Your first line of defense should be to survey your house or apartment for leaks. An occasional or slow drip might not seem like a big deal, but it can add up to 10,000 gallons of water wasted every year, according to the EPA. You should check kitchen and bathroom faucets, toilets and pipes, and one way to do that is by reviewing your water meter readings. Here's a simple test that we've found useful: Create a two-hour period where no water is used. Note the meter reading before and after: If you see any changes at all, leaks are likely at hand. If you're unsure of how to pinpoint the source of a leak or do the repair yourself, enlist the help of a professional to avoid making the problem even worse.