Ruakura Reservoir was delivered to a tight timeline to meet the commercial needs of key stakeholders. WSP accelerated the preloading phase and earthworks design (ahead of the main construction contract) to make sure a suitable platform onsite was available to the construction contractor to begin construction. WSP also reduced the carbon footprint and costs of the project, by recycling onsite surplus material.
The WSP structural team provided options on seismic resistance, longevity and cost to deliver the reservoir to an IL4 standard. This was based on a design life of 50 years and durability of 100 years,using a post tensioned structural system. WSP’s mechanical design incorporated a staged manifold design using split case pumps,which achieved the required flow flexibility and saved approximately $500,000 in capital costs.
LIST OF PRIMARY SERVICES
WSP provided a broad range of design services for the reservoirs, which followed all best industrial practices and standards, and relevant regulatory requirements.
- verifying the scope of works and timelines, and planning and programming the design process
- Assessing and identifying information gaps
- Facilitating and documenting workshops with HCC
- Developing cost estimates at key stages
Completing investigations needed to inform design, including geotechnical investigation, survey and service identification.
WSP also designed two 12ML identical, circular, above-ground post-tensioned water reservoirs, to importance Level 4, as well as:
- two 650mm ID bulkmains which connected to the existing bulkmains located in Wairere Drive and Peachgrove Road
- one reservoir pumphouse, to Importance Level 3 and located on-site, which allowed for one reservoir to operate, and provided for the second reservoir to be added later
- associated services, including on-site permanent Emergency Power Generation to 80% of maximum demand and a trunk main, electrical and control system.
WSP’s project management team maintained a local Hamilton representative as key contact to manage the process and provide regular project updates.
The construction programme for construction was accelerated as the preload (a critical part of any reservoir construction) was staged ahead of the main contract. The design could be duplicated and staged onsite to cater for growth, while giving the city more robust water storage in case of an emergency event. WSP’s staged design catered for the growth of the new development area and had the flexibility to deal with industrial demands, while realising capital cost savings in excess of $500,000.
This will be Hamilton's first reservoir with IL4 seismic resistance.