2001 – Refurbishment of Diversion Gate No 2 Roxburgh Dam New Zealand

Thomas Zink, Michael Howat, Clive Anderson, Richard Davidson

This paper describes the refurbishment of Diversion Gate No 2 at Roxburgh Dam on the Clutha River, New Zealand. This 53m high concrete, gravity dam constructed in the 1950’s had three diversion gates fitted with stoney rollers which when opened into flow allows the rollers to disengage from the gate precluding subsequent closure. Diversion gate No. I was sealed off with a concrete plug. The remaining two diversion gates are required to provide additional flow control flexibility at the dam. Key aspects of the refurbishment design and construction include the system used to remove silt from upstream of the gate, and the condition of the gate itself and the concrete diversion channel after nearly fifty years of service. Brief details of the commissioning testing are also presented.