KEY POINTS:
An end is in sight for the lengthy traffic jams Aucklanders face going to the Coromandel Peninsula on busy weekends, with Transit New Zealand today announcing plans to start building a new Kopu Bridge by mid-2011.
The 80-year-old, one-lane bridge on State Highway 25 near Thames carries an average 7700 vehicles a day, with many more at peak holiday periods.
In confirming plans to build a new two-lane bridge, Transit chief executive Rick van Barneveld also responded to concerns about the existing bridge's ability to withstand a moderate earthquake.
The bridge was closed one night last month for urgent maintenance of deck joints and Transit says on its website: "The existing bridge is an earthquake risk and sections could potentially collapse in a moderate earthquake".
But today Mr van Barneveld said the bridge was structurally sound and fit for the volume of traffic that used it.
"The bridge is safe. It was built in 1927 so it's not surprising that it doesn't meet modern design and construction standards. The driving force behind replacing it has always been to reduce traffic delays and deal with growing traffic volumes in years to come," he said.
He said it was important to put the information on Transit's website stating that sections of the bridge could collapse in a moderate earthquake in context.
Analysis had shown the Kopu Bridge was likely to withstand an earthquake of up to between one in 300 and one in 500 year magnitude, he said.
Although this wasn't in keeping with today's guidelines, which see bridges designed and constructed to withstand a one in 2500 year earthquake, the risk of such an earthquake was still quite low.
Mr van Barneveld said Transit had a robust bridge inspection programme and the bridge was continually monitored and maintained.
The new bridge is expected to take two to three years to build and Transit's latest State Highway Forecast puts the estimated cost in a $20 million to $100 million range.
- NZPA