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Technical data

Capacity - total

 2200 m

Capacity - inner cell  1100 m
Capacity - outer cell  1100 m

Number of Cells:


Depth of water

9 metres

Top water level (m AOD)

124 metres

Ground Level (m AOD):

95 metres

Year Of Construction

1993 - 1994

Inlet Pipe:

250mm diameter

Outlet Pipe

250mm diameter


300mm diameter

Structural design

Pearson Ellis Partnership.

Main contractor

Norwest Holst Ltd

Description of the Tower

General: The tower is a reinforced concrete structure throughout. It has a conical bowl shape and is divided into two compartments by one internal cylindrical wall. The tank is supported on a central access shaft and on 12 radial raking columns. The tank floor and walls were designed as a water retaining concrete structure without any lining.

Walls: The tank's external sloping circular wall is 350mm thick. It is in the form of an inverted cone and has an inside bottom diameter of 14.26m and an inside top diameter of 23.2m. The external face of the wall has pre-cast concrete cladding panels, with a dark exposed aggregate finish between the feature column supports.

Internal Divisional Wall. The circular internal wall is 350mm thick and is vertical.

Central access Shaft Through the Tank. The wall is 300mm thick and the internal diameter of the shaft is 4.0m.

Roof: The tower roof is supported on the central access shaft, the dividing wall and the tank external wall. The 200mm thick slab has a 150mm fall towards the central access shaft. Rainwater drains to two outlets located over the central shaft. The surface of the roof is asphalted and dressed with granite chippings. A double rail handrail is provided around the perimeter of the roof.

Access To Roof:  A spiral steel stairway inside of the shaft gives access the roof and water tanks.

Floor: The tank floor is 450mm thick and has a 100mm slope towards the central access shaft.

Shaft: Main Central Access Shaft. The central access shaft has an internal diameter of 3.7m, except through the tank where it is 4m diameter.

Foundations: The tower shaft and columns sit on a 16.4m diameter, 2m deep pile cap which in turn is founded on 60 piles, each 600mm diameter.

Lagoon: Just to the north-west of the tower is a drainage lagoon. This has been provided to store water discharged from the tower overflow, tank washout pipes, or rainwater from the roof. A 300mm diameter concrete overflow pipe from the tower feeds into the lagoon. Water is slowly discharged from the lagoon through a concrete outlet/overflow structure to an adjacent ditch.

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