Area’s ageing road bridges on agenda

The Scott Lane bridge over the Kyeburn River has sat broken since a portion of it was swept away...
The Scott Lane bridge over the Kyeburn River has sat broken since a portion of it was swept away by floodwaters last year.
The state of Central Otago’s ageing road bridges, and how to fix them came into focus at this week’s Central Otago District Council meeting.

Councillors were told addressing a funding shortfall to maintain and improve those bridges required both local and central government action.

To receive government funding, a robust local case has to be created before central government will consider providing suitable funds.

To clear that first hurdle the council has approved the development of a bridge strategy.

The strategy would include comprehensive details about the extent of the repair, maintenance and replacement work required to ensure the ongoing integrity of the district’s bridge network, councillors were told at their public meeting in Alexandra on Wednesday.

Council executive manager infrastructure services Julie Muir presented a report outlining the state of the bridges in the district.

"Like many councils across New Zealand, our region has an ageing bridge network," she said.

"This, combined with the impacts of climate change, earthquake risk, regulatory changes and increasing volumes of heavy vehicles, means many of our bridges will need to be replaced or undergo significant work over the next decade."

This would come as no surprise to locals who used the district’s bridges, she said.

"Council has committed to collecting the evidence required to support a robust investment application to Waka Kotahi in July 2023 for replacement and upgrading of substandard bridges.

"This will also inform community consultation regarding increasing community funding for bridge renewal work in the 2024 long-term plan."

The report included data collected from 187 structural inspections undertaken on Central Otago bridges between February 2021 and May by council and external engineers.

The key findings concluded that 109 bridges required no work or only minor maintenance; four bridges — at Scott Lane/Kyeburn River, Maniatoto Rd/Taieri River, McCunn Rd and Craigroy Rd — had been closed; and two bridges had been restricted to light vehicle access only (Linnburn Runs Rd and Nevis Rd Bridge/Stewarts Creek).

The Danseys Pass Rd/Kyeburn River Bridge would require a weight restriction assessment to be undertaken.

A further eight bridges were expected to require replacement in the next few years, 17 bridges required high-priority repairs and 37 bridges required special access to identify work required.

The report identified the bridges and some of the work that needed to be prioritised within the $1.45million of funding the council had available between 2022 and 2024, and provided recommendations on how the council could build a robust strategy to support its 2024-27 funding applications.

Roading activities received a 51% subsidy from Waka Kotahi NZ Transport Agency, the remaining 49% funded by ratepayers.

Waka Kotahi funding was allocated in three-yearly periods with the next round of funding due to start in 2024.