How to Diagnose a Water Leak in Your Home—and Why You Should Do It Before You Call the Plumber

Get your wrenches ready. Finding and fixing many common plumbing leaks just may be easier than you think.

If you suspect a hidden leak, your water meter has just become your best friend. Roman Zaiets/Shutterstock

Leaky pipes increase your water bill, may cause structural damage, and can lead to mold and its ensuing Pandora’s box of complications. The good news is that suspecting you have a leak means you’re already on your way to fixing the problem.

There are two types of leaks: visible—such as water puddling beneath a sink, possibly due to a loose drain joint—and hidden. If you suspect a hidden leak, your water meter has just become your best friend. Even if you ultimately end up calling a plumber, by following the tips below you’ll be able to save him some time and, in turn, save yourself money.

Meter Diagnosis

Water meters are commonly found near the street, typically under a manhole-style cover. Ideally, you should have a water meter key, available at any hardware store, to open the manhole cover and turn the water supply on and off. If you don’t, an oversized screwdriver will open most covers, and pliers and some elbow grease will control the water supply.