Porirua High Level Reservoir No. 2

Article written by: Arno Louw – Senior Civil Engineer

Vitruvius was engaged as part of a Design and Build collaboration with Holmes and HEB to deliver the mechanical design for a 9 megalitre Porirua High Level Reservoir No. 2. This project plays a critical role in supporting water infrastructure for growth, resilience and operational efficiency for the region.

Our scope included the mechanical design of the valve chamber to the reservoir systems, ensuring robust and efficient operation under varying conditions. In addition, Vitruvius developed the automation framework and functional descriptions to enable seamless integration of control systems, providing reliability and ease of operation for the client.

A key complexity addressed in the design was the seismic resilience requirement. The mechanical design incorporated flexible overflow pipework and seismic jointing to accommodate >500 mm axial and lateral movements under Ultimate Limit State (ULS) conditions. This was achieved through careful consideration of seismic couplers and flexible pipework.