Why Well Water Pressure Drops and What You Can Do

Well water pressure falls when the pump can't pull water fast enough, when sediment clogs the system, or when the pressure tank loses its air charge. Unlike city water, where pressure comes from a distant reservoir, your well depends on a pump and tank working together—and both can wear out or need adjustment. The good news is that most pressure problems have a straightforward fix you can understand and sometimes handle yourself.

Before you call a well contractor, you need to know where the pressure is actually lost. Is the problem everywhere in the house, or only at certain fixtures? Does it happen when you run multiple taps, or all the time? The answer tells you whether the issue is the pump, the tank, or something in between.

Key Takeaways

  • Low pressure from a well usually means the pressure tank has lost its air charge, the pump intake is clogged with sediment, or the pump itself is failing.
  • You can check the pressure tank's air charge yourself with a tire gauge on the air valve—it should read 2 pounds per square inch below your system's cut-in pressure.
  • Sediment buildup in the well or intake line is common in older wells and requires either flushing or professional cleaning depending on how severe it is.
  • A pressure switch that is stuck or miscalibrated will prevent the pump from running at all or from reaching full pressure.
  • If pressure drops only when you run multiple fixtures, the pump may be undersized for your household's peak demand.

Check and Recharge the Pressure Tank

The pressure tank stores water under air pressure so the pump doesn't run every time you turn on a tap. Over time, the air charge inside the tank leaks away, and the tank fills with water instead. When this happens, the pump cycles on and off constantly and never builds enough pressure.

To check the air charge, locate the air valve on top of the tank—it looks like a tire valve. Turn off the pump at the pressure switch or breaker. Open a tap to release all pressure from the tank until water stops flowing. Use a tire gauge to read the air pressure in the valve. It should be about 2 pounds per square inch (psi) lower than your system's cut-in pressure. If your pump normally turns on at 30 psi, the air charge should read about 28 psi.

If the reading is too low or zero, the tank needs recharging. Use an air compressor with a tire chuck to add air until you reach the correct pressure. Do not overcharge—too much air pressure can damage the tank or prevent the pump from turning on. If the tank loses its charge again within a few weeks, the internal bladder has failed and the tank must be replaced.

Clear Sediment from the Well Intake

Sediment—sand, silt, and mineral deposits—accumulates in the well and clogs the intake screen or pump inlet. This is especially common in older wells or after heavy rain. When sediment blocks the intake, the pump works harder but pulls less water, and pressure drops even though the pump is running.

You can try flushing the system yourself. Turn off the pump. Locate the cleanout plug or valve at the lowest point of the well line (usually in the basement near the pressure tank). Open it slowly to let sediment-laden water drain into a bucket until the water runs clear. This may take 15 to 30 minutes. Close the valve, turn the pump back on, and check whether pressure improves.

If flushing does not help, sediment may be deeper in the well or stuck to the pump intake. A well contractor can pull the pump and clean the intake screen, or use a jetting service to flush the well from the top. This is not a DIY job—wells require a licensed contractor to avoid contamination or damage to the casing.

Inspect and Adjust the Pressure Switch

The pressure switch tells the pump when to turn on and off. If the switch is stuck, corroded, or set too low, the pump will not run at full capacity or may not run at all. A stuck switch is one of the easiest problems to spot and sometimes to fix.

Listen to the pump. If it is not running when you turn on a tap, the switch may be stuck in the off position. Turn off power to the pump. Locate the pressure switch—a small box mounted on the pressure tank or nearby pipe. Gently tap it with a rubber mallet a few times. This can sometimes free a stuck contact. Turn power back on and test a tap.

If the pump runs but pressure is still low, the switch may be set too low. Most switches have a nut on top that adjusts the cut-in pressure (when the pump starts). Turning it clockwise raises the pressure. Make small adjustments—one-quarter turn at a time—and test the pressure with a gauge. Do not raise the pressure above the tank's rated maximum, which is usually printed on a label on the tank. If adjusting the switch does not help, it needs replacement by a well contractor.

Look for Leaks in the Pressure Tank or Lines

A leak in the pressure tank or the water line between the tank and the house will cause pressure to drop, especially when you run multiple fixtures. Water escapes instead of building pressure in the tank.

Inspect the tank visually for cracks, rust, or wet spots. Check all visible pipes and connections for drips or spray. If you find a leak on a pipe fitting, try tightening the connection with a wrench. If the leak is on the tank itself or continues after tightening, the tank or line must be replaced.

A less obvious leak is a slow drip from the pressure relief valve—a small valve on top of or side of the tank. If water drips from it constantly, the valve is faulty and should be replaced. If it only drips when pressure gets very high, the valve is working correctly and protecting the tank.

Evaluate Whether Your Pump Is Undersized

If pressure is normal when you use one or two fixtures but drops when you run the shower and washing machine at the same time, your pump may not be large enough for your household's peak demand. This is not a malfunction—it is a capacity problem.

Well pumps are rated by gallons per minute (gpm). A typical household pump delivers 10 to 15 gpm. If your home has multiple bathrooms or high-demand appliances, you may need a larger pump. A well contractor can test your system's flow rate and recommend an upgrade if necessary. Replacing a pump is a professional job that requires pulling the pump from the well and installing a new one.

Before upgrading the pump, make sure the pressure tank is large enough. A tank that is too small will not store enough water to meet peak demand, and the pump will cycle too often. A contractor can advise whether a larger tank, a larger pump, or both will solve the problem.

When to Call a Well Contractor

Call a licensed well contractor if pressure does not improve after you have checked the air charge, flushed the intake, and inspected the switch. Also call if you see cracks in the tank, if the pump will not run at all, or if pressure is so low that fixtures barely flow even after adjustments.

A contractor can pull the pump to inspect the intake screen, test the pump's output, replace a faulty pressure switch, or install a new pump or tank. They can also perform a water test to rule out contamination if pressure loss is accompanied by discolored or cloudy water.

Frequently Asked Questions

How do I know if my pressure tank's air charge is low?

The pump will run constantly or cycle on and off very frequently, even when you are not using water. You can confirm by checking the air valve with a tire gauge—it should read about 2 psi below your system's cut-in pressure. If it reads zero or very low, the air charge has leaked away.

Can I replace the pressure tank myself?

Replacing a tank requires draining the system, disconnecting the pump and plumbing, and installing a new tank with the correct air charge. It is possible for a homeowner with plumbing experience, but most people hire a contractor to avoid mistakes that could damage the pump or introduce contamination.

What is the normal water pressure for a well system?

Most well systems are set to cut in at 30 psi and cut out at 50 psi, meaning the pump runs when pressure drops to 30 and stops when it reaches 50. Some systems run at 40/60 psi. Your pressure gauge will show you what your system is set to—check the label on the pressure switch or tank.

Why does my water pressure drop when I run the dishwasher and shower together?

Your pump cannot deliver enough water to both fixtures at once, so pressure falls. This usually means the pump is undersized for your household's peak demand, or the pressure tank is too small to store enough water. A well contractor can test your system's flow rate and recommend whether you need a larger pump, tank, or both.

Is low water pressure a sign that my well is running dry?

Low pressure alone does not mean the well is dry—it usually points to a pump, tank, or switch problem. However, if pressure is low and the pump is running constantly without building pressure, the well may be low on water. A contractor can check the water level in the well and advise whether you need to deepen it or install a new well.