Oakura Water Treatment Plant Upgrade Project

The Oakura Water Treatment Plant (WTP) currently supplies the Oakura township with potable water by treating raw water extracted from bores. The plant treats raw water by dosing with sodium hypochlorite and lime before discharging to two reservoirs and distributing to the township. The plant is owned and operated by the New Plymouth District Council (NPDC).

As a result of water contamination in Havelock North in 2016, new Drinking-water Standards for New Zealand are on the horizon that will help prevent occurrence of a similar incident. Various studies and assessments were commissioned by NPDC in 2018 to review the situation at Oakura WTP and to provide recommendations on projects needed to bring Oakura WTP operations up to current best practice before these requirements become mandatory under updated Drinking-water Standards.

The Oakura WTP requires upgrades to allow the plant to treat the bore water to 5 log protozoa removal. The upgrades will align the WTP with the anticipated DWSNZ requirements and best practice (Six Principles of Drinking Water Safety).

The outputs of the project are as follows:

•  Install a duty/standby cartridge filtration system
•  Install a duty/standby Ultraviolet (UV) disinfection system
•  Install the associated piping and valves to allow more automated remote operation of the plant
•  Replace the Sodium Hypochlorite system with an onsite 1% Sodium Hypochlorite generator
•  Upgrade the loading facilities to allow for safe delivery and offloading of chemicals and equipment.
•  All associated mechanical, instrumentation, electrical and controls work.

The key objectives of this procurement are:

1.  Optimise the Constructability of the Works
2.  Collaboration between all parties
3.  Proactive HSE Risk Management
4.  Quality Management
5.  Proactive Risk Management
6.  Value for money

Critical factors for a successful project are:

•  Completing the works avoiding negative affects to downstream users.
•  Collaboration with NPDC (Client) and WSP (Designers / Supervisor)
•  Constructability enhancements to the design
•  Whole of life cost savings / Value for money
•  Zero HSE incidents/ accidents
•  Zero Defects Post Completion Date
•  Total of the prices less than the Target Cost.
•  Completion of the project by the accepted completion date.

The Project Scope in Volume 2 provides further detail and the requirements of the works.

A key aspect to the success of this project relates to the high degree of planning and coordination that will be involved for each mechanical tie-in.

This project provides the right Contractor an ability to collaborate with NPDC and WSP Consultants to benefit the local community through using a NEC4 Option C Construction Contract. The design phase of the project is well developed with multiple design reviews, SID and HAZOP already completed with NPDC operations, external consultants and designers.

The Request for Tender (RFT) process will use the Price Quality Method (PQM) for tender evaluations. Price Quality Method (PQM) is designed to evaluate tenders when the quality of the supplier is very important, and the Client is prepared to pay more for that quality.
The contract will be an NEC4 Option C, Target Cost Contract, with X21 (whole of life cost proposals).

The benefit of target cost is the ability to align the objectives of the parties, which helps to create a partnering environment. The Contractor and Client are both encouraged to work together to control costs, sharing the risk of over or under spend through the gain-share/pain-share mechanism. The open book approach helps to build trust between the parties, through the sharing of sensitive information by the Contractor and the visibility to NPDC of the true cost of the project to the Contractor.

NPDC have also chosen a "main option C" contract to promote collaboration and performance as the Contractor will be working on live plant. Secondary option, X21, allows the Contractor to propose design modifications (Scope changes) to provide savings to the whole of life cost for the Client.

The Contractor will be engaged to complete a constructability review of the design with Client to identify any potential whole of life cost savings, construction efficiencies, and proposals to achieve best quality and HSE outcomes.

NPDC are ideally looking for a Contractor that has expertise in working in live water treatment plants or similar process installations withstringent compliance requirements.