Whanganui District Council says district well off for water - could supply neighbours

Water in Whanganui's three reservoirs would last the town at least two days without needing refilling, Whanganui District Council infrastructure manager Mark Hughes says. Photo / File

While neighbouring Rangitīkei and Ruapehu are in "dire straits" over water, Whanganui is doing okay, Whanganui District Council infrastructure manager Mark Hughes says.

With the current dry spell, he has been getting lots of queries and seeing plenty of misinformation about Whanganui's water situation, he told the council's infrastructure, climate change and emergency management committee last week.

He blames the "antisocial media" for that.

Water supplied to Whanganui is totally from artesian sources, he said, and not dependent on rain or river flows.

Over four days with five fires - including the Whanganui River Rd fire in early February - 10 million litres of water was used. Whanganui's supply recovered from that in three to four days.

Our district could give our neighbours five million litres of water a day if it was needed, Hughes said.

Whanganui's artesian water comes from several aquifers, with 70 per cent from one. That water is 2000 to 3000 years old and moves all the way from the central North Island mountains, travelling underground through limestone, which makes it "hard".

Only five to 10 per cent is drawn off en route to irrigate land, and Whanganui town takes less than 10 per cent.

Whanganui's town water eventually makes its way to the sea, when the 22 million litres a day flowing into our wastewater treatment plant is cleaned and released through the South Beach outfall.

What isn't taken from that major aquifer flows out to sea from a point near Mowhanau, Hughes said.

Whanganui's three reservoirs hold enough water to last the town 48 to 72 hours, without being replenished, and the water would last longer under restrictions.