Woodville Impounded Water Supply
Woodville’s water supply is a matter of importance to both the residents of Woodville and Tararua District Council. Work is underway with three main goals: increase the volume of clean water stored, reduce the load on the water treatment plant and reduce the number of total water bans.
The current water supply struggles to keep up with demand for fresh water when the river is low. Part of the problem is that the Woodville dam is shaped like a teardrop on its’ side. This design can contribute to increased sludge levels, adding to the clay problems of the existing dam - these problems can result in water that needs intense treatment to make it safe, and the current backwash cleansing process can lose up to 30% of the water it is treating. Add hot dry weather to the equation, and the dam is often unable to keep up with demand.
Adopted as part of the Long Term Plan, work to solve this includes changing the shape and lining of the dam, reducing the amount of clay suspended in the water, and restricting how much water goes to users outside of the town boundaries.
Increasing the volume of the current dam, where the earth wall and outlet structures had to remain as-is, meant hours of surveying by drone, underwater measurements, and manual labour. The best cost option involves changing the sides of the dam and adding a flexible welded lining.
Before works can start, we will be applying for the required building consent from Environment Waikato. Once the consent has been granted, excavation to change the dam walls can start later in 2016.
The third step will be allocation. This means "sharing out" the water to ensure that there is enough for everyone during peak flow times including households and businesses in town, and farms or commercial enterprises outside the Woodville township. Farms and commercial properties will also be encouraged to fit water tanks. This will ensure that, in summer - when their need for water is at its highest - their water demands can be met from their tanks, (topped up by Council supply).
Tararua District Council is pleased to have this enormous project underway.