At last - clear water flows from taps in Foxton

A sample shows the improvement in Foxton's water quality.

Foxton's water woes appear to be over, with a solution now in place to fix the notoriously brown supply the town has put up with for years.

Horowhenua District Council's Water and Waste Services manager Paul Gaydon says the problem has been fixed for good, and the solution even avoids adding more chemicals.

Mr Gaydon started working for the council 15 months ago, and has made it his mission to sort out Foxton's water. He said the fix involved modifying and optimising the treatment process.

"To put it simply, we've enhanced the removal of the organics in the water clarifier which allowed us to optimise the pre-chlorination and then provided for an autocatalytic reaction which occurs in the sand filters and removes the manganese that discolours the water. Then a lower dose of chlorination is made to disinfect the water before it enters the reservoir. All this means no more brown water."

The treatment plant's water clarifier has also been adjusted.

Mr Gaydon said that although it has now been achieved, the solution wasn't simple, as the bore water sourced for the Foxton town supply has a high organic and high ammonia content, making it challenging to treat and disinfect.

Water clarity issues were also due to manganese, a naturally-occurring groundwater mineral that had built-up on the water mains pipes which had been discolouring the water.

HDC have said that while the water was always completely safe to drink, it had an unappealing appearance, however last year it was shown as having an 'E' grading by the Ministry of Health.

In December, two public drinking stations were installed in the town to provide clean, clear drinking water as a temporary solution.

"We've done a lot of investigation work to truly understand the problem, look at all the options available, and then identify and implement the right solution to fix the problem once and for all," Mr Gaydon said.

Pipe-flushing and pH adjustments were carried out but were not considered a long-term fix, while deeper bores were investigated but turned up even dirtier water.

Mr Gaydon said treatments involving more chemicals were unsuitable, and ozone treatment too expensive, while the solution implemented had a one-off cost of $113,000.

A further saving of $45,000 annually would be made from the reducing the water mains flushing from monthly to bi-monthly. He said since they adjusted the treatment process, they surveyed four of the "biggest complainants" about Foxton's water clarity and all reported a 100 per cent improvement.

"Foxton's water clarity issues have been a long-time problem. But I was determined that they would become an ex-problem," he said.

Work to fix the water clarity issues experienced by some Foxton Beach residents would still continue, and would likely require additional water treatment plant infrastructure costing approximately $500,000.

Mayor Michael Feyen says that he was delighted that a water clarity solution for Foxton had finally been found.

"People in Foxton have noticed the huge improvement in their water. I know this, because they are keen to tell me," he said.

"Council's water services team is to be congratulated for fixing such a long-time problem experienced in Foxton, and one that some people thought could never be fixed. This is a great outcome."