If a pipe breaks under the kitchen sink, close the shut-off valves under the sink right away, or the main water valve if those valves will not stop it. If the broken pipe is the drain, simply stop using the sink and dishwasher until it is repaired.
Supply Pipe or Drain Pipe?
Under a kitchen sink, there are two kinds of pipes. Supply lines bring hot and cold water to the faucet and are under pressure, so a break sprays or flows steadily. Drain pipes carry water away and only leak when the sink or dishwasher drains. Knowing which one broke tells you how urgent it is.
If a Supply Line Broke
- Turn both shut-off valves under the sink clockwise
- If they will not turn, close the main valve for the house
- Unplug the garbage disposal only if the outlet area is dry
- Empty the cabinet and dry the floor
If a Drain Pipe Broke
Stop running water in the sink and do not run the dishwasher, since it drains through the same pipe. Place a bucket under the break. Plastic drain parts often crack at the slip nuts or where the disposal connects. A loose nut can sometimes be snugged by hand, but a cracked pipe needs replacing.
Protect the Cabinet and Floor
Kitchen cabinets are often made of particleboard that swells when wet. Remove everything stored under the sink, dry the area, and leave the doors open with a fan blowing in. Check the floor in front of the cabinet and the ceiling below if the kitchen is on an upper floor.
Pictures of the cabinet and floor can help with any claim later.
If water keeps coming even with the valves closed, having a plumber come out promptly is the next step. For older valves and lines under the sink that need updating, you can set up a kitchen plumbing check by calling (833) 603-1840.