An unprecedented freeze and thaw cycle during July has caused damage to several roads in the Queenstown Lakes District this winter.

The highest ever number of ground frosts, 30 from 31 days, was recorded for July with the number of air frosts reaching 27 consecutive days, a figure last recorded in 1876.

"On top of the frosts we have experienced one of the warmest Julys in some time and those conditions have played havoc with the road surface," Queenstown Lakes District Council contracts manager Chris Hawker said.

In particular Malaghans Road and the Crown Range were sustaining widespread pot holes and pavement damage, particularly in shaded areas.

Ground frost acted to draw moisture from the ground which left the pavement saturated and subject to damage during the thaw, Imtech managing director Chris Gregory said.

"Unfortunately these conditions do occur periodically," Mr Gregory said.

Similar conditions were experienced in 1995 and 1998.

"As in previous years the difficulty we are facing now is that the weather and temperature does not enable the contractor to undertake permanent repairs," Mr Hawker said.

Compounding the problem was that traffic was ignoring signage to slow down in areas where repairs had been undertaken.

"At this point we are saying to our contractors to undertake the maximum effort to ensure that roads are safe but once again there is a fair amount of onus on drivers to slow down on damaged roads," Mr Hawker said.

The road conditions were not conducive to driving at speed. Temporary fill was being destroyed by speeding motorists, which in turn showered other cars with stones, scattering fill across the roads.

"People are putting themselves at risk of a tire blowout or other damage and also putting our road crews at risk, my advice is to slow down," Mr Hawker said.

Council's roading contractor Works Infrastructure had recruited additional experienced staff from outside the district to deal with the situation, Works Infrastructure Central Lakes manager Trevor Washington said.

"We currently have a number of crews undertaking temporary pavement repairs as the weather and temperature permits," Mr Washington said.

More intensive remedial work would take place as soon as temperatures would allow, he said.

Meanwhile the problems being experienced drew attention to the underlying design and construction of roads, Queenstown Lakes District Council chief executive Duncan Field said.

"We are about to receive an independent report which should allow us to make changes to how we build roads in the future. This should progressively eliminate these substantial and frustrating failures," Mr Field said.

ENDS

For further information please contact Chris Hawker or Duncan Field 03 441 0499 or Chris Gregory 03 442 2626 or Trevor Washington 03 440 2304.

By: Kiri