The water main is a very important and integral part of any household, so it is necessary to keep it well maintained in order to avoid serious problems. A plumbing contractor will be necessary if building a new water main into a new home, replacing a water main that has finally expired, or repairing an existing main. Individual water lines are connected to city water mains, so there are a few special considerations to remember before commencing any of the above. It is important to know where everything is located when an emergency occurs. These will also be of great help to a plumber, making the needed work quicker and more efficient. It may even be enough to prevent more damage.