It is known that a water wheel powered the sawmill in its early years - but there is little documented information regarding it.
It was supplied from Ashcombe Water (and probably from the River Bale and Limecombe Water) with a millpond near what is now Boevey’s Restaurant.
An overhead launder/aqueduct brought water to the wheel.
In October 1897 the Land Agent told Frederick Knight that: “Waterwheel must be repaired or we shall not be able to use it this autumn for sawing or chaff cutting”
In February 1898 the Land Agent reported that “our machinery is not I fear strong enough for the work [cutting 40, 17 feet long 10” x 2” joists for the new West Cottages]. The saw and water wheel is working very well but I fear it would break down under the strain of cutting the joists.”
Later that month he suggested using the steam engine to power the mill as “one thing is quite certain, the present water wheel will not to any advantage cut timber“
The water wheel was replaced by a turbine in 1899.
Early reports suggested that the waterwheel might have been about 30feet in diameter. However, in June 2016 while constructing an improved car park at the sawmill members of the National Park Authoritiy's Field Services Team (Simon Lazarus and ?) unearthed what Graham Wills identifed as the ring gear/pinion from a ring-driven waterwheel. He sought the advice of millwright Martin Watts who estimated that it was from a wheel of about 20 – 24’ in diameter (+/- 4’ perhaps).
While the gear might not have come from the sawmill wheel but might just be have been dumped in the yard with some other material but if it was from the sawmill wheel Graham Wills calculated that if the launder supplying it came off the old leat at 316.9m, and was level, it would have been about 3.5 metres above ground level at the mill (or rather above the level of the existing footbridge). The footbridge is a bit above the level of the current sawmill floor (which is itself above the original earth floor) so, if the wheel was overshot and at ground level it couldn’t have been more than about 12’ diameter. If it was actually about 20’ in diameter it would have to have been breastshot, undershot, or sunk a few feet in the ground. The latter sounds reasonable and would still explain the long time it seems to have taken to sink the turbine tail race pit.
More work is needed to enable the operation of the waterwheel to be properly understood.