Putting Operators First: Insights from Waiāri's Design Journey

R Clark (Tauranga City Council) & S Pearson (Beca)

Tauranga City Council (TCC) commissioned its new Waiāri Water Treatment Plant (WTP), with water first being delivered to customers in December 2022. The WTP has a 30 ML/d capacity with a future design capacity of 60 ML/d using coagulation, clarification, membrane filtration and disinfection (sodium hypochlorite). The WTP is also a zero liquid discharge facility with all liquids either recycled or physically removed from site, a process rarely used in New Zealand. The WTP design had a strong emphasis on putting the operator first by considering health and safety, operations team visibility and movements, segregation of visitors, plant and chemical areas, maintenance activities and site tours. This approach, led to a facility where the operations team have a modern working environment, excellent visibility and control of areas, and a reduced need for PPE.

This paper outlines the collaborative approach to the design of the Waiāri WTP by TCC and Beca to provide a safe and operable facility. This paper discusses the key factors to success through the design process including:
• Creation of facility design principles before pen was put to paper, as a rule book for designers
• Bringing in operations experience and requirements early
• The value of visiting other sites with the operations team and learning from others experience.
• Understanding core operational tasks, and health and safety to inform design and layouts.
• Understanding and applying resilience from the operations teams’ experience to manage expectations of a water supplier.
• Considering and segregating chemicals
• Managing noise and heat
• The value of traditional safety in design and HAZOP processes
• The use of 3D design and virtual reality for design reviews
• The value of a 3D model during construction

This paper then discusses the operational and maintenance context on how the design thinking has carried through into an operational facility, including:
• The safety of reduced noise: Hearing protection not required, except for specific areas (centrifuge and generator buildings)
• Reduced PPE requirements in operational areas compared to TCC’s existing WTPs.
• A site where access and maintenance of equipment can be completed from ground level or an adjacent scissor lift.
• Reducing confined spaces and ladders to a minimum
• Clear access ways for maintenance
• Clear sight lines from key operational facilities
• Separation of plant and visitor areas

The result of this process has resulted in a safe and operable facility in an operator-centric layout that can be applied to future facility layouts where the operations teams’ safety, security and control of visitors and contractors is improved.