water.

But Bermuda's unique water system demands equally unique safeguards to ensure the health and safety of drinking water.

The Island is one of the few places in the world which uses a roof catchment/tank system to collect and store drinking water.

Therefore the quality of every local's tank water depends largely on how well the catchment system in maintained -- not an easy task.

The key to safe drinking water is not as easy as just keeping your roof clean and painted. There are certain suggested steps people should follow to keep protect their water.

The Department of Health's official advice on maintaining a safe tank recommends that preventive measure be taken to avert common tank water problems like stagnation.

Before any work is done on your roof make sure you block the drain pipes so that nothing enters the tank. The drain plugs should not be removed until any paint has dried and after the roof gets dowsed by the first rain shower.

The Department of Health advises that a roof be wire brushed, to remove old paint and growing fungus, before washing the roof with a 50/50 solution of Clorox and water.

And it is suggested that a roof only be painted with an approved water catchment coating.

Between paint jobs, residents should trim any overhanging trees to prevent leaves from entering their tanks.

But maintaining a clean roof is not the only way to ensure safe water -- a sanitary tank is equally as important since our water is stored in tanks that can be subject to many forms of contamination.

According to the Department of Health, a tank should be cleaned at least once every five years since sludge and other organic matter accumulates on the bottom. If untreated, the sludge will deplete the water of oxygen, leading to stagnation.

Environmental Health officer Susan Hill said: "A tank is almost like having a little pond under a house. We all know what happens to a pond, bacterial breed. If a tank is not cleaned regularly bacteria can form and bacteria is the main cause of water going bad.'' It is also recommended that the water in a clean tank be disinfected, using chlorination, once every three months. This can be done by using two ounces of Clorox for every 1,000 gallons of water.

The amount of water in a tank can be calculated by multiplying the length of the tank by the width and again by the depth in feet. Then multiply that figure by 6.25.

"It is a simple thing, but it is one of those things that people forget to do until they smell something or the water tastes funny,'' Ms Hill said. "It's like forgetting to change or check the batteries on your smoke detector.

"Without putting Clorox in a tank, bacteria is free to grow,'' she added.

"It is a frequent problem.'' It is important to remember that chlorination should only be done if the tank is clean because dirt interferes with the disinfection process and may cause potentially harmful compounds to be formed.

If you do not use much water or it tastes flat, it is suggested that you aerate it by running a garden hose from a tap to the top of your roof.

Allow the water to re-circulate back into the tank, but be prepared for the process to take a few hours.

When your water smells foul, like rotten eggs, it is often the result of oxygen depletion. If the tank is clean, aeration followed by chlorination should be enough to improve the quality.

And the Department of Health's Pest Control section keeps a supply of guppies (Gambusia fish) which will consume mosquito larvae.

"Mosquito larvae usually occurs in above-ground tanks,'' Ms Hill explained.

"The guppies are a natural way to get rid of them, but them you end up with fish in your tank.'' To prevent any insects from gaining entry to your tank, it is recommended that any vents or overflows leading to your tank be screened with fine mesh. And residents should make sure the tank top is tight fitting.

When checking your tank, if you spot any vegetation floating on the surface, remove it with a net. Vegetation on the bottom of the tank can be removed using a pool vacuum.

If you require assistance in dealing with a water problem, call the Environmental Health Section at 236-0224.