Explaining the Waimea Community Dam’s Early Contractor Involvement process
TDC and WIL chose a new process to come to a final project cost estimate for the Waimea Community Dam that is robust and realistic. This process is called Early Contractor Involvement, or ECI.
ECI uses the skills and expertise of specialist contractors early on in a construction project to analyse all the activities involved and to reach agreement on the best way to complete the project. The process has been shown to save significant time and costs over a traditional tender process.
For example, the traditional process usually engages contractors after design has been completed. This often leads to delays during construction whilst design, methodology and materials are questioned and debated, often leading to design changes and increased costs.
In an ECI process, the final design will be completed after analyzing the detailed input from the contractors involved. They are advising their preferred construction methodology, plant and materials to achieve the most cost-effective solution.
ECI also includes working out the methodology, or how to build the dam in the most efficient way possible. Talking this through during early planning will result in a properly planned, structured, and no-surprises approach when construction begins. We can also identify the key issues involved with the build and the best ways to mitigate any risk.
Another positive outcome from an ECI process is that it brings together the design and construction team to use a creative approach toward reducing costs, time, and risk. This is called value-engineering and this process forecasts any issues that could arrive, attempts to solve these problems in advance where possible, and identifies and streamlines costs while ensuring the best possible quality final outcome.
As mentioned, the major contractors involved with the ECI are Fulton Hogan and Taylors Contracting whose team of designers and contractors have around 100 years of collective experience building dams in New Zealand and abroad. They work alongside the two fulltime equivalent staff in the Waimea Water project office.
How does the ECI add value to ratepayers?
One example will illustrate how the collective experience of the ECI team working together in advance of the project is already save time and money. In the area where the dam will be constructed, there are many types of rock material that will be re-used for the construction of the 400,000 m3 dam embankment, the spillway, the concrete plinth, the starter dam and the access roads. The project team does not want to bring in new rock for this project, it wants to re-use as much rock as possible for all of this new infrastructure.
So, before these elements of the dam were designed, the ECI team needed to understand what type of rock material and how much of it would be dug up during the excavation phase. The team analysed where they plan to dig, learned what type of rock it’s digging up, and has determined how best to extract and treat it so it can be used to meet the required engineering specifications for each of the dam’s elements. So far, the team is confident it can source most if not all of the rock required for the project from the ground it will excavate.
In the end, TDC, WIL, and the community will have a very robust construction estimate for the dam that is based on a collaborative, no-surprises process that is intended to provide the best value solution.