Hume Dam Wall Movement
| About this Item |
Speakers | Glachan Mr Ian |
Business | Private Members Statements |
HUME DAM WALL MOVEMENT
Mr GLACHAN (Albury) [10.19]: Today I shall make a few remarks about the Hume Dam and the Murray River, which have been in the national news recently. I have concerns about some things that have occurred. Some time ago the Murray-Darling Basin Commission and its officers learnt that there were problems at a bend in the earth-filled wall of the Hume Dam and that faults had developed in the wall, which was moving slowly down river because of the weight of the water behind it. The work that was undertaken to repair and strengthen that section of wall highlighted the need to look at other sections of the wall. Technical experts constantly monitor every section of the wall and know exactly what is happening with it at any given time. They keep a close watch on it and regularly consult experts around the world.
Recently it was found that the joint between the main concrete wall, the spillway, and the relatively narrow concrete curtain wall, that is, the core wall in the centre of the earth-filled embankment, was beginning to leak. When the dam was constructed many years ago the dovetail joint between the narrow core wall and the main concrete spillway was filled with pitch. As the years went by the pitch deteriorated and a leak developed. It was decided that concrete grouting would be forced into the joint to stop the leak. The result of the leaking was that the toe of the earth wall downstream adjacent to the spillway was weakened and needed repair work. When the concrete grout was forced into the joint it was noted that the core wall moved five millimetres in one day - and that was the extent of the movement that generally occurred in 12 months. It must be remembered that the wall is flexible and moves continually, and movement itself is not a need for concern.
I emphasise that the technical experts say - and I accept their view - that the dam is perfectly safe and always will be, providing it is properly maintained. When the work was completed it was discovered that the training wall, which keeps the spillway water from washing away the earthen bank downstream of the spillway, needed strengthening and that material adjacent to the training wall and downstream of the core wall needed replacement. I emphasise that the dam is safe, but this work needs to be done as soon as possible to ensure that it is made as safe as is possible. An extra load needs to be put on the toe of the earthen wall to support the core wall. To achieve that extra level of safety, the authority has decided that it must reduce the level of water in the dam by two metres immediately and by five metres over a period to take the load off the wall so that some of that material can be removed.
The unwanted consequence of the work was flooding down river. A huge flood in the Murray River downstream of the dam has caused enormous problems for individuals, businesses and farmers. It must be remembered that farmland is not simply inundated with water and that farmers must find extra feed for their stock. Water lying on the land for a long period has a long-term effect: it destroys the pasture, which takes a long time to rejuvenate. Farmers in the area are concerned that they will lose a lot of money. I appeal to the Minister to use his influence with the commission to arrange compensation for the farmers as quickly as possible to help them to feed their stock and move them to agistment, and then to compensate the farmers for the long-term losses that they will experience. Normally the farmers would have to sue the commission individually for compensation. I hope that the red tape can be cut and that some way can be found to compensate the farmers as quickly as possible. The commission's officers would like to be able to help the farmers. I assure honourable members that the farmers are desperate. They need help, and I appeal to the Minister to assist them.