Chlorination moves a step closer
A contract has been awarded for the upgrade of Blenheim’s water treatment plants to enable chlorination disinfection.
Mason Engineers will begin work in early April, and the plants are expected to be up and running by October.
The upgrade is needed to ensure Blenheim’s water supply complies with the Government’s Water Services Act and Drinking Water Quality Assurance Rules.
National water regulator Taumata Arowai requires a residual disinfectant - typically chlorine - to be added to reticulated water supplies in New Zealand.
Blenheim’s water, which is delivered to 10,700 households, is currently treated for protozoa and bacteria, but has no chlorine dosing.
Chlorine is a simple and effective way of ensuring Blenheim’s water supply is fully disinfected and safe for drinking, says Taumata Arowai. It is used worldwide to purify water supplies as it can kill most common bacteria including campylobacter and norovirus.
It’s used alongside other processes such as protozoa barriers which remove or inactivate single-celled parasites including cryptosporidium and giardia. Water supplies in Renwick, Picton, Havelock, Wairau Valley, Seddon and rural Awatere are already chlorinated
Chlorine has been used to help disinfect community drinking water supplies for more than 120 years and performs multiple functions. It can be a primary form of treatment for bacteria and viruses and a secondary or residual disinfectant after primary treatment is completed, to ensure that water stays safe as it is distributed to consumers through pipe networks.
World Health Organisation studies confirm that the small amount of chlorine needed to treat drinking water is safe. The chlorine levels used in drinking water are too low to be a risk to health.
