Dear Editor,

I refer to the article, ‘A survey launch would allow monitoring of coastal erosion’ based on an interview with engineer Philip Allsopp with comments by engineer Charles Sohan (SN, April 27, 2008)
Your readers may find these facts interesting as a clarification to Mr Sohan’s comments.
Hydrographic data on Guyana was used by Delph Hydraulics in 1962 to create what was called the TxD diagram, ie Time versus Distance of the different fathom lines along the East Coast. The TxD diagram started with data from 1935 and ended about the 1980s. Hydrography reportedly started in Guyana in 1935, after breaks in the East Coast, Nog Eens sea defences, where hundreds of feet of sea wall were deposited several feet landward. The posts of the sluices can still be seen now in the ocean standing like sentinels.

These diagrams informed the Sea Defence Engineer where to expect that the sea would be bombarding the defences, so he could strengthen the existing walls or build dams if the area allowed it, such as was done in the Strathspey area.

There were two hydrographic sections – Sea Defences and Transport. One was responsible for coastal work and the other for navigation in Guyana (then British Guiana) and they had several survey launches. Some of these were Sir Frederick (56′) built in the UK in 1949, Critchlow (60′) built by Sprostons in 1961, and the Lanaballi bought from the USA in the late 1960s, which did coastal work. The launches Boxer (50′) and Renew (75′) – UK built – did navigation work. None of these vessels exists today.

‘Sling-mud’ was unknown outside Guyana in the ’60s but the same phenomenon is now called ‘fluid mud’ by the Europeans after the Port of Rotterdam started to experience the problem in the 1980s.
It would be nice if the authorities re-established the hydrographic sections and set up a research team including personnel such as a botanist, agriculturalist, geographer, hydrographer, etc, who could tell us why the Courida trees are dying. On a stable bank there are healthy Courida trees, but during the erosion cycle the Courida dies. If the Courida trees remained Guyana could save millions of dollars annually.

Yours faithfully,
RI Choo-Shee-Nam