We refer to Mr Seegobin’s letter (‘Risk analysis study for conservancy relief absolutely needed,’ SN 24.2.09) on the Hope Canal Project and recommend that he forward his concerns to the Government of Guyana for a risk analysis of the conservancy dikes and flooding which should be carried out.
In SN dated 24.2.09 the Minister of Agriculture stated that modelling for the conservancy was earlier carried out by a British and a Dutch company and they recommended that Hope is the acceptable location. Earlier in another article he stated that the water depth was higher at the Hope end and was lower at Land of Canaan end, hence the decision to locate the canal at Hope. He also said it was not necessary to fix the Land of Canaan Sluice (LOC) and canal to drain the conservancy more efficiently as recommended by one of the writers in an earlier letter. Another consultant is presently undertaking a further study of the conservancy costing some US$3.8M.
As experienced engineers who both worked in drainage and irrigation and sea defence sectors including the conservancy for a number of years, we are surprised at the approach adopted. Study after study is being carried out, yet the inherent core problem of the conservancy is not being fully addressed and there has not been any published report of the studies undertaken so far.
The canal size we mentioned in our letter was a preliminary example we roughly designed based on the 2000 cusecs capacity of the LOC relief canal. This was merely to give a perspective of the scale the hydraulic works contemplated.
We reiterate our position that unless this Hope Canal is designed to work 24 hours a day and can operate as such it will eventually become a white elephant.
It should also be noted, the discharge outlet sluice for the Hope Canal would be located through a section of the existing coastal sea wall that is over 80 years old. No proper sea defence alignment has been worked out for this area. Maintaining the existing wall during a future severe coastal erosion cycle is doubtful. We recognize that the risk and hydraulic uncertainty is very high and becomes the main limitation of constructing a major discharge structure through the existing sea wall.
Malcolm Alli P Eng
Michael Ragwen P Eng