RIPRAP Sea defences in Guyana

Mar 27, 2024 Letters

Dear Editor,

As a Guyanese retired professional that loves his country, sir, I would like to bring to your attention a matter that could have serious implications for Guyana’s future development and the lives of Guyanese on the coastline.

Firstly, in the Sunday Chronicle newspapers (5th February 2024), there were no less than 30 RipRap tenders for various sizes of projects across the coastline of Guyana totaling a sum of 4.2 billion Guyana dollars. Tenders are open on the 8th of February and close on the 29th of this month. Sir, this is significant given the fact that there was a recent breach of a RIPRAP sea defence structure in Corentyne Berbice in January of 2024. The ministry came out with an explanation but as an engineer that has seen the site the explanation does not match the level of erosion that has taken place. This breach followed on the heels of the Mahaicony breach in 1999 that swamped farmlands, homes and businesses and cost the government billions, the people in this area are still reeling to this day from this incident.

Sir, you have to sometimes be very careful of what is told to you, for a much larger cover-up could be taking place, and I believe it is happening in this case. Geotextiles or Geosynthetics are foundation materials that are ENGINEERED for specific applications, meaning an engineer designs a structure and chooses a specific geotextile based on the mechanical and hydraulic factors that must be maintained for decades. It should be noted that no two Geotextile manufacturers produce the exact Geotextile fabrics with the same specifications. The main purpose of the geotextile in RIPRAP is to withstand the constant pounding of the Atlantic Ocean, providing drainage and stopping erosion of the soil behind the structure, so that a collapse or breach does not occur. Guyana’s EU-funded RIPRAP sea defence projects started in 1996 and based on our soil mechanics, wave action, weight of boulders etc. a Geotextile was chosen, this geotextile had been used until 2017 without a single collapse or breach occurring. From 2017 to now, contractors had decided that they wanted to use Geotextile materials out of China, mainly because it was cheaper, it was also not certified and 3rd and 4th grade yarns used to produce them, this type of quality is specifically done to sell in developing countries where no checks or standards are verified.

At the same time, it should be noted that the tender documents to this day are still using the same specifications for the geotextile that is no longer being used in the RIPRAP structures. The price also remains the same and also the same estimated cost was used even though a much cheaper geotextile was being used. So of course, Guyana’s SPECIALLY SELECTED CONTRACTING companies were able to make much more profits for these projects while at the same time putting the entire Guyanese Nation at risk.

Guyana is already 6ft. below sea level and scientists have warned that it is still sinking along the coastline. There is cause and effect to everything we do in life that is basic human knowledge, the rapid development of our coastline is putting more weight and strain on the Guyana coastline. Also areas that were once permeable are now impermeable due to buildings so our lack of a proper drainage is further compounded. Our drainage trenches are now being converted to much smaller concrete drains, so while Guyana is speeding along with development it is done in a haphazard manner, this along with poor materials and workmanship and no maintenance, will ensure this beautification will not last very long, but once it can fill the pockets of a few it will continue. Look at the level of water at kokers at high tide and see they are up to the brim with water, so Guyana is already on the precipice on a major disaster. The 2005 floods were just a warning to Guyana to get its act together with respect to flood prevention, preparation and response, look at all the pump station contracts and see the number that is not even close to starting and monies paid out, all these issues are greatly increasing our problem, Guyana is at the edge of disaster with respect to its coastline defense strategy, it is a matter of when not if it will happen, and all Guyanese will suffer to some level and degree.

