BBO were engaged as Transit New Zealand’s consultant throughout all stages of this project, involving extensive designation for SH1 and the South Island Main Trunk railway, from investigation through to construction surveillance. The project involved the realignment of 2.7km of SH1S and the construction of a new 270m long ten span two-lane bridge across the Awatere River, a new bridge passing the SIMT railway over SH1S. BBO’s role included survey, stakeholder consultation, designation and resource consent procurement, detailed design and construction contract administration. The old 325m long Awatere Bridge situated between Blenheim and Seddon in Malborough was built in 1901 and was one of three double-decker bridges in the country with trains on top and the road underneath. The new bridge, which runs parallel to the existing bridge, comes as a relief to locals and travellers as crossing the one-lane bridge was becoming more and more tiresome as time went on.
The bridge was designed using a proven and readily repeatable modular system, resulting in very cost effective and rapid construction. The cost per square metre is lower than similar bridges and no alternative tenders were received.
BBO engaged in a high level of consultation and value management with local authorities, iwi and adjacent landowners. BBO worked closely with stakeholders in the co-ordination of the design of a new rail over road bridge, in respect to permitted disruption to rail services during the construction phase, and with the contractor to manage haulage of earthworks from north to south of the river without delay to traffic.
BBO was recognised by Transit in May 2003 with a Certificate of Excellence for extensive alterations to designation for SH1 and the South Island Main Trunk railway and resource consents obtained with no negative submissions received and without Council hearing or appeals to the Environment Court. The project was completed under budget in October 2007, three months ahead of programme. It eliminates the only remaining combined rail and road bridge on SH1 and reportedly reduces travel times by up to 15 minutes.