Nelligen Bridge Replacement NSW



Client: Roads and Maritime Services NSW

Services: Independent Cost Estimator, Engaged to provide an integrated package of constructability and cost estimates for the concept design options through to the detailed design stage. This included bridge span options, staging options as well as construction and demolition costs. On the results of Concept Design phase works, we were successful in being awarded the constructability and cost estimation services for Detailed design through Cardno.

The integrated package services include;

  • Independent Cost Estimating
  • Risk Workshop and probabilistic modelling
  • Constructability Workshop Facilitation
  • Constructability Advisor

Project Cost: $250 Million

Time frame: 2015 – Project will be completed by 2020


The existing Nelligen Bridge was built in 1964 and forms part of the Kings Highway crossing of the Clyde River at Nelligen. During routine bridge inspections it was identified that some of the supporting concrete pillars under the bridge had deteriorated. The bridge has been assessed and is still able to safely carry normal traffic loads, however the pillars will weaken over time and the bridge will require significant future maintenance or replacement. Studies were required to determine whether it was better to repair or replace the bridge to allow a safe and reliable river crossing.


We provided first principle estimates and constructability reviews on 4 possible options. We also provided risk modelling and risk workshops to determine the safest options. Traffic management, bridge construction methodology and demolition of existing bridge were some of the main issues that needed to be addressed.


By providing the Roads and Maritime Services (RMS) with advice on cost, risk and constructability they were able to confidently proceed with the best option for their project. We then went on to work with design consultancy firm Cardno to provide cost, risk and constructability advice throughout the detailed design stage to ensure best for project results are achieved. With our construction experience, we were able to work closely with Cardo to improve construction staging, and develop an innovative solution for the cast in-situ western abutment and retaining structure which is constructed in the Clyde River.