Counting cost of bridge repairs

The Kawarau Falls bridge last week after two weeks of repair work. Photo by Christina McDonald.
The Kawarau Falls bridge last week after two weeks of repair work. Photo by Christina McDonald.
Nearly half a million dollars has been spent in the past 10 years on repairs to the Kawarau Falls Bridge.

Most of the repairs were to replace the one-lane bridge's running boards.

The total includes $158,000 which was being spent on repairs that began at the start of last month and are due to be completed at the end of this month.

The running boards are the timber boards under the chip seal. They are what vehicles directly drive over.

About 35% of the boards are being replaced now.

New Zealand Transport Agency Otago senior network manager John Jarvis said the boards being replaced were more than 10 years old.

Some years there was no repair work but on average $49,000 was spent each year which Mr Jarvis said was ''quite normal'' for a timber deck bridge with a high level of traffic.

A new $18 million two-lane concrete bridge is on the cards, but not until after 2016.

Mr Jarvis said a concrete bridge would require significantly less maintenance.

Some damage to the timber bridge, which is part of State Highway 6, is caused by grit applied during winter to guard against black ice and other damage was through ''wear and tear''.

The repair work being being done now would mean a smoother drive and less rattle from the decking.

From March 6 the bridge has been shut between 11pm and 6am for the repairs, with only 10 minutes on the hour allowed for motorists to get across.

To minimise disruption the closure is from Sunday night to Friday morning.

Mr Jarvis said the work was on schedule to be completed by the end of the month, when the bridge would be open as usual in time for the busy winter season.

He said no significant repair work was planned for next year, although the agency would ''keep an eye'' on the bridge and it was possible minor work could be done.

''It's just like any other asset we have,'' he said, and added there was nothing structurally wrong with the bridge.

The planned new two-lane bridge has long been sought but would not be built until after 2016 and would take two years to construct.

Design and construction of the new bridge is included in the agency's 10-year state highway plan.

Mr Jarvis said a concrete bridge would likely only require resurfacing every 15 years and ultimately, should be ''very, very low maintenance''.

 


Maintenance costs

2005: No work.

2006: $99,300 spent. Replaced running boards, tightened bolts and repaired pier cap.

2007: No work.

2008: $42,200 spent. Replaced running boards, repaired wheel timber guards.

2009: No work.

2010: $150,000 spent. Replaced running boards, decking, asphalt and sealed.

2011: $30,000 spent. New bolting to running boards.

2012: $15,500 spent. New deck bolts, repaired walkway deck and handrail.

2013: No work.

2014: Spending $158,000. Replacing running boards and deck repairs.