Leaking Water Heaters can be be a disaster. The leak can further damage the water heater, the surrounding surface area, and structure of the home.
Generally you will be faced with two types of water heater leaks. Either the plumbing connections have failed and are leaking or the water heater tank itself is leaking.
Water heater tank leaks can be costly because you will need a new water heater. However, more costly than the leak is ignoring the leak. If the water heater is leaking it wont be long before the tank could fail and cause major water damage.
More commonly are leaks no the plumbing connections. In this case a plumber can quickly repair the connections in order to prevent further harm.
Be sure if you ever cut your water off to your water heater you also cut the electric breaker off. Running electricity to a water heater with no water will damage the elements and could cause a fire. Use the same precaution with gas to prevent pressure build up. If the tank will not be in use, cut your electric or gas supply off until a licensed plumber arrives.