Introduction

When mold is discovered, one of the most critical first steps is stopping the moisture source. Mold thrives in damp conditions, and eliminating moisture is the key to halting further mold growth. One of the most common sources of indoor moisture problems is water leaks, whether from a burst pipe, appliance failure, or plumbing malfunction.

Understanding how to quickly and effectively shut off water in an emergency can prevent further water damage, mold growth, and structural issues. This lesson covers how to locate and operate emergency water shut-off valves, ensuring that you can respond immediately when a water-related incident occurs.

How to Locate Your Emergency Water Shut-Off Valve

Every home has a main water shut-off valve that controls water flow to the entire property. In an emergency, this is the first place you should go to stop a water leak.

Where to Find It

• Inside the Home:

• Typically located near the perimeter of the house, often where the water main enters the home.

• Common locations include:

• Basements or crawl spaces (near the front wall of the house).

• Utility rooms or closets where plumbing is accessible.

• Garages (especially in warm climates where pipes are not buried deep).

• Outside the Home:

• In some cases, the shut-off valve is located at the water meter near the street or curb.

• Look for a utility box in the yard marked “Water” or “Meter.”

💡 Tip: If you don’t know where your shut-off valve is, find it now before an emergency occurs. Take a picture of it for reference and ensure all household members know its location.

How to Turn Off the Water in an Emergency

Once you’ve located the main water shut-off valve, follow these steps:

Turning Off an Indoor Valve (Ball Valve or Gate Valve)

• Ball Valve (Lever-style handle)

• Common in newer homes.

• Turn the lever 90 degrees (perpendicular to the pipe) to shut off the water.

• Gate Valve (Round handle)

• Found in older homes.

• Turn the handle clockwise (right/tighten) until it stops.

Turning Off an Outdoor Valve (Street Shut-off)

• Locate the water meter box outside.

• Open the lid (may require a wrench or screwdriver).

• Inside, find the shut-off valve and turn it with a water meter key or adjustable wrench.

• Turn clockwise until the water stops flowing.

🚨 Caution: Some outdoor shut-off valves may belong to the water company. Contact your utility provider if you’re unsure whether you can turn it off yourself.

Individual Appliance and Fixture Shut-Offs

If the leak comes from a specific appliance or fixture, turning off the water supply to that unit may be sufficient.

Key Shut-Off Locations

• Toilets – Look for a small valve behind the toilet. Turn clockwise to shut off.

• Sinks – Locate the shut-off valves under the sink and turn clockwise.

• Washing Machines – Turn off the hot and cold water valves behind the machine.

• Water Heaters – Shut off both the water inlet valve and gas/electric supply if needed.

• Refrigerators (with water dispensers/ice makers) – Usually found behind or beneath the fridge.

🔹 Shutting off only the affected appliance may allow continued water use elsewhere in the home.

What to Do After Shutting Off the Water

Once the water is shut off, take these immediate steps to prevent further damage:

✅ Soak up standing water using towels, a wet vacuum, or a mop.

✅ Ventilate the area using fans (if no mold is present) or open windows.

✅ Check for leaks—Ensure water has fully stopped before turning the system back on.

✅ Call a plumber if you’re unable to fix the issue yourself.