The Chinese are able to produce a cheaper geotextile because the use of 3rd or 4th Grade yarns and their geotextiles are untested or uncertified, while they would sell the low-grade geotextiles to 3rd world countries, these geotextiles would not be allowed to enter a developed country because these materials would have to be tested and certified before they can enter the country. With Guyana’s soft clayey soil conditions and more areas needing soil engineering, the proliferation of uncertified, untested geotextiles from any country would not help Guyana in building the next Singapore or Dubai, those countries have construction standards that are strong and not to be messed with by anyone because they are building for the long-term, no country cannot keep rebuilding infrastructure every five years and paying lawsuits and become a first world country. Guyana urgently needs to invest in a lab for Geosynthetics, so that when a Tender has specific specifications for a geotextile, the contractor can get his geotextile tested and certified by the lab, and the materials on site have to be checked to ensure it is in compliance with the engineer requirements. This will ensure our capital projects are getting the materials specified by the project engineer, who has designed the structure based on the specifications of the geotextile, capital structures will then have a longer life span with minimal maintenance, and the country can use its resources on new projects instead of rebuilding recently built structures.

This short-term mindset and culture must be crushed for Guyana to see its true potential, believe me, contractors will still make a hefty profit and become the billionaires they want to be, Guyana at the same time must build its country on a solid foundation and geotextiles are a part of that foundation.

With the recent breach in Berbice or the one in Mahaicony in 1999 if the geotextiles were tested to check its compliance with the Tender documents, it would not have been approved for use. With these Chinese geotextiles in dozens of RIPRAP structures along the coast of Guyana, it is a sitting time bomb for the Nation, in my estimation, there will be much more breaches that will happen, that can literally cost the Government trillions. Since all one has to do is file a class action lawsuit and get the geotextile tested to compare it with the specifications stated in the Tender document and they will not match.

Engineers in Guyana seem to have lost their power of oversight with contractors, and that is most unfortunate for the future of the fastest growing economy. I am not advocating for any geotextile company, my interest is in using the right geotextile as specified in the Tender, with what is happening now the government and the Guyanese people are left exposed quite literally at all levels using these geotextiles. The Chinese are quite capable in the manufacturing of quality geotextiles to sell to developed countries. However, they just like to take advantage of vulnerable developing nations with no way of testing and checking the quality of the geotextile material they sell. The mechanical properties such as tensile strength, elongation and static puncture also the hydraulic properties such as water permeability and characteristic opening.

In the tenders are different from the Chinese Geotextiles being used. So, the specifications of the Chinese Geotextiles are not in compliance with the Tender documents, for instance the water permeability is very important since it has to do with drainage, the pores in the Chinese geotextile are not the same as specified in the Tender, this will lead to it clogging faster creating a blockage for water to pass through, thereby causing more strain on the structure and the eventual collapse or breach of the structure. When you look at various geotextile materials, they can look very similar, however when it is tested, the results could be strikingly different.

The Geotextile is used to stop the erosion of the soil, provide drainage, withstand the heavy boulders placed on it and stand up for decades against the constant pounding of the Atlantic Ocean. With Guyana’s coastline being over 90% of its economic activity and population, including farmlands, aquifers, residents, and new infrastructure being added every day, protecting its coastline should be a top priority, there is so much profit for contractors building RipRap sea defences, why risk the prosperity of Guyana with untested Geotextiles?

Some important points:

It is recommended that stitching machines be used to strengthen the seams of the overlapped geotextile, if contractors were to invest in this simple machine, it will literally strengthen seams and pay for itself in the first project since they would not have to overlap the seam 3ft as recommended for a proper seam, the Chinese Geotextile roll is around 8ft wide so to overlap 3ft feet is impossible, with this not being done, it is a very big problem for the long-term stability of the structure.

Guyana needs to invest in a testing lab for Geotextiles just like you are having more concrete labs now, since the use of geotextiles will significantly increase due to Guyana’s soft clay soil type and its rapid development more areas will be encountered that will need foundational reinforcement using geotextiles. All geotextiles used in Guyana RIPRAP sea defence structures must be certified and independently tested and comply with Tender specifications. Guyana is set to be the next Dubai, but does not have a building code in place.

Regards,

Mr. D. Brooks

Retired Engineer

incident, individuals, Mr. D. Brooks, Retired Engineer, RIPRAP

Latest News