Hope channel the most suitable flood relief proposal in the circumstances

Dear Editor,

In the SN letter dated Feb. 6, 2009 Messrs. Alli and Ragwen implied that construction of the proposed Hope/ Dochfour Relief channel could worsen the flood problems of the East Demerara Water Conservancy (EDWC) rather than substantially reduce if not eliminate it.

The facts and circumstances available to resolve the underlying flooding problem of EDWC however, suggest otherwise.

The main flood relief for the EDWC is the 5-door Land of Canaan sluice and to a lesser extent the Cunha and Kofi sluices during such times when they are operational. These relief sluices are located at the western extremity of EDWC and discharge into the Demerara River.

At the eastern segment of the EDWC dam are the Maduni and Lama sluices which discharge their flood water into the Mahaica River usually with catastrophic consequences.

It is estimated that flood water from critical parts of the EDWC could take from 24-48 hours to reach any one of the relief sluices.

Hence the urgent need for a relief structure at this critical part of the EDWC to get rid of flood water quickly and in a safe and efficient manner before it reaches a dangerous level. It was this build-up of the conservancy level without responsive operational management to quickly relieve flood water to one or all the sluices which led to overtopping of the EDWC dam and caused extensive flooding of saturated coastal areas during the 2005 floods since the drainage system was not designed to cope with the additional volume of water suddenly thrust upon it.

The EDWC cannot continue with impunity its yearly flooding of homesteads along the banks of the Mahaica River from its indiscriminate dumping of flood water through the Maduni and Lama sluices. Often there is no choice because if the flood water is not released quickly the conservancy water level could breach its dam and cause catastrophic damage to the many villages along the coast, a more costly alternative than flooding the people of Mahaica.

Hence alternative means have to be found to relieve flood water from EDWC and with the available data and facts, the Hope relief channel was the most suitable flood relief proposal, given the circumstances and location.

I am of the view that critics of this project should direct their concerns not on the chosen method/location of flood relief but to ensure that the engineering works are undertaken by reputable consultants/contractors with proven track records to enable this complex project to be built to fulfill its objectives which have not been clearly stated.

Fortunately a start has been made but it is not very encouraging. The time given for bid submissions was too short resulting in only two bid submissions, one of which does not have the capability and should be disqualified. Therefore the Tender Board would be hard pressed to make an award based on one tender and a re-tender seems likely.

Engineers Alli, Ragwen, Seegobin and others have indicated many of the factors and parameters which have to be considered in the design of this project. In addition, EDWC will also have to take into consideration ancillary works such as strengthening and raising the conservancy dam as well as clearing the facade drain of silt and weeds to allow flood water to flow with no constraints quickly to the various relief outlets. These works will have to be undertaken simultaneously with channel construction so that an integrated conservancy relief system could function efficiently and effectively and thus make the annual fear of flooding a thing of the past.

Finally, EDWC should assure the people of Region 4 that it has the funds available to undertake this project since preliminary estimates suggest that it will be costly if designed and constructed to generally accepted standards to achieve the desired objectives.

Yours faithfully,
Charles Sohan

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