In the event of a plumbing emergency, the most important thing to keep focused and calm. It will help you do the right thing. Be prepared by having the contact information of a local plumber saved. Know how to shut off your main water line. Know how to cut off your water main. If you follow these steps, plumbing emergencies need to only be focused on fixing the problem and not repairing the damage that would otherwise result. t7hr18fdp7.