Did you know that toilet flushing accounts for 38 percent of household water use and that a leaking toilet can be one of the greatest sources of water waste in the home?

According to statistics produced by Fluidmaster, a major manufacturer of toilet repair parts, an average leaking toilet will waste up to 78,000 gallons of water per year. Think about it -- that's enough water to fill two average-sized backyard swimming pools.

Wasting water is expensive and the abuse of a precious natural resource. A leak also can prevent a toilet from flushing properly, which can mean multiple flushes and result in still more wasted water. What's more, the noise produced by a leaking toilet can be irritating at least and at worst the cause of sleepless nights.

The key to a smooth flushing toilet is a siphon action that is created when a rush of water is discharged from the tank into the bowl when the flush lever is depressed. The flush lever arm raises a plug, called a flapper or plunger, at the base of the tank that allows water to travel into the bowl through bowl-rinsing siphon ports located at the underside of the rim of the bowl and through a port located at the throat of toilet.

It is a combination of the volume of water and its velocity that results in a full and complete flush. Thus, a partially full tank or obstructions that reduce the velocity of the water can prevent a toilet from flushing properly.

There are several causes of a sluggish toilet that can usually be corrected with a modest investment of money and energy. In fact, toilet tank repairs are one of the most common do-it-yourself household plumbing projects.

Here are some common toilet problems and their solutions.

* Loose lever. Generally, a toilet lever is fastened to the tank by means of a threaded bushing inserted through a hole in the tank onto which a nut, typically plastic, is tightened. Over time the nut can work loose, allowing the lever mechanism to rotate in the opening, thus prohibiting it from fully raising the plunger or flapper. Simply tightening the nut will usually fix the problem.

Over time, the connection between the lever and plunger or flapper, usually consisting of a chain or rod, can become disengaged, which will prevent the stopper from being opened. This can usually be corrected by reattaching a hook or rod to the lever or stopper. When broken, a replacement rod or chain can be installed.

* Faulty flapper. The majority of toilet leaks are caused by a faulty or worn flapper. Over time, the rubber stopper at the base of the tank can become brittle, worn, dirty or misaligned with the flush valve seat, or the seat itself is so corroded that the stopper will not seal properly. This creates a leak that lowers the tank's water level, causing the fill valve to turn on and refill the tank.

A faulty flapper can be fixed by cleaning the flapper or tank ball and drain seat thoroughly, using a brush or scouring pad. If the leak persists, remove the existing flapper and replace it with a new one.

* Overflow pipe -- flush valve. Sometimes the overflow pipe or flush valve assembly can become so corroded it creates leaks that lower a tank's water level, causing the valve to turn on and refill the tank. The best fix is to replace the flush valve assembly with a new one that will work for your particular toilet.

Another overflow-related problem occurs when the water level is set too high and reaches the top of the overflow pipe when the fill valve shuts off. This results in small amounts of water pouring into the overflow pipe, causing the valve to turn on to refill the tank. This can usually be solved by setting the tank water to a lower level.

There are various ways to do this depending on the type of toilet and style of flush valve. Some valves have an adjustment screw while others have an adjustment clip located on the link of the valve. An old trick is to bend the rod that travels between the flush valve and the float ball. However, this can backfire if the rod rotates a half turn where the water line raises and water goes pouring down the drain.

* Fill valve. Another common cause of a leaky toilet is a fill valve that won't shut off. As a result, water continually pours down the overflow pipe. This is usually caused by debris that becomes lodged under the valve's seal. Debris can consist of hard water (calcium) deposits, tiny pieces of corroded pipe, pebbles or solder that are transported to the seal via the water pipe.

The simplest means of dealing with this problem is to shut off the water supply to the toilet and remove the valve top. Cover the opening with an inverted cup and turn the water on and off a few times to flush the valve and remove water line debris. If the problem persists after flushing the fill valve, the valve seal is probably cracked or split. Replacing the seal will usually solve the problem.

* Noisy-filling toilet. Sometimes a toilet can be particularly noisy when it is refilling. This is usually because of an angle adapter -- the fitting at the end of the refill tube located at the top of the overflow pipe -- that points straight down the overflow pipe. There is a simple fix to this problem that you can relate to if you have ever poured an ice cold beer into a glass. To minimize suds you tilt the glass and pour the beer against the side of the glass. The same holds true when it comes to quieting your toilet. Simply tilt the angle adapter so that the refill water is hitting the inside wall of the overflow pipe.

These are just a few of the steps that you can take to ensure the peak performance of your toilet. You'll save water, money and lots of aggravation.