How to Find Hidden Water Leaks at Home and When to Call a Plumber

Why Finding Leaks Matters

Even small leaks can add up to a lot of wasted water. The U.S. Environmental Protection Agency (EPA) WaterSense program states that the average household’s leaks can waste more than 9,300 gallons of water each year. About nine percent of homes have leaks that waste 50 gallons or more every day. Fixing common household leaks can save you about 10 percent on your water bills. This means finding and repairing leaks is good for your budget and the environment.

Common leaks include worn toilet flappers, dripping faucets, and other leaking valves. A faucet dripping just one drip per second can waste over 3,000 gallons per year. A showerhead leaking at 10 drips per minute wastes more than 500 gallons per year, according to the EPA WaterSense program.

Simple Ways to Check for Leaks

There are several easy checks you can do to find hidden leaks in your home:

The Water Meter Test

Your water meter can help you find leaks even when you don’t see any water. Here’s how:

1. Stop all water use. Make sure no one is showering, flushing toilets, running dishwashers, or using any water for at least two hours.
2. Check your water meter. Write down the reading or take a picture of the meter’s numbers.
3. Wait. Do not use any water for the next two hours.
4. Check the meter again. If the meter has moved, you likely have a leak somewhere in your home or yard. The EPA WaterSense program suggests this method as a good way to detect leaks.

The Toilet Dye Test

Toilets are a common source of hidden leaks. A leaky toilet can waste a lot of water without you even knowing it. The EPA WaterSense program suggests this simple test:

1. Lift the lid off your toilet tank.
2. Put a few drops of food coloring into the water in the tank.
3. Do not flush the toilet for at least 10 minutes.
4. Look into the toilet bowl. If you see any color in the bowl, your toilet has a leak. Flush the toilet right away after the test to avoid staining the bowl.

Review Your Winter Water Use

Your water use patterns can also point to a leak. The EPA WaterSense program recommends looking at your water bill from a colder month. If a family of four uses more than 12,000 gallons per month during a time when you are not watering your lawn or garden, you might have serious leaks.

Outdoor Checks

Leaks aren’t always inside your home. Check your outdoor plumbing too:

• Garden Hose: Check where your garden hose connects to the spigot. Look for drips or wetness.
• Irrigation System: If you have an in-ground irrigation system, check it each spring. Freezing temperatures can damage these systems. A leak about the thickness of a dime in an irrigation system can waste about 6,300 gallons of water per month, according to the EPA WaterSense program.

Common Hidden Leak Culprits

Knowing where leaks often happen can help you find them faster:

• Toilet Flappers: These rubber or plastic parts seal the water in the toilet tank. Over time, they can wear out. The EPA suggests replacing a toilet flapper at least every five years. Worn flappers are a very common cause of leaky toilets.
• Dripping Faucets: A faucet that drips constantly can waste thousands of gallons of water. A faucet dripping at one drip per second can waste more than 3,000 gallons per year, according to the EPA WaterSense program. Make sure to turn off the water line to the faucet before you try to fix it.
• Leaking Showerheads and Valves: A showerhead leaking at 10 drips per minute wastes over 500 gallons per year. Leaks can also come from shower valves, even when the shower is not in use.
• Other Leaking Valves: Check under sinks, behind appliances, and anywhere there are water supply lines and valves. Look for signs of moisture or rust.

Your Leak Detection Checklist

Use this checklist to systematically search for hidden water leaks:

• Perform a water meter test: Stop all water use for two hours, then check your meter for changes.
• Conduct a toilet dye test: Add food coloring to the toilet tank and check the bowl after 10 minutes.
• Review winter water bills: Look for high water usage during colder months when outdoor watering is low.
• Inspect all visible plumbing: Check faucets, showerheads, under sinks, and behind appliances for drips or dampness.
• Check outdoor spigots and hoses: Look for leaks where the hose connects to the spigot.
• Examine irrigation systems: In spring, look for damage or wet spots around sprinkler heads or lines.
• Listen for sounds: Sometimes you can hear running water even when no fixtures are in use.

When to Call a Plumber

While you can find many leaks yourself, some situations require a qualified professional. You should call a licensed plumber if:

• You cannot find the source of a leak after performing the recommended tests.
• The leak is in a difficult-to-reach spot or involves pipes inside walls or under floors.
• You need to repair a shower valve that drips when the shower is not in use. The EPA WaterSense program suggests an experienced handyperson or a licensed plumber for this type of repair.
• The leak involves your main water supply line or other major plumbing components that you are not comfortable working on.
• You have an in-ground irrigation system leak that you cannot fix. The EPA suggests an irrigation professional certified by a WaterSense labeled program for help with these systems.

Never attempt to fix leaks involving gas lines or electrical panels yourself. Always hire a licensed professional for these types of repairs.

When this advice may not fit

This advice is for homeowners looking to find and identify common household water leaks. If you suspect a major plumbing issue, such as a burst pipe, a problem with your main water line, or extensive water damage, you should contact a licensed plumber right away. For complex outdoor irrigation system repairs, you may need to consult with an irrigation professional. If you have any concerns about structural damage or mold growth due to a leak, you should seek advice from a qualified building professional or an environmental health specialist.