Is a Leak Making Your Well Pump Run?

If you're on a private well, you don't get a water bill to warn you about a leak. Instead, the clue is the pump. A pump that switches on when nobody is using water is refilling the pressure tank because water is going somewhere.

Signs the pump is running for a leak

• You hear the pump or the pressure switch click on at night or when the house is empty

• The pressure gauge at the tank drops slowly with everything off

• The pump seems to run in short, frequent bursts

• Your electric bill has crept up with no other explanation

How a well system works, in brief

Your well pump pushes water into a pressure tank. The tank holds water under pressure, so you can run a tap without the pump starting every time. When the pressure falls to a set level, the pressure switch turns the pump on. When it reaches the upper level, it turns the pump off. Anything that takes water out of the system, including a leak, eventually brings the pressure down and starts the pump.

That's why the pressure gauge is such a useful tool. It shows exactly what's happening, and it doesn't need a meter or a bill.

Step 1: Watch the pressure gauge

With every tap, appliance and irrigation system off, note the reading on the pressure gauge near the tank. Come back after an hour without using water. If it has dropped noticeably, or the pump has kicked on, water is leaving the system.

Step 2: Check the usual suspects

Faucets. Look at every spout for a drip, and open every sink cabinet to check for water on the floor or around the supply lines and valves.

Toilets. A toilet with a worn flapper can run silently. Put a few drops of food colouring in the tank, wait fifteen minutes without flushing, and look for colour in the bowl.

Outdoor spigots. Check each one, including on sheds, barns and gardens. A spigot split by freezing can leak inside a wall or crawlspace where you won't see it.

Water heater. Check the relief valve discharge pipe and the base of the tank.

Water treatment. A softener stuck in regeneration can run water to drain continuously.

Step 3: Narrow it down

If you have shut-off valves on branch lines, such as to an outbuilding, close them one at a time and watch whether the pressure drop stops. That tells you which part of the system the leak is on.

Leaks you can't see

Some leaks don't show up inside the house at all:

• The line from the well to the house. A leak in the buried supply line can create a soft or unusually green patch in the yard along its path.

• Lines to outbuildings. A buried line to a barn, shop or garden spigot can leak for months unnoticed.

• Inside walls. A spigot split by freezing, or a leaking fitting behind a shower valve, can leak inside the wall.

• Under the house. In a crawlspace, a slow leak can soak the ground without ever reaching living space.

If the pressure keeps dropping after you've ruled out everything inside, the leak may be on one of these lines.

A simple overnight test

Before bed, turn off everything that uses water, note the gauge reading and the time, and check first thing in the morning before anyone uses water. If the reading has dropped, or you heard the pump run overnight, water left the system. Repeat it with branch valves closed to narrow it down.

When it's not a leak

Frequent short pump cycling with no leak can mean a waterlogged pressure tank or a failing pressure switch. Those are well system problems rather than leaks, and need a plumber or well contractor to check.

Why it's worth fixing quickly

Every extra pump cycle adds wear to the pump and the pressure switch, and a pump that short-cycles for months can fail sooner than it should. Replacing a well pump is a much bigger job than replacing a cartridge or a spigot.

Keep a note

When you call, it helps to say how long the pump runs, how often it starts, what the gauge reads and what you've already checked. That helps the plumber narrow down where to look.

If you find a dripping faucet, see leaking faucet repair. A leaking outdoor spigot is covered in outdoor spigot repair. Properties spread across the county, like those around Crozier, often have several outdoor lines to check. For how to pinpoint a faucet leak, read how to find where your faucet is dripping.