See & Do

'The Waterwheel' is a central and iconic landmark of Warburton, where it operates at the site of The Waterwheel Visitor Infomation Centre on the main street. This Waterwheel is a replica based on the original McVeigh's Waterwheel.

Prior to 1908 a 4.3 metre wheel was used to power a generator to provide electrical lighting at the Contention gold mine in Contention Gully about 10 kilometres south of the Upper Yarra Dam.

In 1908 it was moved seven kilometres to Patti McVeigh’s Hotel, the site of which is now under water. Thought initially to have been used to drive a chaff-cutter, it subsequently generated electricty for hotel lighting. About 1.6 kilometres of water race was cut through rock to bring water from the Yarra River for both power and hotel use. The original generator at the hotel produced only 110 volts and in 1922 the proprietor Mr Frank Seymour replaced it with a larger generator.

In 1936 McVeigh’s Hotel was lost to fire but the Waterwheel survived. The hotel was rebuilt and although both it and the wheel survived the 1939 fires only the Waterwheel was left standing after the fires one year later.

The Melbourne and Metropolitan Board of Works purchased the property and for a time the wheel was used to provide power to a nearby surveyor’s camp.

Prior to the commencement of the filling of the Upper Yarra Dam in the fifties, the wheel was dismantled and stored in the MMBW’s salvage yard for 30 odd years.

In 1978 it was restored by the Board of Works. Some of the original ironwork was used and an old photograph was used as a reference to ensure an accurate reconstruction.

McVeigh’s Water Wheel was installed in its present position in the picnic grounds at the Upper Yarra Dam together with a 44 metre long timber water-race. The wheel is still in working condition today.

The replicated Water Wheel support at the Visitor Centre has the following inscription: “Water wheels similar to this were an important part of the history of the Warburton area. They powered gold mines and provided energy for saw mills, houses and commercial properties.”

Fast Facts – Design: K. Pert, Construction: Eastern TAFE (Building & Construction Department) and K. Pert Funding: Seventh Day Adventist Community, Timber: Yellow Stringybark Size: 6 metre diameter.

**ABOUT WATERWHEELS**

A Waterwheel consists of a wheel mounted on a horizontal shaft, able to rotate on bearings, with containers or "buckets" fixed to the outer rim of the wheel. When filled with water at the top of the wheel, the full buckets on one side of the wheel exceed the weight of the empty buckets on the other side and cause the wheel to rotate. The full buckets spill out water at the bottom of the wheel as it rotates, and empty buckets are refilled as they reach the top of the wheel. The power obtained from the revolving wheel can be used to drive machinery such as battery stamps, pumps or other equipment.

**THE MECHANICS** of operation are interesting as they tell us more about the characteristics of the wheel.

Rotation of the wheel is comparatively slow - about ten revolutions per minute (RPM) but because of the large diameter of the wheel, (6 metres), the speed of the outer rim is quite high. (10x 6 x pi x 60 / 1000= 11.3km/hr). For SAFETY reasons stand well back from the wheel while it is revolving.

The speed of rotation is dependent upon the amount of water entering the buckets, the friction of the bearings and the amount of work being done by the wheel.

Consider the stationary ("locked rotor") forces acting on the wheel. Each bucket is filled with up to 20 litres of water. At the furthest point, the bucket is 3 metres from the axis of rotation and the turning moment is the product of the mass and the distance. Other buckets, depending on their position around the wheel, are at lesser distances from the axis and so their turning moment is correspondingly less. The lower buckets are spilling out their water and so have a lesser turning moment due to both a lesser distance and a reduced amount of water. Despite these factors, it would be possible to calculate an overall turning moment due to the effect of the water in a locked rotor condition.

But there is another complication. As the wheel begins to turn, the mass of water exerts a lesser force on the bucket. Imagine the wheel to be turning at a speed which approximates the free fall velocity of water (say halfway down the wheel - this can be easily calculated from Newton'sv squared formula). At this point, the water would exert zero force on the bottom of the bucket. This, then becomes the limiting speed of the wheel which in this case is 27 km/hr or 24 RPM so no matter how much water is poured into the buckets, the ultimate speed of the wheel will not exceed this. The water, incidentally, comes under another force, that of centrifugal force due to rotation but this does not significantly alter the speed.

One way of calculating the power which could be obtained from the wheel is to multiply the quantity of water (20 litres x 36 buckets x 10RPM) by the height moved (6 metres) by the pre established efficiency for a waterwheel (about 60%) and convert this to kilowatts or horsepower. The maximum output for this wheel would be approximately 4.5 kW or 6 HP.

So, understanding the mechanics of operation, we can determine that a waterwheel will operate best with water filling the buckets but rotating at a "slow" speed with appropriate gearing or pulley drives to obtain a desired equipment speed which, preferably, should have a steady load.

The Warburton Waterwheel is an example of the type of motive power used by the pioneers who mined for gold in Warburton in the early days.