Aquifer experts `not listening'

Draining Lake Tangonge in the early 1900s - and damaging the Aupōuri aquifer? Picture / File

A Far North man, who spoke to the Northland Age on condition of anonymity, says the draining of Lake Tangonge (the Kaitaia swamp) had a severe impact on the recharging of the Aupōuri aquifer, but the experts who believe the aquifer can continue to be exploited weren't listening.

Either they didn't understand the role the swamp once played, he said, or didn't accept it.

The aquifer has come into the spotlight once again courtesy of 24 applications to take more than six million cubic metres of water a year from it, after consents were granted for the taking of more than two million cubic metres last year.

The man, who has some experience in hydrology, said the experts who had modelled the aquifer's recharge had not taken account of the fact that 70,000 acres of hill country south of Kaitaia had once drained into the swamp. Draining the lake, which began in the early 1900s, had stopped or at least reduced recharging of the aquifer.

"Photos and news reports from the 1930s indicate that the lake flooded as high as Grigg's Corner, in Kaitaia, covering 10,000 acres or more of the Kaitaia flats," he said.

"We are fools to listen to the groundwater experts who don't know anything about our history."

The swamp, he said, had effectively served as a header tank, forcing water up the Aupōuri Peninsula.

"The commissioners [who last year granted consents to the Motutangi-Waiharara Water Users' Group] didn't have a clue about the swamp that we have spent the last 100 years draining," he added.

"The North is now covered with impervious layers that water can't penetrate, preventing the aquifer from recharging.

"Look at photos from the early 1900s and the lake looks like a harbour. I think people have forgotten just how big the lake was, and the problems with flooding in Kaitaia."

There was further evidence that the aquifer had been damaged. His father had told him of a river that had flowed across 90 Mile Beach at The Gap (Nga Tamarawaho), in the Waihopo area, which had disappeared long ago.

"Something more than just the pine trees has changed the beach," he said.

■Aquifer discussion today — page 4