When a pipe bursts, a drain overflows, or a commercial water line fails, panic sets in quickly. Calling an emergency plumber is the essential first step, but what you do in the minutes before they arrive can mean the difference between minor cleanup and catastrophic structural damage.

Whether you are managing a household or running a commercial facility, following these immediate steps will help minimize damage, protect your property, and ensure your plumber can get to work right away.

1. Shut Off the Main Water Supply

Stopping the flow of water is your highest priority. Turn off the isolation valve directly behind the affected fixture (such as under a sink or behind a toilet). If the leak is severe, coming from an unknown source, or coming from a main line, shut off the property’s main water valve immediately.

2. Turn Off the Water Heater

If you have to shut off your main water line, turn off your water heater as well. For electric units, switch off the breaker at the main electrical panel. For gas units, turn the control dial to “Pilot.” Running a water heater without a fresh supply of incoming water can overheat the tank and cause burn-out or internal pressure risks.