Dear Editor,
In a letter by Mr Philip Allsopp captioned “If the pattern of erosion is studied it is possible to predict where it will occur and plan maintenance accordingly” (08.04.08) he implied that Mr Malcolm Alli whom he did not identify in his letter but whose letters he referred to in Stabroek News stated that he seems to misunderstand the behavioural pattern of erosion on the Guyana Coast. He further stated that ‘if the problem of coastal management is tackled intelligently and continuously there is no cause for alarm.’
Mr Allsopp is of the opinion that if the coastal cyclic phenomenon of erosion and accretion is identified and studied it is possible to pinpoint coastal areas of erosion and plan effective maintenance accordingly. These statements are all well and good, but in recent years the government has failed to provide the resources, manpower and equipment, needed to collect the relevant data to make this possible.
The existing scant data available makes it difficult to predict accurately when and where erosion will affect the sea defences since this depends on a number of unknown variables such as the width of the tidal flats, the type of material making up the foreshore, the intensity of wave action and the direction of wave attacks. Moreover, the general pattern is disturbed near the mouth of the rivers by local currents and by local deposition of riverain silt and sand. Similarly, man made (Demerara Harbour Bridge) or natural obstructions to tidal and other currents can and have caused unexplained local erosions (Craig, EBD), which is almost as severe as the cyclic attack but which may stop as unpredictably as it began. Therefore, Mr Alli quite rightly understands the problem and grave concerns about the impending disaster that lurking erosion could inflict on those people living in exposed areas.
Mr Allsopp stated that during this tenure as Chief Works and Hydraulics Officer in the 1960’s his staff was able to predict when and where erosion would have occurred and planned effective maintenance accordingly. If this was so why were there breaches of the sea defences at Bladenhall, Lusignan and elsewhere in the 1960’s?
Mr Allsopp felt that Mr Alli’s claim that the cycle of erosion of 40 years along the Guyana Coast was wrong and that his figure of 38 years was more correct. The Hydraulics Laboratory, Delft stated in their Demerara Coastal Investigations (1960-61) that the cycle is about three times a century. The World Bank states that the interval is 30 years while the Netherlands Engineering Consultants (NEDECO) in their Report on the Sea Defences in 1972 stated that the cycle was somewhere between 20-40 years. Is it possible that Mr Allsopp has data to support his pronouncement?
Finally, Mr Alli is a Structural Engineer by education and early training. Later in his career and during his employment with the government of Guyana he was involved not only in building designs but those for bridges, sluices, culverts and sea defences. Among his major achievements were design and supervision of construction of the cultural centre, MMA sluice damming the Abary River and various elements of sea defences on the East and West Coast of Demerara and the Essequibo Coast. He is no ding-a-ling but someone who has made a substantial contribution to various civil engineering projects in Guyana. Contrary to Mr Allsopp’s assertions, Mr Alli was not required as a prior condition to undertake studies to design and construct sea defences, Mr Alli’s education and training equipped him with the basic knowledge and understanding of other civil engineering disciplines such as soil mechanics, hydraulics and construction means and methods etc. to design various engineering structures with confidence.
If any of the projects, sea defence or otherwise, which, Mr Alli designed showed technical evidence of incompetence, then Mr Allsopp should have had the courage to point it out in his letter since this would have supported his claim that Mr Alli’s technical understanding of sea defence problems were incomplete.
As a parting jab Mr Allsopp claims that Mr Alli in his letters “fabricated history to omit the achievements of his contemporaries and disregard their tutelage in a specialty which was not wholly familiar to him”. As a colleague who worked with Mr Alli for many years I was flabbergasted by this statement since I cannot recall any Guyanese engineer in the 60’s and early 70’s who fully understood the hydraulics and morphology of the phenomena occurring along the Guyanese coastline, let alone stability of the embankments to prepare sea defence designs adequate to withstand the forces necessary to protect the coastland. Many of their designs were based on erroneous concepts such as building rigid concrete structures on a flexible embankment. Mr Alli’s real contemporaries, as Mr Allsopp should know, are the Dutch.
Yours faithfully,
Charles Sohan
