Bailey bridges are being used as temporary replacement for some bridges that were lost or damaged during the weather events of early 2023, and where a temporary bridge will help reconnect the community.
Site preparation is undertaken by the relevant local authority (or NZ Transport Agency for state highways), and Waka Kotahi is responsible for all bridge installations.
Bailey bridges are not always the best solution for every bridge that has been washed away or collapsed. There are a range of temporary solutions available in New Zealand, or a river may be able to be forded instead. If the site conditions are difficult, a solution further upstream or downstream may be better suited. In some cases, the best option may be to progress straight to a permanent solution, reinstating the bridge or culvert if resources permit.
The New Zealand Government acquired significant Bailey bridge stocks after the Second World War for use by the Ministry of Works. Custodianship of these stocks over time has transferred to Waka Kotahi. At the start of 2023, Waka Kotahi held around 20 Bailey bridges available for immediate deployment (with each bridge being 30m).
Waka Kotahi is looking to procure more stock, given the significant amount of stock that has been installed around the upper North Island across 2023 and early 2024. We are also investigating other temporary bridging solutions, to respond to the recovery phase of the cyclone and enhance our ability to respond to future events.
Waka Kotahi is reporting on Bailey bridge installation on the state highway network in the table below.
| Bridge name |
Road controlling authority |
Road name |
Status |
Bridge opening date |
|---|---|---|---|---|
|
SH35 Hikuwai No. 1 Bridge |
Waka Kotahi |
SH35 |
OPEN |
15 June 2023 |
|
SH2 Waikare River Bridge |
Waka Kotahi |
SH2/Napier-Wairoa Road |
OPEN |
14 May 2023 |
Councils updates can be found via the council websites below.
Timeframes for installation Whether Bailey bridges can be installed, and how quickly they can be set up, depends on how accessible the location is and how much work needs to be done to prepare the site. For example, sometimes piers (the support columns a bridge sits on) may need to be built to support the bridge, which can make installation take longer.
While establishing a Bailey bridge at a site can take as little as a few days for a short span, there could be weeks of site works involved prior to the Bailey being able to go in. There may need to be piers constructed, the surrounding roads rebuilt, or we need to wait for water levels to go down. Sometimes contractors cannot physically get the components to site until the surrounding roads are fixed. It’s important to note that sometimes installation may not occur till months after a need is identified.
Waka Kotahi manages a national supply of Bailey bridges and has a contract with Downer for the installation of the superstructure.
The road controlling authority is required to design and build the approaches and substructure for the bridge. These are typically undertaken by the authority’s design consultants and roading contractors.
Bailey bridges are generally designed to accommodate all road legal vehicles, not just light traffic, but on occasion they may have vehicle weight restrictions.
