Quick answer
If your water heater is leaking, shut off the power or gas to the tank, close the cold water inlet valve on top of the tank, and (if the leak is major) close the main water shut-off for the house. Soak up what you can, keep anyone away from any pooling water around electrical equipment, and if you smell gas near the heater, leave the building and call FortisBC's gas emergency line or 911 from outside. A tank that is actively leaking from its body usually needs replacement, not repair.
Hot water tank leaks in Surrey, Langley, Delta and White Rock almost always come from one of five places: the temperature and pressure relief (T&P) valve, the drain valve at the bottom, the cold or hot water fittings on top, the tank itself, or condensation that only looks like a leak. The source matters because a dripping valve or a loose fitting may be a $40 repair, while water weeping from the bottom of the tank almost certainly means the tank is done.
This guide walks through how to find the source safely, how to shut gas and electric tanks down the right way, what counts as an emergency, and where permits and licensed trades fit in under BC rules.
Make it safe first
Before you investigate, do these three things in order. Water, electricity and gas combined are the dangerous part — a few minutes of setup makes everything after it safer.
- Cut the energy source. For an electric tank, go to your main panel and switch off the double-pole breaker labelled "water heater" or "HWT." For a gas tank, turn the gas control knob on the front of the tank to OFF (or PILOT as a minimum if you can't locate OFF). You can also close the gas shut-off on the pipe feeding the heater.
- Close the cold water inlet. Find the valve on the cold water pipe entering the top of the tank (usually a lever or round handle) and shut it. This stops more water from entering the tank. If that valve is seized or missing, close the main water shut-off for the whole house instead.
- Open a hot tap. Opening a hot faucet upstairs breaks the vacuum and slows the drip while you work.
Safety: If you smell natural gas (rotten egg odour) near the heater, do not operate switches, phones or anything else that could spark. Leave the house with doors open behind you, then call FortisBC's gas emergency line or 911 from outside.
Find where the leak is actually coming from
Dry the outside of the tank with a towel, put down paper on the floor around and under the heater, and watch for 10–15 minutes. The first spot that gets wet is almost always the real source.
Top of the tank
Water on top usually points to the cold or hot water connections, the T&P valve inlet, or (on some models) the anode rod port. Teflon tape failures and loose nuts are common. These are generally fixable without replacing the tank.
T&P valve and its discharge pipe
The T&P valve is a safety device, typically on the side or top, with a copper pipe running down to within a few inches of the floor. A slow drip here can mean the valve itself is failing or the tank pressure is too high (thermal expansion, a closed expansion tank, or a thermostat set too hot). Replacing a T&P valve is a defined gas or plumbing job in BC — do not simply cap the discharge pipe. The pipe is open-ended on purpose so you can see when the valve relieves.
Drain valve at the bottom
If the plastic or brass drain valve on the lower front of the tank is weeping, you may be able to snug it or cap it with a brass hose cap. If it won't stop, treat it as a sign the tank needs attention.
Water pooling under the base
Water seeping from under the tank or from the seam between the jacket and the base almost always means the inner steel tank has corroded through. There is no safe DIY patch. Plan for replacement — see hot water tank replacement cost in BC for current pricing, permit and rebate information.
Fittings, flex connectors and the shut-off valve
Check the flexible braided connectors (if present), the dielectric unions, and the shut-off valve on the inlet. A green crust is a slow leak that has been happening for a while.
Condensation that looks like a leak
On a cold morning after heavy use, moisture can condense on the outside of a cold tank or on cold pipes above it and drip down. If the "leak" vanishes once the water in the tank reheats and the pipes warm up, it was condensation. This is harmless by itself but can indicate the thermostat is set too low or that incoming water is unusually cold.
How to shut down a gas water heater
- Turn the gas control dial on the front of the tank to OFF.
- Close the yellow- or red-handled gas valve on the gas pipe feeding the heater (handle perpendicular to the pipe = closed).
- Close the cold water inlet valve on top of the tank.
- If the tank is still filling the pan or floor, close the main house water shut-off.
Do not try to relight the pilot while the tank is being investigated for a leak, and never relight if you smell gas.
How to shut down an electric water heater
- Go to the main electrical panel and switch off the double-pole breaker for the water heater. If breakers aren't labelled, shut off the main breaker.
- Close the cold water inlet on top of the tank.
- Keep hands and tools out of any standing water around the tank until the breaker is confirmed off.
Safety: Never run an electric water heater "dry." If the tank has drained and you turn the power back on with no water inside, the heating elements will burn out in seconds. Fill the tank fully (open a hot tap and wait for a steady stream of water) before restoring power.
When a leaking water heater is an emergency
Treat it as an emergency — act now, call for help — in any of these cases:
- You smell natural gas near the tank, or you hear a hissing sound. Leave the building and call FortisBC's gas emergency line or 911.
