Business South Dec / Jan 2022

34 | to page 36 Downer - Tekapo Improving scheme’s seismic safety Kim Newth REGIONAL DEVELOPMENT A unique engineering project in the Mackenzie Country, completed in 2021, has dramatically improved the seismic safety of Tekapo’s hydro-power scheme. Downer NZ recently took top honours at the 2021 CCNZ Construction Excellence Awards as the project’s lead contractor. There is no doubt that the seismic risk is real. New Zealand’s Alpine Fault has the potential to cause a major quake within the next 50 years, (NZ GNS advice). Genesis Energy, New Zealand’s largest energy retailer, recognised that risk in investing $17.7 million in the Downer-led project to construct and install a new Tekapo A intake gate. As Downer’s project manager Alex Mowe explains, the new 50 tonne gate has been designed to close in the event of an earthquake and cut-off uncontrolled flow from Lake Tekapo which potentially could lead to downstream flooding via the hydro-power scheme. Whereas existing gates (stop logs) on the lake can only be shut if there is no flow, the new gate delivers an effective shut-off mechanism in Tekapo A power station’s intake tunnel which can carry up to 130 cumecs (m³/sec) of water. “The new gate has three seismometers that pick up seismic vibrations triggered in an earthquake allowing the gate to close automatically. The gate would also self-close if power supply was interrupted,” he says. Proud to provide support to Downer and Genesis Energy for the Tekapo A intake gate project 43 Cresswell St, Dunedin | 03 477 5892 | Design | Fabrication | Machining | Sheetmetal Processing | Site Works SITE SERVICES 30-36 Treneglos Street, Washdyke, Timaru • NDA Services are specialists in design, fabrication and installation of dairy and water processing equipment, including mechanical installation, process pipework, backed up by a well experienced nationwide team. NDA Services were proud to support the Downers Tekapo project. BRINGING STEEL TO LIFE Proud to Supply & service hydraulic equipment for Downer ONE STOP SHOP FOR HYDRAULIC DESIGN, MANUFACTURE, BUILD, PARTS & SERVICE. 0508 497 732 34 Birmingham Drive, Christchurch