Dear Editor,

In an article which appeared in the SN of November 13 about Norwegian officials touring the conservancy, the writer stated, “One of the imminent projects is to build an outfall channel at Hope that will be of enough capacity to relieve the pressure on the conservancy.”

A recently completed Ministry of Agriculture (MoA)/National Drainage and Irrigation Authority sponsored Engineering Design Study for the East Demerara Water Conservancy (EDWC) Northern Relief Structure at Hope/ Dochfour, essentially concluded that the risk of the conservancy overtopping its embankment would increase with the completion of this proposed structure and closure of the existing Lama and Maduni sluices respectively. If the proposed project is to be executed as outlined, its high initial capital costs for six major structures, a relief channel 11 km long with a 30m base width plus a 3 km long deep foreshore discharge outlet, will be difficult to finance. Added to these capital costs is the expenditure for maintenance of the proposed outfall channel which is still to be determined and could be costly. Therefore, this proposed project with its questionable costly design to safely relieve peak conservancy floodwaters during periods of heavy rainfall is seriously flawed and should be going nowhere.

It is apparent that the MoA realizes this and is exploring an alternative – the possibility of a Flagstaff-Mahaica relief route, which, if technically and economically feasible, would have significantly lower investment and maintenance costs than the Hope/Dochfour deep foreshore channel option to relieve floodwaters from the EDWC. However, Residents of Region 4 should not expect to see any major construction works with respect to flood relief for the EDWC any time soon as further detailed investigations have to be carried out, a project formulated and funding obtained for its design and construction.

Finally, President Jagdeo at a recent press conference stated that funds will be made available for mangrove cultivation to protect Guyana’s foreshore and to arrest soil erosion there. In the late 1940s, the Public Works Department with responsibility for sea and river defences, did extensive trials planting mangroves to protect and arrest erosion along selected locations of the foreshore on the Island of Leguan and probably elsewhere.

Experiments were also carried out on a black sage/bamboo combination strapped together to form a matting, which was then placed over the sloping clay embankment of the river defence system to protect it from erosion. Both these experiments failed to produce the desired effects, and reports on the causes for these failures should be in the records of the Ministry of Public Works and Communications.

My recollection is that fishermen, vandals and foraging animals played havoc with the young planted mangroves destroying most of them in a short period of time for varied reasons, as the plants struggled to grow and stabilize foreshore erosion in the brackish water of the Essequibo River. With respect to the matting system, the vegetal composition of this could not withstand the pounding of waves generated by the NE trade winds at high tide levels. Hence, the system quickly disintegrated exposing the clay slopes to wave attack and erosion, although subsequently protective action was taken by the construction of concrete/boulder grouted revetments as could be seen at Canefield, Belfield and elsewhere in Leguan.

It is unwise therefore to spend money resuscitating seemingly failed experimental coastal erosion projects. Rather, sea and river defence works of a more permanent and stable nature which have stood the test of time should be the objective to protect Guyana’s coastline from the constant threat of erosion.

Yours faithfully,
Charles Sohan