Bore delayed by bacteria
Bugs have been found in water drawn from Palmerston North’s artesian sources for the first time, but were caught before they could get into the water supply network.
The discovery of bacteria, including one positive test for E coli, has delayed commissioning of a bore at Papaioea Park and prompted calls for information about the security of other bores in the city.
City council water and waste services manager Robert van Bentum said meeting drinking water standards had become a critical issue since the 2016 Havelock North tummy bug outbreak caused by the water supply.
Standards were only likely to become more stringent, and he recommended spending $550,000 on a UV treatment plant at the bore, in anticipation the treatment might become mandatory in future.
Work on the bore, the third on the site, was well under way last summer when a long, dry spring prompted water use restrictions to be imposed early.
In January, tests showed the presence of total coliform bacteria – the sort found in humans, animals and some plants.
Van Bentum said it was assumed the source of contamination was introduced during construction, as no other bores in the vicinity were affected.
The bore was flushed between January and April, but the bacteria counts persisted. Disinfection efforts failed to eliminate the problem.
The positive test for E coli meant the bore could not be commissioned until 12 months of clear tests were achieved.
Van Bentum said the clock would reset on the one-year rule every time a positive test for E coli was produced, further delaying use of the bore.
Rather than abandon the bore, he proposed installing UV treatment. Otherwise, there was no chance the bore would be able to be used this summer.
The council’s finance and performance committee recommended moving $130,000 from a budget for retaining walls at the Turitea water treatment plant access road, adding an extra $420,000 in new spending to pay for the work.
But the expensive news did not end there. In total, van Bentum recommended $1.4 million in spending this year on water supply projects to eliminate risks.
Some could be shifted from other water projects, or brought forward from planned future projects. Councillors said it was unpleasant to approve extra spending, but had no choice.