It is completely normal to hear a faint swooshing or gurgling sound when a faucet is on, a toilet is flushing, or an appliance like a dishwasher is running.
Hearing water run without an obvious leak usually means you have an unseen underground, slab, or in-wall pipe leak, a continuously running toilet, or water pressure issues.
Gurgling, hissing, or constant water flow noises when no fixtures are in use could be a sign of a leak, water pressure problems, or issues with the water supply line. It's essential to pay attention to these sounds and address them promptly to prevent potential water damage.
It's common to hear a light whoosh of water flowing through copper piping, PEX tubing, or older galvanized pipes when you turn on a faucet, shower, or run an appliance. Occasionally, pipes may bang or clatter as water moves through them, particularly when valves open or close quickly.
Hearing water running when no faucets are open usually means you have a hidden leak, a running toilet, or high water pressure causing pipe vibration. This issue requires immediate troubleshooting to prevent structural damage or an unexpectedly high water bill.
Learning the warning signs can help you take action before a minor leak becomes a major problem.
Yes, pipes can still burst even if the main water is shut off. Pipes burst because the water inside them freezes and expands. Turning off the water prevents continuous flooding once a pipe splits, but it doesn't remove the water already trapped inside the plumbing system.
Listen for Banging or Clanking Noises
The sound is often created by high-pressure water moving through a compromised pipe, putting stress on the entire system. Ignoring these jarring sounds can lead to a full-blown burst.
To tell if water is running through a pipe, the most reliable methods include checking the water meter for movement, listening for vibrations with a screwdriver, or feeling for temperature changes on the pipe surface. If no water is meant to be in use, any movement at the meter indicates flow.
Fortunately, noisy pipes are not often cause for concern if dealt with properly. The issue usually lies with simple issues that you can either handle yourself, or that can be dealt with through a routine call-out.
Hearing constant running water when no faucets are on usually means you have an active leak, a continuously refilling fixture, or high water pressure causing pipes to vibrate.
A constant hissing or rushing sound, often coming from the walls or floors. Gurgling or bubbling sounds when using plumbing fixtures. Whistling or clanking sounds, which may indicate water escaping from a damaged pipe.
To fix noisy water pipes in your walls, first identify the sound: a sharp bang usually indicates a pressure spike (water hammer), a rattling noise means pipes are loose, and a ticking sound is caused by copper pipes expanding as they rub against wooden wall framing.
Air in the Pipes
Air trapped inside your plumbing system can also cause pipes to knock. This usually happens when water is being drained from your system or if there is an issue with your plumbing's air chamber. Air pockets can create a knocking sound as water passes through the pipes, even when no faucets are on.
To diagnose and fix water hammer in a cold water system, check for air pockets or loose faucet washers, and consider installing a water hammer arrestor or expansion tank. "That's water hammer. Call a plumber (unless you're comfortable doing plumbing) you need a water hammer arrestor."
To quickly tell if you have an underground water leak, check your water meter for movement when all indoor taps are off, and look for physical signs in your yard like unexplained soggy patches, unusually green grass, or bubbling spots.
Plumbers use a mix of forensic deduction and specialized technology to locate hidden leaks without tearing apart your home. They generally start by assessing the property for water damage and then utilize advanced tools to pinpoint the exact source.
In plumbing, the "135-degree rule" is a code standard that dictates how much a horizontal drain pipe can bend or change direction. It limits the total cumulative angle of pipe fittings before a system requires an access point (cleanout) or must be vented, ensuring proper flow and preventing chronic clogs.
Hearing running water without a visible leak usually means there is either a hidden leak (like a slab leak or pipe in a wall), an appliance actively drawing water, or simply water moving normally through the system under high pressure.
Left unchecked, even a small hidden leak can lead to mold, structural damage, and skyrocketing water bills. The problem? Many leaks go unnoticed for weeks or even months until the damage is already done.
The increased pressure can cause a water pipe to burst, usually at a weak pipe joint but sometimes right through the pipe wall. Uninsulated pipes in unheated locations such as basements, garages, and crawl spaces are especially vulnerable to freezing.
People often assume signs of a burst pipe are obvious: rushing water sounds and flooded rooms. Unfortunately, ruptured lines can go undetected for weeks, depending on where they are and the severity of the damage.
While it may be tempting to save a few bucks on your heating bill at times, a cold snap is not the time to set back the thermostat if you have pipes that are at risk of freezing. Leave the heat on if you plan to be away during cold weather. Set the thermostat to a temperature no lower than 55° F.
Accidental water damage that occurs as a result of a sudden, unexpected occurrence like a burst pipe is often covered by a homeowners insurance policy. In addition, cleaning, repair or replacement of wood flooring, drywall and even furniture due to water damage as a result of a burst pipe typically is covered.
According to MSU, a slow drip of water will fill up a gallon pitcher in about an hour, equaling about 2 cents per night to drip one faucet. That's much cheaper than broken pipes and water damage. The faucet farthest from your water meter should be left dripping if you can only leave one running.