Dear Editor,
Earlier this month, Minister of Agriculture, Dr Ramsammy gave December 31 as the revised completion date for the Hope-Dochfour Canal Project (HCP) when flood waters from the East Demerara Water Conservancy (EDWC) could be safely discharged into the Atlantic Ocean.
An eight-door sluice (one of the components of HCP) across the sea defence will control discharge from the canal into the ocean, but a review of its design shows a number of anomalies which if not corrected will affect the proper functioning of this structure, and hence compromise the design objectives of HCP.
The sluice gates are to be remotely controlled by electric motors with power supplied by GPL and two standby generators in case of emergency, although it is difficult to understand the justification for two instead of one generator in the circumstances. Further, once the gates are opened there is no mechanism showing how they will be closed. It is reasonable to assume therefore that the weight of the gates will exceed the friction forces and hydraulic pressures acting on them at the time of closure, allowing the gates to close freely under gravity. If for whatever reason the electric motors fail to activate the gates there is no mechanism to indicate as to how the gates will be opened and closed manually or otherwise, particularly at a time when EDWC is in flood mode.
When closed the gates will rest on steel plates fastened on top of the weirs. Design experience has shown that unless an approved sealant strip is fastened to either the bottom of the gates or on top of the plates of the weirs, severe leakages are to be expected between the two steel surfaces at closure.
As with any structure, regular maintenance, repairs or in cases of emergency the sluice will have to be shut down and de-watered to carry out work on any of these. Unfortunately no provision for stop logs or a similar isolation mechanism has been provided for in the design to de-water critical parts of the sluice to facilitate work of any kind in the dry.
It is hoped that due attention will be given to these issues before construction of the sluice is completed to enable the structure to function effectively.
Yours faithfully,
Charles Sohan
