Quick answer: A leaking water heater is most often caused by a loose drain valve, a failing temperature and pressure (T&P) relief valve, or corroded plumbing connections — all of which can usually be repaired. A leak coming from the tank itself, however, means internal corrosion has broken through, and the water heater will need to be replaced.

Few things sink a homeowner's stomach faster than a puddle spreading around the water heater. In Snellville and nearby communities like Loganville, Grayson, and Lawrenceville, most water heaters sit in a garage, basement, or interior closet — which means a leak that goes unnoticed for even a day can damage drywall, flooring, and anything stored nearby. The good news: not every leak is a catastrophe. Some are a ten-minute fix, and knowing where the water is coming from tells you most of what you need to know. This guide walks you through finding the source, the seven most common causes, what to do right now, and when it is time to call a licensed plumber.

Where Is the Water Coming From?

Before you can fix a leak, you have to find it — and water is sneaky. It runs along pipes, drips down the tank jacket, and pools in the spot that is lowest, not the spot where it started. Wipe the tank and surrounding pipes dry with a towel, then check back every 15 to 30 minutes to see where moisture reappears first.

Look at three zones. The top of the tank is where the cold-water inlet, hot-water outlet, and (on many models) the T&P relief valve connect — leaks here are usually fittings, which is the best-case scenario. The side and bottom of the tank hold the drain valve and the T&P discharge pipe — leaks here are often valve-related and still very fixable. Water seeping from the tank body itself, or from under the tank with no wet valve or fitting above it, usually means the inner tank has corroded through.

One more possibility worth ruling out: condensation. In Georgia's humid climate, a cold tank refilling on a muggy day can sweat enough to drip. If the moisture is a light, even film across the tank rather than a running drip from one point, give it a few hours — condensation dries as the tank warms.

7 Common Causes of a Leaking Water Heater

1. Loose or Failing Drain Valve

The drain valve near the bottom of the tank is used to flush sediment. Over time it can loosen, or its washer can wear out, letting water weep from the spout.

Fix: Try gently snugging the valve with a wrench — a quarter turn, no more. If it still drips, the valve can be replaced inexpensively. A hose cap on the spout is a fine temporary stop-gap.

2. Temperature and Pressure (T&P) Relief Valve Discharge

The T&P valve is a safety device that opens if the tank's temperature or pressure climbs too high. If you see water coming from the discharge pipe, the valve may be doing its job — which means the real problem is excess pressure or an overheating tank — or the valve itself may be worn and leaking.

Fix: This one deserves a professional diagnosis. A repeatedly discharging T&P valve is a warning sign, not a nuisance. Do not cap or plug it under any circumstances.

3. Loose Inlet or Outlet Connections

The cold-water inlet and hot-water outlet fittings on top of the tank expand and contract with every heating cycle. Years of that movement can loosen threaded connections and flex lines.

Fix: Tightening the fitting often solves it. Corroded or kinked flex connectors should be replaced.

4. Internal Tank Corrosion

Every tank-style water heater has a glass-lined steel tank protected by a sacrificial anode rod. Once that rod is consumed, rust goes to work on the steel. When water seeps from the tank body or pools underneath with no other source, the tank has failed.

Fix: Replacement. A corroded tank cannot be patched safely, and a slow seep can become a burst tank with little warning.

5. Excess System Pressure

High incoming water pressure, or thermal expansion in a closed plumbing system, stresses every joint and valve on the heater. It often shows up first as a weeping T&P valve or recurring drips at fittings you have already tightened.

Fix: A plumber can test your home's pressure and install or adjust a pressure-reducing valve or expansion tank. Many homes in the Snellville area were built without expansion tanks that current code calls for.

6. Worn Gaskets on Electric Models

Electric water heaters have heating elements that screw into the tank through gasketed ports. When a gasket ages, water trickles down the tank jacket below the element access panels.

Fix: Element gaskets can be replaced, but the tank must be drained and power safely disconnected first — a job best left to a pro unless you are comfortable with both plumbing and electrical work.

7. Condensation, Not a Leak at All

As covered above, a tank refilling with cold water on a humid Georgia day can sweat convincingly. Gas models can also produce flue condensation when they first fire.

Fix: Dry the tank and observe. If moisture returns evenly across the surface rather than at one point, it is condensation — annoying, but harmless.

What Should You Do Right Now?

1. Shut off the water supply. Turn the cold-water shutoff valve above the heater clockwise until it stops. If it is stuck or missing, close your home's main shutoff.

2. Cut the power or gas. For electric heaters, switch off the water heater breaker at your panel. For gas, turn the control dial to the pilot or off position. Heating an emptying tank can destroy elements and create a scald risk.

3. Contain the water. Towels, a shallow pan, or a wet vac protect flooring while you work out the source. Move stored items away from the area.

4. Identify the leak zone. Use the top, side, and bottom checks described above and note what you find — it makes any service call faster and cheaper.

5. Call for help if the leak is from the tank body. A failed tank will not improve, and the water damage from waiting usually costs far more than the replacement decision you are putting off. Henson's team handles water heater repair and replacement throughout the Snellville area.

How to Prevent Water Heater Leaks in Snellville's Climate

Gwinnett County's water is not the harshest in the country, but sediment and minerals still settle in tanks year after year, and Georgia's long cooling season keeps garages and basements humid. A few habits dramatically extend a water heater's life:

• Flush the tank once a year. Draining a few gallons through the drain valve clears sediment that otherwise insulates the burner, overworks the tank, and accelerates corrosion.
• Have the anode rod checked every 2 to 3 years. Replacing a consumed anode rod is the single cheapest way to buy your tank extra years.
• Test the T&P valve annually. Lift the test lever briefly; water should flow and then stop. A valve that keeps dripping afterward needs replacement.
• Watch your water pressure. An inexpensive gauge on an outdoor spigot should read under 80 psi. Higher readings deserve a plumber's attention.
• Put a drain pan under the tank. If your heater sits above finished space or in a closet, a pan piped to a drain is cheap insurance against the leak you do not catch on day one.

An annual plumbing checkup catches most of these before they become leaks — the same philosophy behind our HVAC maintenance visits, applied to your plumbing.

When to Call a Professional

• Water is coming from the tank body or pooling underneath with no fitting or valve leak above it
• The T&P relief valve discharges repeatedly or will not stop dripping after testing
• You tightened a fitting or the drain valve and the drip returned within a day
• The leak involves a gas water heater and you smell gas — leave the area and call your gas utility first, then a plumber
• Your water heater is 10 or more years old and leaking anywhere — repairs on a tank near end-of-life rarely pay off
• You see rusty or discolored hot water along with the leak, a classic sign of internal corrosion

If your water heater is leaking anywhere in Snellville — or in Loganville, Grayson, Lawrenceville, or Monroe — Henson Heating, Air and Plumbing can diagnose the source, give you an honest repair-or-replace recommendation, and get your hot water back the same day in most cases. Our licensed plumbers back their work with a satisfaction guarantee, and our Snellville team is local, not a call center. Call (678) 475-7622 or schedule service online today.