Trap Repairs for the Sink and Hand Basin Sink or basin trap repairs are a common issue as sometimes the trap plumbing under the kitchen sink or wash hand basin gets knocked about by something or somebody puts pressure on the weak plastic mainly the locking nut. The water starts to pass by the rubber water seal and begins leaking into the cupboard causing water damage which can be beyond repair. Trap Repair Solution How to stop a P or S trap from leaking. Option one: Never use the tap again. Not possible. More to option 2. Option 2: Try