Fears over ‘unintended consequences’ for dam owners

Otago regional councillors are calling for more consideration of the effects that downstream developments can have on dam owners.

Yesterday, councillors approved changes to the Otago Regional Council’s dangerous dams policy — which addresses the risk of dam failure on people and assets.

Some councillors, though, said they were concerned dam-owners could be left suffering "unintended consequences" if local councils that approved new developments below dams did not consider how a land-use change could change a dam’s potential impact classification.

Cr Kevin Malcolm said the responsibility should be on developers to ensure they were "actually protecting the dam owner".

"I’m continually concerned about people or organisations that go into new areas and create — hopefully — unintended consequences for people that are already there.

"So the dam is built, it’s been sitting there, it’s been built correctly, everything’s done right, it’s ticking all the boxes, and yet it’s going to be upgraded in its importance and the risk that it has, because I’ve come in and put 1000 houses below it."

Cr Andrew Noone asked council staff to suggest to local councils that a schedule be added to district plans, listing any "dam of concern".

In that way developers could do their own due diligence.

Cr Gary Kelliher asked whether there was a mechanism available to the council to require local councils to include dam owners in their development approvals processes.

An "ongoing beef" the irrigation sector had was that local councils were "absolutely useless" at advising infrastructure owners of land-use changes they approved "and actually leaving infrastructure owners out of processes that they should really be involved in, and submitting on".

"And these schemes learn of changes when it’s far too late."

Chief executive Richard Saunders said the councillors’ concerns were addressed in the staff report presented to yesterday’s meeting.

Council staff would establish a process of notification to local councils to make sure relevant parties were aware "of any inherent risks that may arise from any land-use change that could alter a dam’s potential impact classification".

"I absolutely understand the issue, which is the risk that arises when development goes into a space — sometimes well after a dam has been there — and then the impact that has."

The council’s dangerous dams policy had been overdue for review and needed to align with Building (Dam Safety) Regulations that came into effect this month.

Crs Kate Wilson and Elliot Weir were jointly appointed to hear and decide on the council’s dangerous, earthquake-prone and flood-prone dam policy adopted yesterday.