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Gloucester Docks &
the Sharpness Canal


Water Pumping at Gloucester

To supplement the natural streams that flow into the canal, pumps at Gloucester raise water from the River Severn to replace that lost through operation of the locks, evaporation and abstraction. This page outlines how the pumping equipment has been improved in recent years, based on information provided by British Waterways staff during a Heritage Open Day visit in 2009.

No 1 Pump
     The main pump used prior to 2001 is now preserved on the West Quay near to the small dry dock. It has inlet and outlet pipes 48 inches in diameter and a discharge valve with a stroke of 45 inches. When driven by an electric motor, it could supply 3.4 million gallons per hour (15.4 ML/hr). It was installed in a new building, approximately on its present site in 1962-63 at a time when there was a need to provide more water to make up that being extrated from the canal at Purton to supply drinking water to Bristol. It needed to be primed and started by an operator on site, but it could be shut down automatically by a timer.

No 2 Pump
     Also used prior to 2001 is an older pump in the pumping engine house on the other side of the small dry dock. This also has inlet and outlet pipes 48 inches in diameter, but it has a less powerful motor and so it is only capable of supplying 2.8 million gallons per hour. It was installed in 1945 to replace an earlier steam driven pump in the same building. It had to be primed, started and shut down by an operator on site. Although not used for many years, it is retained as an emergency stand-by.

Four New Pumps
     In 2000-01, four new electrically driven pumps were installed in a chamber under the West Quay, and new inlets from the River Severn were constructed across Severn Rd beyond the fence in the background. The pumps can be started and stopped by the touch of a button in the adjoining building, or these operations can be controlled from a remote laptop computer. The monitoring of canal water level measurements is now done electronically, and the results can be used to control the operation of the pumps automatically.

Water Intake
      Water is extracted from the River Severn via eight inlet valves in a compound between Severn Rd and the river. There is generally much silt in the water, and this can be seen spreading across the basin when the pumps are operating. When the tide reverses the current in the river, the water carries particularly high levels of silt, and so pumping is avoided during these periods.


     Thanks are due to David Viner, Ashley Ellis and Wayne Jones of British Waterways.

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