Homeowner guide · Leaks
Hidden water leaks: the 2-hour meter test for Tredyffrin and Easttown homes
Most hidden water leaks can be found with two free tests: reading your water meter before and after two hours of no water use, and a 10-minute food-coloring test in the toilet tank. Here is how to run both, and what EPA says leaks cost.
Key takeaways
The short version
- EPA says the average household’s leaks can waste more than 9,300 gallons a year.
- Meter test: read the meter, use no water for two hours, read it again. A change usually means a leak.
- Toilet test: a few drops of food coloring in the tank; color in the bowl after 10 minutes means a leak.
- EPA says fixing easy leaks can save about 10 percent on a water bill.
- A family of four using more than 12,000 gallons a month in winter may have a serious leak.
How much water leaks waste
Leaks are rarely dramatic. A running toilet or a dripping faucet wastes water quietly, every hour of every day. These are EPA’s figures (EPA WaterSense):
| Leak | Water wasted (EPA estimate) |
|---|---|
| Average household, all leaks | More than 9,300 gallons a year |
| Faucet dripping once per second | More than 3,000 gallons a year |
| Showerhead dripping 10 times a minute | More than 500 gallons a year |
| Irrigation leak 1/32 inch across | About 6,300 gallons a month |
| All U.S. households combined | Nearly 1 trillion gallons a year |
EPA also says 9 percent of homes have leaks that waste 50 gallons or more per day.
Step 1: check your winter water use
EPA suggests looking at your water use during a colder month such as January or February, when outdoor watering is not inflating the numbers. If a family of four uses more than 12,000 gallons a month, there could be serious leaks (EPA WaterSense).
Pull up a winter bill and compare the gallons with that benchmark. A smaller household should expect to use less.
Step 2: the 2-hour meter test
- Turn off every tap and make sure no appliance is running: dishwasher, washing machine, ice maker, irrigation.
- Write down the reading on your water meter.
- Use no water at all for two hours.
- Read the meter again. If the reading has changed, you probably have a leak (EPA WaterSense).
Run the test when the house will be empty, such as when everyone is at work or school. If the meter moves, the leak could be anywhere between the meter and your fixtures, including pipes you cannot see.
Step 3: the 10-minute toilet dye test
Toilets are a common source of silent leaks. EPA’s test takes ten minutes (EPA WaterSense):
- Put a few drops of food coloring in the toilet tank.
- Do not flush. Wait 10 minutes.
- If color shows up in the bowl, the tank is leaking into the bowl.
- Flush right away so the dye does not stain.
A worn flapper is the usual culprit. EPA suggests replacing the flapper at least every five years, and taking the old one to the store so the replacement matches.
Step 4: look for leaks you can see
Faucets
Check gaskets and fittings for water on the outside. EPA says to shut off the water line before replacing worn washers or gaskets.
Showerheads
Tighten the connection to the pipe stem, seal it with pipe tape, and check the washer or O-ring inside.
Garden hoses
If a hose leaks at the spigot, EPA suggests replacing the washer and tightening the connection with pipe tape and a wrench.
Irrigation
Inspect in-ground systems each spring before use for damage from frost or freezing.
When the meter moves but you cannot find the leak
If the meter test shows a leak and the toilets, faucets and showerheads check out, the leak may be in a buried service line, under a slab or inside a wall. That is the point to call a plumber for leak detection rather than opening walls on a guess.
Who repairs a leak between the street and the house depends on which side of the curb it is on. Our guide on Aqua vs. homeowner water lines explains the split.
When to call
Meter moving and no leak in sight?
We track down hidden leaks in homes across Wayne, Strafford, Paoli, Chesterbrook, Berwyn and Devon, and we fix what we find. Call (610) 788-0042.
Frequently asked questions
Water leak questions
Answers by John, Tredyffrin Easttown Plumber.
How do I check my house for a hidden water leak?
Read your water meter, use no water for two hours, then read it again. EPA says a change in the reading probably means a leak.
How do I test a toilet for a leak?
Put a few drops of food coloring in the tank and wait 10 minutes without flushing. Color in the bowl means a leak. Flush afterward to avoid staining.
How much water does a dripping faucet waste?
EPA says a faucet dripping once per second can waste more than 3,000 gallons a year.
How much can fixing leaks save?
EPA says fixing easily corrected household leaks can save about 10 percent on water bills.
How often should I replace a toilet flapper?
EPA suggests replacing the flapper at least every five years.
How much water use is too much for a family of four?
EPA says if a family of four uses more than 12,000 gallons a month in a colder month, there could be serious leaks.
Sources
Where these facts come from
Every figure and rule in this guide comes from the public sources below. Rules and fees can change, so confirm with the source before you act.
Keep reading
Related services and guides
Who fixes the water line
Aqua vs. homeowner.
Water line repair
Service line leaks and replacement.
Toilet repair
Running and leaking toilets.
Faucets and fixtures
Drips and worn parts.
Our service area
Plumbing across Tredyffrin Township, PA
Tredyffrin Easttown Plumber serves every neighborhood in Tredyffrin Township, including Wayne, Strafford, Chesterbrook, Paoli, Berwyn, Devon, Daylesford, and Howellville, plus neighboring Easttown Township. Our office is at 217 Conestoga Rd, Suite 10, Wayne, PA 19087.
