PECULIAR PROBLEMS DELAY KAIMATA REPAIR PROJECT

Greymouth Evening Star, 16 February 1950, Page 5

PECULIAR PROBLEMS DELAY KAIMATA REPAIR PROJECT

Peculiar difficulties are being encountered in the work of repairing the tunnel at the Kaimata hydro station, where growing leakages have resulted in the closing of the station for at least a month. The work started this week. Because echoes and reverberations have made impossible the mixing of concrete in the tunnel itself, this work has to be carried on outside the tunnel. The mixture is sent down a chute to the tunnel mouth and then taken by wheelbarrow to the site of the work, considerably complicating what normally would be a simple task. The noise of the mixing machine would be considerably magnified in the half-mile long tunnel, creating a din which would be nerve-racking in the extreme for workmen. To get a comparatively dry bottom for the work of placing a new cement surface, a sand-bag barrier or dam is erected close to the section on which work is planned. As the water reaches the top of the temporary dam it is taken across the work-area in a wooden flume. After the treated area is given time to harden, the dam is moved on to allow another part of the tunnel to be repaired. This somewhat tedious arrangement also adds to the length of time required for the repair job. About 15 men, including Ministry of Works and State Hydro Department workers, are employed on the repair project, which as yet, is still only in its first stages.