Dear Editor,
A report in SN of April 9 with an accompanying photo showed a collapsed river defence masonry wall at Louisiana, Leguan which according to the Government Information Agency (GINA) failed during the spring tide of Friday, April 6. The evidence suggests otherwise, as the problem did not occur overnight since there was a gradual foundation failure of the rigid masonry slope due to excessive settlement and tilt.
The flexible clay embankment on which the masonry slope was cast, compressed over time, causing the masonry slope to move and tilt eastwards into the river under wave action and seepage, because there was no toe protection of the masonry slope by a sheeted cut-off wall capped with a concrete beam and braced laterally with boulder stones or gabions to resist lateral movement.
This is another example of poor design and lack of maintenance of the river defence on the island, and to make a bad situation worse, the wooden revetment under construction behind the failed masonry structure intended to arrest further creeping of the embankment into the river also shows signs of failure and poor workmanship. Further, the temporary works being undertaken will not prevent future high tides from overtopping the embankment and flooding the villagers.
The Sea Defence Board with its executing agency, the Ministry of Public Works, has a statutory responsible for sea and river defence works along the entire coastland. It is this ministry which is supposed to have the relevant experience and competence to deal with issues relating to river defence breaches in Leguan and elsewhere, and not the Ministry of Agriculture/ National Drainage and Irrigation Authority (MoA/ NDIA) which reportedly is involved in sealing the breach, as they do not have the experience and technical capability to contain flooding and make repairs when breaches occur along the coast.
Therefore, it is incomprehensible that the MoA/NDIA with many urgent outstanding drainage and irrigation problems to address within its competence continues to be side-tracked into the unknown.
As an analogy, it is worth noting that the Ministry of Local Government with no experience in stelling construction was the contracting agency for the failed Supenaam Stelling which eventually had to be taken over by T&HD, Ministry of Public Works for completion.
The people of Leguan are fed up with the makeshift efforts by the government to provide them with a stable and secure river defence system, as breaches have been occurring along their eastern coastline at regular intervals with severe losses to crops and livestock. As a matter of urgency, the Ministry of Public Works should start rebuilding adequately designed sections of the river defence structures which have collapsed to prevent further tidal inundation of the villages, and not wait for the passing of the National Budget in Parliament before rehab work starts. The ongoing mismatch of temporary works will not arrest or solve the underlying sea defence problems of Leguan.
Yours faithfully,
Charles Sohan
