Site Records

Deanie Power Station - Interior

The underground machine hall of Deanie power station presented a considerably larger constructional challenge that had been anticipated, as the rock, initially thought to be sound, was discovered to be heavily fractured and kaolinised when excavation commenced. This required considerable rockbolting to stabilise, and it was not possible to leave the attractive bare rock walls seen at other underground stations.

Deanie is equipped with two 19MW Francis turbo-alternators of entirely conventional design. The machine hall excavation is 94ft long, 43ft wide, and 73ft high. The illustration below gives a good general layout of the station:

Entering the station from the access tunnel, looking left across the generating sets, the stairs to the turbine floor immediately in front:

Proceeding across the loading bay, looking across to the sets and control panels. Note carefully the ladder leading up into the roof of the station, from the yellow crane rail (top centre of image) - this is the start of the access tunnel to the downstream surge chamber, examined in detail on another page. It also serves to ventilate the station.

Looking down from the loading bay to the turbine floor:

Moving to the other end of the machine hall, looking back at the loading bay and access tunnel:.

Descending now to the turbine floor...

... then ascending to the crane rails for a birds-eye (well, bats-eye except they're blind as ba... oh hell you get the idea) view of the station:

This one is interesting - scan of an old negative I found, from a visit to the station many years ago. Compare with the pictures above, you will spot a few differences. Some of these may be due to the complete overhaul that was required after a major flood in, I believe, 1987. The entire tunnel system had been dewatered for maintenance. The manholes into the high-pressure system upstream from the MIVs were open. A gate on one of the sidestream intakes collapsed during a sudden spate, and the tunnel filled with water - which of course surged out through the open manholes and totally flooded the station.

Finally, one from the archives: Deanie under construction:

Words and images © 2003 Michael J. Ross