The most common bacteria found in our water supplies are E.coli, giardia and cryptosporidium. All three can cause nasty stomach problems, which generally affect younger and older people more significantly.
While mains water is generally chlorinated, this is not always the case. “The recent outbreak of bacteria in Hawke’s Bay was as a result of bacteria entering the mains water system, which was not chlorinated. Since then, it has been, but it goes to show that even with mains water systems, bacteria can and does enter the supply causing health effects to widespread parts of the population,” Puretec’s Peter Trewavas says.
But it is those who rely on rain or tank water systems as well as bore water that are at the highest risk, Peter says. “In our opinion, everyone whose home comes into this category should have a purification system installed, but we also recommended it for urban dwellings that are connected to mains water supplies.
“These types of bacteria are often spread by birds whose droppings can enter water tanks, or by dead animals getting into the tank.”
Water purification systems eliminate the risk of bacteria in the water by passing the water through a complex filtering system before it enters the house. The best of the systems incorporate a UV filter, which sterilises the bacteria and renders it incapable of reproducing.
“These are known as Hybrid UV systems. They work by way of a three-step approach. The first filter is a 20-micron pleated filter that the water passes through before going through a one-micron polyspun filter at which point it enters the UV chamber where the UV light sterilises it,” Peter says. “After this treatment, the water is classed as sediment and bacteria free.”
It is recommended that these systems are installed as close to the source of use as possible, with the usual placement where the water source enters the home. “We also offer weatherproof models too that can be mounted externally in the case that spatial or other requirements mean they can’t be placed at the point where the water source enters the home.”