Watercare will continue to source water from the Hoteo River to supply Wellsford and Te Hana for the foreseeable future, despite a fierce attack on its quality from Wellsford’s representative on the Rodney Local Board, Colin Smith.
Mr Smith says the Hoteo is prone to contamination from “every invasive crap you can think of”, including untreated sewage, dead animals and cyanide used to kill possums.
“Most people in Wellsford have filters on their water supply and when you cut them open they are black,” he says.
“In summer when the water is chlorinated it stinks. It just about makes you sick.”
Last July, Watercare took the Wellsford Water Treatment Plant out of service for several days after MCPA herbicide was detected that was above levels set by the Ministry of Health.
Mr Smith says the dependence on the Hoteo is especially aggravating because there is an ideal source of water in the hills north of Te Hana.
The water comes from two boreholes that were installed by the now defunct Albertland Cooperative Dairy Company, which formerly supplied millions of gallons of high quality water each week, both to the dairy factory and residences in Te Hana.
In 2005, a fire at the factory destroyed the pumping system that supplied water to Te Hana and the Rodney District Council elected to connect Te Hana to the Wellsford town supply.
Access to the bores was subsequently secured by seven farmers, who formed the North Albertland Community Water Supply Association to benefit from the water.
Pumps at the boreholes are currently able to draw 90 cubic metres of water an hour, which is used to supply water for livestock on local farms.
The water is not currently approved for human consumption, though Ray Hollis, director of the association, says the water is of good quality.
Its distinctive features are a high calcium content and a slightly elevated temperature.
Mr Smith says Watercare should be negotiating with farmers to make use of the Albertland boreholes to supply Wellsford.
“It’s better than bottled water. Millions of litres a day are going down the drain,” he says.
But Watercare water supply manager Priyan Perera maintains the Albertland supply is simply insufficient to meet the needs of Wellsford.
He says the Albertland boreholes have a sustainable yield of only 613 cubic metres a day, significantly less than the required 1,500 cubic metres a day.
He adds that the existing water supply network has been designed and constructed to operate from Wellsford reservoirs.
Reconfiguring the distribution system to accommodate a change in water source would be complex and incur significant additional costs.
Mr Perera says Watercare has been proactive in managing the potential risks associated with the Hoteo River water source and has installed processes to mitigate the risks.
“Wellsford residents receive ‘Aa’ grade water treated at the Wellsford Water Treatment Plant,” he says.
The Ministry of Health ‘Aa’ rating, indicates the quality of water is completely satisfactory and poses an extremely low level of risk.
He adds water quality testing for Wellsford exceeds Ministry of Health standards and includes continuous monitoring of submerged devices that test if treatment processes are effective.
Meanwhile, Watercare continues to search for new water sources to cope with increasing demand in Wellsford.
It has identified a potential groundwater source near the Wellsford Water Treatment Plant and anticipates beginning testing on the quality and quantity of water available from the source in September.
When the analysis of the potential new source is complete, Watercare will determine if it will replace or supplement water from the Hoteo River.