An important milestone has been reached in the completion of the Waimea Community Dam project, with all consent, and Tasman Resource Management Plan (TRMP) requirements related to the dam’s commissioning now met.
This means that from Monday 16 September, 2024, the dam is deemed fully operational, and we can begin to provide the anticipated benefits to urban and consented water users across the Waimea Plains.
For those who have advocated for or contributed to the dam’s construction, reaching this stage is the culmination of many years’ effort to secure the water supply and maintain increased flow to the Lee and Waimea Rivers.
Steps required from the consent holder Waimea Water Limited to complete the official commissioning process included the full testing and certifying of the mechanical and electrical control components of the dam.
This ensured the dam is handed over from the contractors as a full and complete project.
A claim made by the joint venture (JV) contractor, under the Construction Contracts Act, has been successful. The result of the adjudication was an increase in the estimated Cost to Complete (CTC) for the overall project to $207.5 million.
The dam is one of the region's most important infrastructure projects and the largest dam built in New Zealand for over 20 years.
With a maximum capacity of about 13 million cubic metres, the size of the dam’s reservoir - Te Kurawai o Pūhanga - mitigates the impact of a drought greater than a 1:50 year event.
The flow from the dam will support horticulture water takes from bores on the Plains and also the community water supply bores near Appleby that supply water to the combined Richmond / Nelson water supply network .
The areas of Māpua, Ruby Bay, Brightwater and Wakefield also use bore supplies from the Waimea Plains, which benefits from the recharged aquifers.
Assisted recharge of the aquifers maintains water levels for extraction and reduces the risk of saltwater intrusion from the coast and also maintaining higher river flows in the Wairoa/Waimea Rivers which also improves river health.
Water has already been flowing from the dam through the smaller dispersing valve since Saturday 2 March 2024, supplementing the flow over the spillway. This combined flow averted the severe water restrictions many in the District were placed under during this period.
For both affiliated and unaffiliated resource consent holders, the commissioning is also important as it means ‘Fully Operational WCD’ conditions applicable to the respective consents come into force.
Resource consent holders affected by the new conditions have been written to, advising of the important changes coming up.
It is recommended that consent holders take the opportunity to review their consent conditions applicable from 16 September 2024 to understand what this means for them going forward, particularly around water take volumes, rationing and cease take requirements.