A worsening drought in the northern South Island has seen the newly built Waimea Community Dam – in the hills behind Nelson – is doing what it was designed to do for the first time.
Waimea Water Ltd (WWL) recently started releasing water from the reservoir to augment the flows in the rivers and aquifers of the Waimea Plains, in response to continuing dry and warm summer conditions.
The company says water from the reservoir was released on March 2, through the first and smallest of three permanent dispersing valves. Water had earlier been released via the spillway, when unexpectedly high summer rainfall inflows brought the reservoir, known as Te Kurawai o Pūhanga, up to full capacity in late January.
Since then, a lack of rainfall has seen the water flow reduce significantly, while work continued towards completing the permanent pipework.
WWL chief executive Mike Scott said that he expects the two larger dispersing valves to be operational within the next two weeks.
“The smaller fixed cone valve has increased flow into the Lee River at a time when it is severely needed.”
Scott says the flow will be curtailed for periods over the next few days as some works were completed, but the valve would run close to capacity otherwise. “Once the other two dispersing valves are operational and their performance verified, the dam will be fully commissioned. Commissioning is scheduled for later in March.”
Waimea Irrigators Ltd chair Murray King says irrigators had been looking forward to this day all summer.
“It is a great feeling to know that Waimea Water can now control the release of water from the reservoir, when it is needed, and it is certainly needed now. The current dry situation and water restrictions show how much the community needs the dam.”
Tasman Mayor Tim King said it was “bloody great” to see the water flowing.
“It has been a quarter of a century in the making, but this weekend we have an operational dam to supply the region with much needed water supply for the next 100 years.”
