Upper Hutt loses 52% of its water to leaks

As a summer of severe water shortages approaches, Upper Hutt has the unwelcome title of the region’s leakiest city.

Ratepayers are forking out $14,900 a day, as 52% of Upper Hutt’s drinking water gurgles back into the ground. The amount of water being lost daily equates to 4.3 Olympic sized swimming pools.

Wellington Water last week confirmed the region is in crisis as it runs out of water. With a dry summer forecast, the implications could be severe.

Councillor Matt Carey is warning Upper Hutt residents to be prepared for a worst case scenario.

“Severe shortages can lead to network pressure loss, back-flow of contamination (this can include sewage) into your pipes: resulting in boil water – or worse, do not drink or use water – notices that take many weeks or months to end.”

Ironically, much of the region’s water comes from Upper Hutt but it earned the title of the leakiest city at the recent water summit, where Wellington Water outlined the tenuous status of the water network.

Favoured solutions involve installing water meters, increasing storage and renewing the region’s pipes.

The state of the Upper Hutt network reflects decades of underfunding, Carey said. Upper Hutt is only renewing pipes at a rate of 1.5km a year and Carey said it has to do much better.

He noted that with so much water being lost in Upper Hutt, there was little point in building a new dam.

“It's like filling a bucket full of holes.” Councils across the region were last week told the situation facing the region is serious and some households could be without water.

Across the region 44% of water is being lost to leaks and the figure for Wellington City is 41%. Wellington Water’s favoured option to fix the situation, which includes meters and new water storage facilities, would cost up to $2 billion.

Wellington Water chief executive Tonia Hoskell said that across the region, councils are not replacing pipes quickly enough.

Based on the age of the pipes in Upper Hutt and their operational life expectancy, she estimated 40% of its pipes need to be replaced over the next 30 years.

Carey noted the council is spending $10.4 million a year on drinking water and with more than half the water being lost, that equates to an approximate loss of $14,900 a day.

He urged Upper Hutt residents to have their say on water meters and what the council’s response to the water crisis should be.

NIWA meteorologist Tristan Meyer said the region is experiencing an El Niño and is also being influenced by what is currently happening in the Indian Ocean.

Last winter was one of the wettest on record, but this year it was much drier in June and July. The weather during the past couple of months had been variable but overall there had been less rain, and that was likely to continue into summer.

Over the next three months Upper Hutt and the Tararuas, where most of the region’s water comes from, would experience “normal or below normal” rainfall and it is also likely to be windier and warmer.

An indicator known as the Indian Ocean Dipole also points to a drier and warmer summer for Wellington.

The last time conditions were similar in the

Indian Ocean, there was a drought in New Zealand.

“I guess for Wellington Water this is not good news when you look at the indicators they use.”

Hoskell said that Wellington Water had updated the way it measured water loss, which had shown the approach it was using previously underestimated water loss across the region.

“Applying the improved methodology retrospectively, we estimate that water loss in Upper Hutt has increased by about 10% from the previous year.”

Hoskell said the best response to the problem is a continued focus on leak detection and fixes, universal installation of smart water meters and building more storage lakes.

Mayor Wayne Guppy said he did not accept any of the data supplied by Wellington Water was accurate, especially the water loss figure.

Upper Hutt has a programme in place to renew pipes and, based on the advice he received from staff, he was confident they were doing everything necessary to replace ageing pipes.

He said he had “no confidence” in Wellington Water and the advice it provided.

“It’s like filling a bucket full of holes.” Councillor Matt Carey