Signs you need a plumber: leaks, backups, water heater trouble and more

Updated November 10, 2026 · KeystoneProGuide editorial team

Which plumbing signs are emergencies?

Three kinds call for prompt action: water you cannot stop, sewage coming up into the house, and signs that a gas water heater may be producing carbon monoxide. For a burst pipe, the Philadelphia Water Department's advice is to shut off the water at the house-side valve near the meter and call a licensed plumber. The other signs below are slower, and each section says what the relevant agency suggests.

How can you tell if you have a hidden leak?

Your water meter will show it. The EPA's WaterSense program suggests reading the meter, using no water for two hours, and reading it again: if the meter changes at all, you probably have a leak. It also suggests looking at your usage in a cold month such as January or February, when outdoor watering is off; a family of four using more than 12,000 gallons a month could have serious leaks. For comparison, the Philadelphia Water Department says the average household in the city uses about 154 gallons a day.

Leaks are common and not always small. The EPA says nine percent of homes have leaks that waste 50 gallons or more a day.

What are the signs of a toilet problem?

It runs or refills on its own. The EPA says an old or worn flapper can make a toilet flush itself or silently leak thousands of gallons a year.
Color shows up in the bowl. Put a few drops of food coloring in the tank; color in the bowl after 10 minutes means a leak. Flush right after so the tank does not stain.
It needs two flushes, or it is very old. The EPA says older toilets can use as much as 6 gallons a flush, against 1.6 gallons for the current federal standard.

The EPA calls the flapper an inexpensive part that is quick to replace, and suggests a hardware store or a licensed plumber if you need help.

What are the signs a water heater is failing?

ENERGY STAR lists five red flags: visible corrosion on the tank or its water lines; water leaking from joints, seals or seams; rust in your hot water; running out of hot water sooner than you used to, often from sediment taking up space in the tank; and rumbling noises, usually sediment at the bottom. It adds that ignoring them can end in sudden failure and, in some cases, a ruptured tank and water damage.

Age is a sign in itself. ENERGY STAR suggests considering replacement once a heater is more than 10 years old, before an emergency forces the choice.

When is a gas water heater a safety concern?

When carbon monoxide may be involved. The Consumer Product Safety Commission names malfunctioning water heaters among the fuel-burning appliances that produce CO, and says early CO poisoning feels like flu without the fever: headache, fatigue, shortness of breath, nausea and dizziness. The CPSC says a malfunctioning appliance should not be used until trained personnel have serviced it, and advises CO alarms on every level of the home and outside sleeping areas.

What are the signs of a frozen pipe?

Low flow in cold weather. The Philadelphia Water Department says the first sign of freezing is reduced water flow from a faucet, and suggests checking your faucets at bedtime and again when you wake on very cold nights. If a neighbor has water and you do not, your own pipes have likely frozen. The American Red Cross says to suspect a frozen pipe if only a trickle comes out, most often on an exterior wall or where the water service enters through the foundation, and to call a licensed plumber if you cannot find or reach the frozen section.

What do slow drains and backups mean?

Water rising through basement drains is the sign agencies single out. In Philadelphia, the city's Basement Backup Protection Program exists for homes where water backs up through basement fixtures during wet weather, a sign the sewer is pushing water back into the house; the city asks you to call (215) 685-4901 while it is happening.

If the house has a septic system, a backup can mean the system is failing. Penn State Extension says a failing system can back wastewater up into the home or let it pool in the yard. The EPA says household tanks are typically pumped every three to five years.

Can you see or taste lead in water?

No, and that is the point. The EPA says you cannot see, taste or smell lead dissolved in water, so testing is the only sure way to know. The warning sign is the age of the house and its pipes rather than anything at the tap: lead pipes are more likely in homes built before 1986.

Which signs are a nuisance rather than a problem?

White scale on fixtures and kettles. Penn State Extension says hard water minerals have no adverse health effects, though they can build up in pipes and shorten a water heater's life, and that water under 7.0 grains per gallon will probably not cause major scaling. Iron and a rotten-egg smell from hydrogen sulfide are, by Penn State's account, among the most common nuisance problems in private wells; a lab test tells you which one you have.

Whether to fix it yourself or hire covers what you can safely try first, and plumbers in the area are on the plumbers directory page.

Sources

Fix a Leak Week, U.S. Environmental Protection Agency (WaterSense)
Residential Toilets, U.S. Environmental Protection Agency (WaterSense)
Financial Assistance, Philadelphia Water Department
When Should You Replace Your Water Heater?, ENERGY STAR
Carbon Monoxide Fact Sheet, U.S. Consumer Product Safety Commission
Carbon Monoxide Information Center, U.S. Consumer Product Safety Commission
All About Frozen Pipes, Philadelphia Water Department
Preventing & Thawing Frozen Pipes, American Red Cross
Basement Backup Protection Program, City of Philadelphia
On-Lot Septic System Inspections During Real Estate Transactions, Penn State Extension
How to Care for Your Septic System, U.S. Environmental Protection Agency
Basic Information about Lead in Drinking Water, U.S. Environmental Protection Agency
Water Softening, Penn State Extension
Private Water Systems FAQs, Penn State Extension