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

Low pressure from a well usually comes from one of three places: the pump itself is failing or undersized, sediment has clogged the intake or pipes, or the pressure tank has lost its air charge. You can test which one by checking your pressure gauge — most wells should read between 40 and 60 pounds per square inch (PSI) when a tap is off. If it's below 40, or if pressure drops suddenly, one of those three problems is almost certainly the cause.

The good news is that most of these fixes are within reach of a homeowner with basic tools, though some require a plumber. The bad news is that if your pump is straightforward too small for your household's water use, you may need to replace it — which is the most expensive option but also the most permanent.

Key Takeaways

  • Check your pressure gauge first; if it reads below 40 PSI, the problem is usually the pump, the pressure tank, or sediment in the lines.
  • A waterlogged pressure tank (one with no air charge) is the easiest and cheapest fix — you can recharge it yourself with an air pump in under an hour.
  • Sediment buildup in the well intake or pipes reduces flow; flushing the system or replacing the well screen can restore pressure without replacing the pump.
  • If your pump is more than 10 years old and pressure has declined gradually, the pump itself may be worn out and need replacement.
  • A pressure tank that is too small for your household will cause pressure to drop quickly when multiple taps run at once; upgrading the tank size helps.

Check and recharge your pressure tank

The pressure tank stores water under air pressure so that your pump doesn't run every time you turn on a tap. Over time, the air charge inside the tank leaks out or gets absorbed into the water, leaving the tank waterlogged. When this happens, the pump has to work harder and pressure drops.

To test the tank, turn off the pump and open a tap until no water comes out. Then feel the top of the tank — the upper third should sound hollow when you tap it (air side) and the lower third should feel heavy (water side). If the whole tank feels heavy, it's waterlogged. You can also check the air valve on top of the tank with a tire pressure gauge; it should read about 2 PSI less than your pump's cut-in pressure (usually around 38 PSI for a 40/60 system). If it reads zero or very low, the tank needs air.

Recharge the tank yourself using a bicycle or electric air pump. Turn off the pump, drain the tank completely by opening the lowest faucet in your house, then attach the pump to the air valve on top of the tank and inflate to the correct pressure. Turn the pump back on and check your pressure gauge — it should rise back to normal within a few minutes. This fix costs almost nothing and often solves the problem entirely.

Flush sediment from your well and pipes

Sand, silt, and mineral deposits can accumulate in your well intake, in the pipes between the well and your house, or inside the pump itself. This buildup narrows the passages water travels through, reducing flow and pressure. You'll often notice this as a gradual decline over months or years, sometimes with discolored or cloudy water.

Start by flushing your house pipes. Attach a garden hose to your lowest outdoor faucet (usually a hose bib near the foundation) and run water at full force for 10 to 15 minutes. Watch the water — if it's brown or cloudy at first and clears up, sediment is coming out. Do this once a week for a month; sometimes this alone restores pressure.

If flushing the house lines doesn't help, the sediment is likely in the well itself or in the pump intake. This requires either pulling the pump to clean or replace the well screen (a mesh filter at the bottom of the well that keeps sediment out), or hiring a well service to do it. A well screen replacement costs between $300 and $800 depending on well depth and local rates. If your well is very old and the screen has never been replaced, this is often the fix.

Upgrade or replace your pump

If your pump is more than 10 to 15 years old, or if pressure has declined steadily over years despite a good pressure tank and clean pipes, the pump itself is likely worn out. Pump impellers (the spinning parts that move water) wear smooth over time, losing their grip on the water and moving less of it with each rotation.

Before replacing the pump, confirm it's actually undersized or failing. Run one tap at full flow and watch your pressure gauge. If pressure stays steady above 40 PSI, the pump is working. If it drops below 40 PSI or fluctuates, the pump is struggling. Also check how many gallons per minute (GPM) your pump is rated for — this is usually stamped on the pump housing or in your well paperwork. A typical household needs 10 to 15 GPM; if yours is rated for less and you have multiple bathrooms or heavy water use, upgrading to a larger pump will help.

