Why your well pressure drops and what you can do about it

Low water pressure from a well usually comes from one of three places: a pressure tank that has lost its air charge, a clogged intake line or filter, or a pump that is wearing out. The fastest fix is often the simplest — checking whether your pressure tank still has air in it. If that is not the problem, you will need to identify whether the issue is upstream (at the well or in the line coming from it) or downstream (in your house plumbing). Once you know where the problem lives, the fix ranges from something you can do yourself in an afternoon to something that requires a well contractor.

Key Takeaways

  • A waterlogged pressure tank — one that has lost its air charge — is the most common cause of low well pressure and can often be fixed by draining and recharging it yourself.
  • If pressure is low everywhere in the house, the problem is likely at the well or in the line from the well; if it is low in only one area, the problem is in your house plumbing.
  • A clogged sediment filter or intake screen can reduce pressure significantly and should be checked before assuming the pump is failing.
  • Well pumps typically last 15 to 25 years; if yours is older and pressure has declined gradually, replacement may be the only solution.
  • A pressure tank that has failed completely will need to be replaced, which usually costs between $500 and $2,000 depending on tank size and your region.

Check and recharge your pressure tank

Your well system uses a pressure tank to store water under pressure so the pump does not run constantly. Inside the tank is a rubber bladder that separates water from air. Over time, that air charge leaks out, and the tank becomes waterlogged. When this happens, pressure drops even though the pump is working fine.

To check the tank, turn off power to the pump at the breaker. Locate the air valve on top of the tank — it looks like a tire valve. Use a tire pressure gauge to check the pressure. Most residential well systems should read between 40 and 60 pounds per square inch (psi), depending on your system. If the gauge reads zero or very low, the tank has lost its charge.

To recharge it, use an air compressor to pump air back into the valve until it reads about 2 psi below your pump's cut-in pressure (the pressure at which the pump turns on). If you do not know your cut-in pressure, 38 psi is a safe starting point for most homes. Turn the pump back on and check your water pressure at a faucet. If pressure improves noticeably, the tank was the problem. If it does not, move to the next section.

Locate where pressure is actually low

Before you call a contractor, determine whether the problem is at the well or in your house. Turn on a faucet at the kitchen sink, then turn on a faucet in the basement or laundry room. If pressure is low everywhere, the problem is upstream — at the well, the pump, or the line running from the well to your house. If pressure is normal in some areas and low in others, the problem is in your house plumbing, and you should focus on that area.

You can also check pressure directly using a pressure gauge. Screw a gauge onto an outdoor faucet or a hose bib near the pressure tank. Normal household pressure is 40 to 80 psi. If the gauge reads below 40 psi, you have a genuine pressure problem. If it reads above 80 psi, your pressure regulator may be set too high — that is a separate issue worth addressing, but it is not low pressure.

Clean or replace your sediment filter and intake screen

A sediment filter sits between your well and your pressure tank and catches sand, silt, and debris before they reach your pump. Over months or years, this filter clogs and restricts water flow. A clogged filter can reduce pressure by half or more.

Locate your filter — it is usually a cartridge-style canister mounted on the line coming from the well. Turn off the pump. Open the filter housing (usually a large bowl at the bottom) and pull out the cartridge. If it is visibly dirty or discolored, replace it with a new one of the same size and micron rating. Your well contractor or the original system documentation will tell you what size you need. If you do not have that information, bring the old cartridge to a plumbing supply store and they can match it.

While you have the filter open, check the intake screen — a fine mesh screen at the bottom of the well casing that prevents sand from entering the pump. If it is clogged, you will need a well contractor to clean or replace it, because it requires pulling the pump out of the well. This is not a do-it-yourself job.

Check for leaks in the well line

A crack or pinhole leak in the line running from your well to the house can cause pressure to drop gradually. The leak may be underground, so you cannot see it, but you can often detect it by listening or by watching your pump cycle.

Turn off all water use in the house and listen near the pressure tank. If you hear water running or hissing, there is a leak. Another sign is if the pump turns on and off frequently even when no one is using water — this is called short cycling and suggests water is leaking out of the system.

If you suspect a leak, call a well contractor. They can pressurize the line with air to locate the leak, and then either repair or replace the section of pipe. Depending on where the leak is and how deep the well line is buried, this can range from a few hundred dollars to over a thousand.

Evaluate whether your pump is failing

If your pressure tank is charged, your filters are clean, and you have no leaks, the pump itself may be wearing out. Well pumps typically last 15 to 25 years. If yours is older than 20 years and pressure has declined slowly over time, replacement is likely the answer.

A failing pump will often show other signs: it runs longer to fill the tank, it cycles on and off more frequently, or it makes unusual noises like grinding or squealing. If the pump is still under warranty or relatively new, a well contractor can sometimes rebuild it, but this is less common than full replacement.

Pump replacement is not a do-it-yourself job — it requires pulling the pump out of the well, which demands specialized equipment and knowledge of electrical connections. Expect to pay a well contractor $1,500 to $3,000 or more, depending on well depth, pump size, and your region. Get quotes from at least two contractors before deciding.

Install a booster pump if the well itself is weak

In some cases, the well itself does not produce enough pressure — either because it is shallow, the water table is low, or the well was never high-capacity. If a well contractor has ruled out all other causes, a booster pump can increase pressure artificially.

A booster pump is a small, separate pump installed after your pressure tank that takes water at whatever pressure the well provides and pressurizes it further. This is more expensive than fixing an existing problem — installation typically costs $1,500 to $2,500 — but it works when the well itself is the limitation.

Before installing a booster pump, have a well contractor test your well's flow rate and recovery time. A booster pump cannot create water that is not there; if your well produces only 5 gallons per minute, a booster pump will give you 5 gallons per minute at higher pressure, but not more water overall. If low pressure is really a symptom of low flow, a booster pump alone will not solve the problem.

Frequently Asked Questions

Can I increase pressure by adjusting the pressure switch?

You can adjust the pressure switch to turn the pump on at a higher pressure and shut it off at a higher pressure, which will increase the pressure at your faucets. However, this is a temporary fix that puts extra strain on the pump and tank. If pressure is genuinely low, adjusting the switch masks the problem rather than solving it. Have a contractor diagnose the real cause first.

How often should I recharge my pressure tank?

A healthy pressure tank should hold its charge for several years. If you are recharging it more than once a year, the bladder inside is likely failing and the tank should be replaced. Frequent recharging is a sign the tank is at the end of its life.

Will a water softener affect my well pressure?

A water softener adds some resistance to flow, but it should not significantly reduce pressure if it is sized correctly for your household. If you installed a softener and pressure dropped noticeably, the softener may be undersized or the filter inside it may be clogged. Check the softener's manual for cleaning instructions.

What pressure should my well pump be set to?

Most residential well pumps are set to cut in at 40 psi and cut out at 60 psi, meaning the pump turns on when pressure drops to 40 and shuts off when it reaches 60. Your system may be different — check your pump documentation or ask a well contractor. Do not adjust these settings without knowing what they currently are.

Is low well pressure dangerous?

Low pressure is not a safety hazard by itself, but it can be inconvenient and may indicate a problem that will get worse. If pressure is very low, you may not have enough flow for showers or filling a bathtub. More importantly, low pressure sometimes signals a leak or a pump that is about to fail, so it is worth investigating rather than ignoring.