If you are experiencing a total water outage or have had a sudden, drastic decrease in water pressure, please contact Customer Service at 402.554.6666 or toll-free at 1.800.732.5864.
The normal pressure within the Metropolitan Utilities District (M.U.D.) water system largely depends on elevation. Water main pipes in low-lying areas along creeks and valleys will have relatively higher pressure than the mains at hill tops and along higher elevations of the city. Water pressure might also fluctuate during peak demand times. In the Omaha area, the heaviest demand for water occurs early in the morning during summer weekdays due to lawn irrigation.
M.U.D. is required to maintain a minimum of 20 pounds per square inch (PSI) of pressure in our water mains for water quality. But during normal operations, our main pressures will usually be at least 40 PSI. Along creeks and lower elevations of the city, the pressure can be as high as 170 PSI.
Most home improvement stores sell inexpensive water pressure gauges that can be attached to your outside faucet or hose spigot that you can use to measure the water pressure at your home or business. Most water pressure and flow concerns are due to plumbing system problems that originate inside the home. If you are having problems with low flows and/or high or low pressure, here are some steps you can take that may help resolve the issue.
PRESSURE REDUCING VALVE
Most residential pressure and flow problems are caused by a malfunctioning or out-of-adjustment pressure reducing valve (PRV). PRVs are plumbing devices installed on your water service that lower the water pressure from the M.U.D. water main. Most PRVs can be adjusted between 25-75 PSI. The PRV is usually dome or bell shaped and 3 to 4 inches in diameter. They are usually located near where the water line enters the home. They can be near the shut-off valve, water heater, water softener or located by your water meter. Below is a picture of a common PRV used in M.U.D.’s service area, but there are many other manufacturers and styles:
PRVs do wear out over time and periodically need to be replaced, but sometimes they can be adjusted. M.U.D. does not adjust PRVs since it is part of the property owner’s plumbing system. To adjust a PRV, loosen the lock nut around the base of the threaded stem on top, then turn the stem clockwise to increase the pressure, or counterclockwise to decrease the pressure. All these adjustments are best done while someone has a sink turned on and is monitoring the flow and pressure. If the adjustment helps, then retighten the lock nut. After making any adjustment to a PRV the static pressure (when no water in the house is running) should be checked with a water pressure gauge at a faucet or hose spigot, to be sure it stays below 80 PSI.
M.U.D. recommends any work done on your plumbing system be performed by a Licensed Plumber.
Water softeners can cause a sudden change or decrease in water pressure. To check it, switch the water softener to bypass mode and see if pressure improves. If it does, the low pressure is likely caused by the water softener, and it may need to be serviced or replaced.
If low pressure is only affecting the hot water in your home, there could be a problem with your water heater. Most water heaters have a shut off valve on them, check and make sure that it is fully open. You may need to consult a licensed plumber to evaluate the condition of your water heater and to service or replace it.
If only one faucet has low pressure, the problem may be a clogged aerator. Examine the aerator screen for debris, rust, scale or other particulates that restrict flow. This commonly occurs when water service is shut off. Without pressure in the indoor plumbing system, mineral particles adhering to your pipes flake off and become trapped in the aerator filter. Clean or replace the aerator.
The master water shut-off valve is usually located where the water service line comes into the home and before it goes to a water heater or water softener. If this valve is partially closed it will affect water pressure throughout the entire home. Plumbers may close this valve when they come to do work on your home. Homes with small children also will find this valve mysteriously closed. Check that the valve is completely open.
A common problem in older homes is tuberculation, which causes a reduction in water flow rate. Over time, mineral deposits and corrosion sediment accumulate on the interior of galvanized pipes. This internal build-up of minerals and corrosion does not pose a safety concern, but it does cause weaker flow. This decreases the diameter of the interior pipe, creating a more turbulent and restricted path for the water to flow through.
Unfortunately, the only way to fix tuberculation is to have a licensed plumber replace the service line and/or indoor plumbing. Switching to water conserving fixtures like low-flow showerheads and faucet aerators may help.