged with mineral deposits

Can Charlotte Water (CLTWater) reduce the water pressure in my home?

A licensed plumber can check your pressure and determine if you need a PRV.

Customers are in water pressure zones that serve several zip codes to provide minimal pressure of 20 psi to fire hydrants for public safety. CLTWater rarely changes water pressure zones. In those rare cases, a water pressure zone is changed to help customers experiencing low water pressure.

Does water pressure fluctuate daily?

​Water pressure will vary throughout the day. Based on elevation and other factors, your home has a water pressure range that varies a few psi. You are more likely to experience the following:

  • The low range of water pressure during summer mornings when irrigation use may be high in the neighborhood
  • The high range of water pressure typically from December through February when outdoor water use is minimal

Will the City of Charlotte pay for my PRV or plumbing costs caused by water pressure?

No.

I have 80+ psi and no PRV. Why didn’t my house have a PRV installed earlier?

​When houses are built or remodeled, the water pressure should be checked. If it is over 80 psi at the time of the test, a PRV is required. The test could have been conducted at a time of day when water pressure didn’t exceed 80 psi due to other factors (water usage, etc.).

Would Charlotte Water increase my pressure?

​Changing water pressure zones is extremely rare. Most properties have been in the same water pressure zone for several decades.

If CLTWater determines that customers need to move to a different water pressure zone, you would be notified several times in advance. 

Is the water or wastewater project nearby going to increase my water pressure?

Wastewater projects won’t have any impact on drinking water pipes or pressure.

Water projects may enhance flow and stabilize pressure by cleaning or replacing old pipes. Adding larger pipes may increase water storage in the area but will not significantly affect water pressure since most water pressure is the elevation difference between the storage tank and your home.

Where does my private plumbing start?

​The property owner maintains a water pipe from the end of the meter box (including the tailpiece) to the building(s). The property owner is responsible for pipes and fixtures in the buildings and wastewater pipes until the edge of the street or street right-of-way (varies). Charlotte Water maintains the water meter up to and including the meter yoke assembly, meter box, and water and wastewater pipes under the public street.

The illustration shows that Charlotte Water maintains the water pipes under the public streets and service lines from the water main to the meter box. Charlotte Water also maintains the meter and meter box. The property owner’s private plumbing starts at the tailpiece or pipe that leaves the water meter box and piping under the private plumbing to the building and inside the building.

Does my plumbing need to be replaced?

Just as pipes under the street age and have an end of service, so does plumbing in your home. Consider planning for the eventual replacement of plumbing that exceeds 50 years.

Learn more:

Charlotte Water Pressure

Homeowner’s Responsibility (Where Does Private Plumbing Begin?)

Water Service Replacement

Fixing At Home Leaks

Water Conservation Tips

How Do Water Towers Work?