- Water is spraying, not dripping, or the floor is filling faster than you can mop. Close the main house water valve and, if the leak is at the city side of the service, call the City of Surrey water line at 604-591-4152 during business hours, or 604-591-4431 after 4:30 pm on weekdays and on weekends.
- Water is reaching the electrical panel, a furnace, or any live outlet. Shut the main breaker from a dry position and keep people away.
- The tank is bulging, the jacket is deformed, or the T&P valve is venting steam continuously. This can indicate overpressure. Shut off energy and water and keep the area clear.
- Carbon monoxide alarm sounding at the same time. Leave the house and call 911.
If you simply have no hot water but no visible leak, start with no hot water, what to check before anything else.
Repair or replace?
| What's leaking | Typical outcome |
|---|---|
| T&P valve dripping | Replace the valve; check pressure and temperature setting |
| Drain valve weeping | Tighten, cap, or replace the valve |
| Loose fitting or flex connector on top | Reseal or replace the fitting |
| Water from under the jacket/base | Replace the tank — repair is not safe |
| Rust at seams or scale falling out of an aging tank | Plan replacement even if the leak is small today |
If you decide to replace, Technical Safety BC requires a gas permit for installing or replacing a water heater and other gas appliances, and homeowner permits are only available for people who own and solely occupy a single detached dwelling — not strata, duplex or home-business owners, who must hire a licensed contractor. Once a homeowner permit is issued, at least one inspection must be requested within 180 days.
Tip: Set the thermostat so hot water at the tap is no hotter than 49 °C (120 °F) to reduce the risk of scalding, especially with young children in the home. Keep the tank itself hot enough that Legionella bacteria don't grow — many installers address both by using a mixing valve.
While you wait for a plumber or gas fitter
- Mop or vacuum standing water. A wet/dry shop vac on a GFCI outlet, well away from the tank, is faster than towels for anything more than a cup.
- Move cardboard boxes, laundry, and anything else that absorbs water out of the room so you can see where water is coming from.
- Photograph the tank's serial/data plate, the valves, and the floor around it. Your plumber, insurer, and the permit inspector will all want this.
- Check the pan under the tank (if your home has one). If it's full, you have more time by draining it rather than letting it overflow.
- If you rent, tell your landlord in writing right away so repairs and responsibility are documented.
Frequently Asked Questions
Is a leaking hot water tank dangerous?
It can be. The three risks are electric shock if water reaches live wiring or outlets, scalding from stored water that can be 60 °C, and — on gas tanks — fire or carbon monoxide if the leak damages the burner or venting. A tank that is actively dripping from the body also loses pressure and can start venting steam.
Why is my water heater leaking from the bottom?
Three common causes, in order of likelihood: the drain valve isn't fully closed, the T&P discharge pipe is routing water to the base, or the inner tank has corroded through. If drying everything and watching for 15 minutes shows water reappearing from under the jacket, the tank itself has failed and needs replacement.
Can I just turn off the water and keep using the tank?
Only briefly. Once the inlet is closed, the tank still holds a full load of hot, pressurized water and will keep leaking until it empties. On an electric tank, if the water level drops below the top element while the breaker is on, the element will burn out. Shut power off as well as water.
How much does it cost to fix a leaking hot water tank in Surrey?
A new T&P valve, drain valve, or flex connector is a small plumbing job. Replacing the tank is a much larger job that in BC requires a gas permit for gas tanks and electrical work for some electric swaps. See the current pricing, permit and rebate details on hot water tank replacement cost in BC.
Do I need a permit to replace a leaking water heater myself?
If you own and solely occupy a detached house, you can apply to Technical Safety BC for a homeowner gas permit and do the work yourself. Owners of strata units, duplexes, and homes used for a business must hire a licensed contractor. In every case, an inspection must be requested within 180 days of the permit being issued.
What should I do first — call a plumber or a gas fitter?
For a gas water heater, a licensed gas fitter can handle both the gas disconnection and the tank; for an electric water heater, a plumber usually handles the whole job and will coordinate with an electrician if the circuit needs changes. For a quick emergency shut-off, you don't need either — you can do the steps above yourself.
My basement is flooding — who do I call?
If the water is coming from your tank, shut off the main house valve and call a plumber. If it's coming from the city side of your water service, call the City of Surrey at 604-591-4152 during business hours, or 604-591-4431 after 4:30 pm on weekdays and on weekends. For storm or ground water, see sump pumps in Surrey, BC.
Official sources
- FortisBC — Gas leaks and odour
- Technical Safety BC — Homeowner Gas Permits
- Technical Safety BC — Home Modifications
- City of Surrey — Water
- Parachute Canada — Hot tap water burns and scalds
General information only, not professional advice. Rules and prices change, so check the official sources above before you act. Spotted something out of date? Tell us.