Leaky lagoon fix proposed

Fully lining the base would cost $750,000.

A $220,000 plan is being developed to pump water from the Manawatu River to top up the slowly oozing Hokowhitu Lagoon.

The Palmerston North City Council’s sport and recreation committee on Monday supported the plan.

But the money is not in the budget, so the proposal will have to compete with other projects when the Annual Plan is reviewed for the next financial year.

That means there is a risk the water level could still be low this summer when a canoe polo tournament is planned to be hosted there.

Water levels at the lagoon began dropping faster than usual after the January 2014 Wellington earthquake.

Despite several investigations, no single crack or leak in the base that could be fixed has been identified. In the most recent tests in June, divers examined the base, and came up with no evidence of a weak spot.

Council leisure assets officer Brian Way said in a report to the committee that four other options were considered.

Doing nothing could see the water permanently retreating, leaving an unattractive area with limited recreational use.

Fully lining the base would cost $750,000.

Using a second artesian bore as a supplementary water source could restrict supplies to other users.

A variation on taking from the river could have used solar power for the pump, but would have cost $100,000 more than using conventional energy.

Way said an old pipeline from the river to the lagoon was already in place that had been used from 1976 until about 20 years ago.

It would provide the basis for the new scheme.

The council would need a consent from Horizons Regional Council for the water take.

Way said early indications were that there was capacity for the river supply.

However, on an average of four days a year, sometimes as long as a month, the river level dropped so low that it could not be used to top up the lagoon.