Pump replacement is a job for a licensed well contractor in most states. The cost ranges from $800 to $2,500 depending on well depth, pump size, and local labor rates. A new pump usually comes with a warranty of 3 to 5 years and should last 10 to 15 years with proper maintenance.

Upgrade your pressure tank size

If your pressure tank is too small, the pump will cycle on and off frequently, and pressure will drop sharply when multiple taps run at once. A tank that's too small also wears out the pump faster because it runs more often.

Tank size is measured in gallons and is usually stamped on the side. Most homes use 20 to 40-gallon tanks; larger households or those with high water use benefit from 60 to 120-gallon tanks. If you have a 20-gallon tank and notice pressure dropping when you shower while the washing machine runs, a larger tank will help. Upgrading from a 20-gallon to a 40-gallon tank costs $300 to $600 installed and is a straightforward swap if your plumbing space allows it.

Keep in mind that a larger tank alone won't fix low pressure if your pump is failing or sediment is blocking flow. It will only help if your pump is working well but cycling too often.

Check for leaks in your system

A slow leak in your well line, pressure tank, or house pipes will cause the pump to run constantly and pressure to stay low. You may not see water pooling if the leak is underground or in the basement.

Listen for the pump running when no taps are on. If it cycles every few minutes, you have a leak. Check your water meter (if you have one) — write down the reading, wait an hour without using water, and check again. If the meter has moved, water is leaking somewhere. Underground leaks are hard to find without a leak detection service, but above-ground leaks are usually visible around the pressure tank, pump connections, or where pipes enter the house. Tighten any loose fittings with a wrench; if water still drips, the fitting or pipe section needs replacement.

Maintain your well to prevent future pressure loss

Once you've restored your pressure, keep it stable by checking your pressure tank air charge once a year (usually in spring before heavy water use). Also have your well professionally inspected every 3 to 5 years — a contractor can check the pump, screen, and tank condition and catch problems before they become expensive.

If you have a sediment filter on your well line, replace the cartridge every 6 to 12 months depending on how much sediment your well produces. A clogged filter will reduce pressure just as much as a clogged well screen. Keep records of any work done to your well — this helps you and future contractors understand what's been replaced and when.

Frequently Asked Questions

How do I know if my pressure tank is waterlogged?

Feel the top and bottom of the tank with your hand. The top third should feel hollow and light (air), and the bottom third should feel heavy (water). If the whole tank feels heavy or sounds full when you tap it, it's waterlogged. You can also use a tire pressure gauge on the air valve at the top — it should read about 2 PSI below your pump's cut-in pressure, usually around 38 PSI.

Can I increase well pressure without replacing the pump?

Yes, if the problem is a waterlogged tank, sediment buildup, or a leak. Recharging the tank, flushing sediment, or fixing a leak can restore pressure without pump replacement. If your pump is straightforward too small for your household's water use, however, you'll need to replace it or upgrade to a larger model.

What PSI should my well pressure be?

Most household wells run between 40 and 60 PSI. The pump usually turns on at 40 PSI (cut-in) and shuts off at 60 PSI (cut-out). If your gauge reads below 40 PSI when a tap is off, something is wrong — either the pump, tank, or pipes.

How much does it cost to replace a well pump?

Pump replacement typically costs $800 to $2,500 installed, depending on well depth, pump size, and your region. A pressure tank recharge costs almost nothing if you do it yourself, and a well screen replacement runs $300 to $800. Get quotes from at least two local well contractors before deciding.

Why does my water pressure drop when I use multiple taps?

Your pressure tank is too small, or your pump isn't large enough to keep up with demand. When multiple taps run, water leaves the tank faster than the pump can refill it, so pressure drops. Upgrading to a larger tank or a higher-capacity pump solves this.