Overview of dam

Objectives of the Waimea Community Dam

The Waimea Community Dam is a significant local infrastructure project to augment the supply of water and add to the sustainability of the region. Objectives of the Waimea Community Dam are:

  1. Sufficient water at our homes all year round
  2. Healthy Lee and Waimea Rivers with abundant fish and flora where we can swim and play
  3. A robust economy from the success of the horticulture and farming industries
  4. Jobs for people in our primary industries and the support services working with them
  5. A better chance that families can maintain and grow their businesses for children and grandchildren
  6. Families staying and growing together in our community
Project phases

The project began in early March 2019 with site works to create access to the Lee Valley site. This was followed by the burying of a mauri stone, a mark of respect to Papa the earth mother and a blessing bestowed on the site and the structure that will be located there.

The second phase was the construction of the dam itself. The completed concrete-face rock fill dam is 53 metres-high, 220 metres-long, and 6-metres wide at the crest. About 490,000m3 of rock has been used to build the dam. The 165-metre-long spillway is complete.

The culvert was partially closed in mid-October 2022, so that the temporary river diversion pipework could be installed over the 2022/2023 summer. Commissioning of the temporary pipework was completed in autumn, and the culvert was closed on Friday 26 May so the reservoir could start filling in stages.

The Waimea Community Dam reservoir, named Te Kurawai o Pūhanga by Ngāti Koata, filled up naturally over several months. Then, on Sunday 21 January 2024, Te Kurawai o Pūhanga reached its full capacity and the spillway commenced flowing. This was a momentous milestone.

Final engineering analysis and verification of dam performance was completed in January 2024 and the dam and spillway were commissioned.  

Prior to rainfall capture reaching the top of Te Kurawai o Pūhanga in January, temporary facilities had been used to operate the dam from May 2023. As it filled through the latter half of 2023, engineers verified the dam’s performance at ‘hold points.’ Water was also released through this time to ensure river levels were above the required minimum flow. 

The temporary pipes and facilities were removed in February so the Contractor could complete the final hook up of the permanent pipework. 

On Saturday 2 March 2024, water from the reservoir was released through the smaller of three permanent dispersing valves that release water from the reservoir in dry periods.   

Successful testing of the two larger dispersing valves in early April meant the Waimea Community Dam was operational from 10 April, 2024, followed by its final commissioning. 

Te Kurawai o Pūhanga contains approximately 13 billion litres of water.

WWL’s responsibilities

WWL is responsible for constructing Nelson Tasman region’s newest dam. This includes:

  • resource consent compliance
  • land and access rights transfer and management
  • health and safety compliance and assurance
  • environmental compliance and assurance
  • optimisation of sustainability opportunities
  • community and stakeholder engagement
  • management of contracts required to complete the contracts, including construction, design assurance and cost assurance.

The project was divided into a series of workstreams and the team structure was amended progressively to match the evolving requirements of the project through its lifecycle through to ‘business as normal’ operation.

Click on the image below to enlarge.