During the same outage, a confined space, rope access, corrosion and coatings inspection was carried out in the penstocks, which was completed in 8 days.

Due to the high profile and pressure of the job, the crack team of Martin Wilson and Rich Turner were brought it for this very occasion. This was the first recorded inspection since the penstocks were built.

The Cobb Valley is New Zealand’s highest pressure hydroscheme, with 600m of head flowing down two 2.5km, wrought iron and mild steel riveted penstocks, internally coated with coal tar epoxy.

Abseil Access were contracted to provide confined space rescue, access, corrosion inspections and to provide a full report detailing the current condition of the coatings.


A recent project at Christchurch International Airport saw us dangling from the control tower having a close look at the decorative spiral mesh and associated steel supports.

This was one of the first installations of this incredibly versatile Kaynemaile product, which needed some minor adjustments since the earthquakes of 2010 and 2011.

Thanks to Kayne and Jason at Kaynemail for providing technical information and grappling claws.

Photo by Mark Watson