In mid-May, inspection with a remotely operated vehicle (an underwater drone) found two leaks in the impounded supply liner. These were located at the base of the western embankment of the dam wall and required repairs to manage the risk of dam failure and/or disruption to Dannevirke’s water supply.
The recent repair operation was the result of a team effort which involved careful preparations and planning, as no known examples of a similar operation have previously been carried out in New Zealand. The dives took place underneath the cover and to simulate these conditions, the repair mission was practiced in a shipping container full of water to imitate the darkness under which the repairs took place. Roger Earp, Acting Three Waters Manager, who has overseen the operation is wrapped with the outcome of these temporary repairs. “We have reduced loss of water from the dam by around 80% which is a great result. We are also now in a much better position to understand what needs to be done to permanently remedy the current challenges with Dannevirke’s impounded water supply.” The permanent fix will require emptying the dam. Before this happens, Council needs to assess the various options, taking into account factors such as cost, timeframes, and cultural considerations. Most importantly, before the permanent repairs can begin, water security measures need to be in place to ensure a secure water supply to Dannevirke.
Council would like to encourage Dannevirke residents to come to the public meeting on Tues. 27 June for more information on the temporary repairs, and to discuss the critical decisions that have to be made with regards to a permanent fix for the impounded water supply.
Date: Tuesday, 27 June, Time: 6:30pm – 7:30pm
Venue: Dannevirke, The Hub, Allardice Street