Guyana should not be experimenting with geotextile structures for coastal protection as their effectiveness has not been recognised

Dear Editor,

It was announced by the Ministry of Agriculture (MoA) that BK International (BKI)
has been awarded a $26M contract for construction of a geotextile structure at Victoria on the ECD. It was stated also that BKI was tasked with constructing another geotextile structure close to the head regulator for the proposed Hope Canal on the East Demerara Conser-vancy. There was no public tendering for the supply of materials and construction of either of these projects.

Geotextile structures have never been constructed in Guyana and their use as the Minister of Agriculture claims is experimental and intended to provide information as to their suitability for further use locally and internationally. Therefore their application to reduce wave action and hence arrest coastal erosion in mangrove growing areas in Guyana is yet to be proven as an effective alternative to existing coastal structures such as sea walls. Minister Ramsammy should further clarify how the restoration and protection of mangrove forests will contribute to the social and economic development of Guyana.

Guyana is a poor country and its limited technical and financial resources should not have been used to experiment with geotextile structures for coastal protection as their effectiveness for this purpose has not been recognised here or elsewhere.

Instead the available funds should have used where they are most needed: to shore-up the crumbling sea and river defences in populated areas which have been neglected for want of maintenance for many years now, by using tried and proven methods.

Mangroves flourish in certain ecosystems and environmental conditions such as riverain areas with little or no wave action, but not in areas exposed to the fury of the Atlantic Ocean. The next cycle of erosion now moving along the Guyana coast from east to west will    certainly expose the fallacy of the mangrove programme as a low-cost alternative to quell wave action and thus arrest coastal erosion to protect the villages.

Building dikes to effectively protect the eroding coastline from 8 ft waves should have been the preferred method but it does not come cheap.

The geotextile structure being built by BKI close to the proposed head regulator on the Hope Canal poses some challenging problems which if not addressed could be catastrophic. The soil conditions at this location are much more complex than at the Victoria site as there are extensive depths of pegasse – a material of poor shear strength and high porosity on which the structure is being built. Site conditions suggests that the contractor will no doubt be unable to dig out this material and replace it with a suitable fill of the desired strength to accommodate the geotextile structure because of the exorbitant cost of doing so. Therefore it is not inconceivable that a blow-out of the proposed structure due to inadequate design and construction, hydraulic pressure and poor frictional resistance of the soil on which it is being built is a possibility, particularly when the water in the canal is at operational level. Such a breach could cause considerable flooding and property damage to the adjoining villages, and it is hoped that the MoA will have contingency plans in place to deal with any eventuality.

Finally, it will give considerable solace to sceptical Guyanese if the Minister of Agriculture, as he claimed, could state categorically the amount (Kgs) of peppers and condiments (type) which the many single mothers have produced to date on the mangrove forest land under development at Victoria. Also, the quantity (litres) of honey which the promoters of the mangrove re-planting project claim they have harvested from the newly planted mangrove trees to date.

Yours faithfully,
Charles Sohan