It may be caused by debris such as dirt, sand, solidified oil and grease, food particles, or foreign objects. Pollutants can block pipes if they back up due to fractures in the water main. Mineral buildup clogs pipes over time and causes the water pressure to go down, as there's less space for water to travel through.
Your house has a main water valve, usually located near the meter; the valve controls the flow of water into your home's pipes. Find the valve and check to see if it's completely open. Opening a half-shut valve is one of the quickest ways for increasing home water pressure.
Check Your Aerator
If you have especially hard water, aerators become clogged with hard water buildup, a common cause of low water pressure in kitchen fixtures. Clean your aerator for a quick and easy DIY fix. Remove the aerator from the faucet using pliers and a towel (to prevent scratching).
Clogged aerator screen
The aerator is the first to check when a faucet has low water pressure. Most faucets have aerators at the base or inserted inside the spout. Sediments, mineral deposits, or small debris can clog the aerator over time, which results in low water pressure.
A quick and easy way to increase water pressure (for homes supplied by a municipal water system) is to adjust the pressure-reducing valve, which can be found on the main water-supply pipe; look for a conical-shaped valve next to the water meter, close to where the main water pipe enters the house.
Check for a pressure-reducing valve (PRV) mounted on your water main. Most come set from the factory for 50 psi, but you can adjust them up or down by turning a screw on top. PRVs can also go bad after 10 to 20 years. So if yours is old, it might be time to replace it.
The city could be flushing hydrants.
In any of these cases, the pressure loss will be temporary. But when the water does come back online, it will definitely kick up sediment, which can clog supply valves and faucet aerators. Be prepared to flush them if the pressure seems low when the water comes back on.
If the municipal water or well-water flow is the problem, hire a licensed plumbing contractor to install a water-pressure booster pump. These powerful, electric pumps target incoming pressure and raise it to the proper level.
To return to full pressure only takes seconds. Flushing and recirculating takes minutes if you open all the taps, with the exception of tank water heaters.
If there's an accumulation of sediments in your hot water tank, it can lower your water pressure. The presence of kinks in the flexible water pipes used in water heaters can result in low water pressure. If the shut-off valve isn't fully open, water pressure can drop.
One of the most common causes of low pressure to a kitchen or bathroom sink faucet is debris or mineral buildup in the aerator. The aerator is the tiny screen that you see at the end of your faucet.
Water pressure regulator replacement: $250 to $1,000. Pipe section replacement: $500 to $4,000.
Typically, water pressure regulators cost about $50 to $100 on average1, though you could end up paying up to $2001 depending on the size of incoming water line.
Remove and clean the faucet aerator thoroughly, or replace it with a new one. Remove and clean the flow restrictor, increase the size of the flow restrictor hole, or remove it entirely and replace the aerator without replacing the flow restrictor.
Opening the main valve (Open/Turn-on)
Close all faucets except a tub or sink on the highest level of the home. Partially turn on valves slowly; extra slow for lever handles; stop after ½ revolution on wheel handle, ½ of a ¼ turn for lever handle; with water flowing, slowly turn off highest open faucet.
You can empty pipes by running the water and flushing the toilets after the water has been turned off. After draining the pipes, it is a good idea to leave the faucets open to prevent pressure build up from any water that remains. If you have an interior sprinkler system (for fire prevention) don't turn off the water.
Do All Homes Have a Water Pressure Regulator? No, and in some cases, you may not need one. Certain municipal supplies regulate their water pressure safely, but if that pressure runs above 80 psi, you'll want to protect your plumbing system by installing one.