Cost-effective and sound designs used elsewhere in Guyana could be implemented at D’Edward to stop erosion of the road

Dear Editor,

In an article titled, ‘D’Edward residents fear loss of road to erosion,’ which appeared in SN on May 19, it was reported that residents of D’Edward Village, West Coast Berbice said that the edges of a road alongside a canal close to the sluice are eroding, along with sections of the street, and called for urgent attention to these problems. Pictures were shown to attest to their claims.

I wrote a letter titled, ‘No operation manual available for sluice operator of major drainage facility at D’Edward,’ which was published in SN on May 23, 2008. In it, I drew attention to the problem which you reported upon and which had caused the sluice operator to keep the third door of the sluice permanently closed even during periods of heavy rainfall and high sluice discharge. His stated action was to slow the erosion process on the southern embankment/secondary road parapet before the adjacent roadway collapsed. Soon after my letter was published drawing attention to the ineffective operation and maintenance of this sluice and appurtenances, its operator was relieved of his duties.

In an invited comment as reported by SN of May 19, Mr Aubrey Charles, General Manager (GM) of the Mahaica Mahaicony Abary (MMA) Scheme which is responsible for this sluice, stated that he had only recently received reports about the erosion.

Something is amiss in Mr Charles’s comment, as he has been GM of the MMA for the past several years and regular reports on the operation and maintenance of the drainage, irrigation and flood control facilities within the MMA should have been compiled and reported to him at stated intervals. Therefore, it is incomprehensible that the GM was not aware earlier of the gradual erosion which was taking place on the façade drain abutting the D’Edward sluice within the MMA, unless this apparent lapse is a reflection of the years of unsatisfactory and ineffective management operations and maintenance of the MMA.

The Ministry of Agriculture (MOA) through the National Drainage and Irrigation Authority (NDIA) has been funding from loans, grants and tax payers’ dollars projects to improve drainage, irrigation and flood control to boost agriculture on the coastland. It is readily seen, however, that ineffectual management has seriously compromised the operational and monitoring procedures of MMA and indeed elsewhere, and this has resulted in a drastic reduction of benefits (such as assured drainage) the farmers were expecting to increase crop production on their farms, particularly in the MMA.

SN’s published photos show and my earlier inspection confirmed, that slips on the southern embankment of the façade drain abutting the sluice have been occurring for some time now because of scouring, particularly during the rainy season when the sluice is discharging flood water at its optimum capacity.

It is evident that the increased depth of the drain at this location has reduced the factor of safety of the southern embankment/road parapet, and under the influence of gravity segments of its slope are moving downwards and outwards into the drain. It is possible also that rainwater is finding its way into the underlying clay through cracks in the embankment and reducing its shearing resistance, thereby aggravating an already critical situation.

The GM has expressed the view that gabion baskets filled with stones will have to be installed to arrest erosion and slippage of the southern embankment. Gabion protection has been used to arrest scouring under certain conditions and circumstances, but it does not seem appropriate in this case, as stability of the embankment against scouring and slippages using gabions will be difficult to appraise with respect to its effectiveness, economy and safety.

Other cost effective and technically sound designs have been adopted to cope with problems of a similar nature in several parts of Guyana, and these should be examined and implemented to stabilize the embankment before the erosion creeps over to the Berbice River Bridge’s access road.

Yours faithfully,
Charles Sohan