Residents of Wallers Delight on the West Coast of Demerara are now free from saltwater intrusion as more than 800 meters of riprap sea-defence works have been completed.
The project, which commenced in November 2017, was completed in three phases. BK International has executed 300 and 260 meters respectively of riprap sea-defence in two phases and Toolsie Persaud Construction completed another 300 meters.
Speaking with the Department of Public Information (DPI) Ministry of Public Infrastructure’s Project Coordinator, Dennis Ramsingh said the works were critical due to the rapid degradation of the mangrove trees over the years.
“Had government not taken the intervention to construct riprap sea-defences then there would have been lots of damage and breaches of the embankment. That would have caused inundation to immediate residential agricultural land. But because we were monitoring the area over some time, we had seen the need to take this intervention early,” Ramsingh explained.
The final phase of the project was delayed due to challenges with a regular supply of sand for the work. Also, construction was delayed due to the removal of decayed mangrove trees before the commencement of excavation works.
The project entailed excavation of the seaward slope to construct the slope and toe and the riprap structures which involved excavation, sand filling, placement of geotextile fabric, underlayer and the armour stone which is the finished structure. Ramsingh pointed out that similar works were also completed at Windsor Forest.
“Works were identified at this area (Windsor Forest) because we had aged concrete sea-defences with low crest elevation which contributed to severe overtopping during peak spring tide period. The ministry took the initiative to replace that aged concrete structure with 300 meters of riprap sea-defences,” the Project’s Coordinator underlined.
The project was completed ahead of schedule and entailed excavation of the foreshore, to construct the toe and lower slope, sand filling to construct the upper slope, crest and embankment works were also included.
According to Ramsingh, these riprap structures, which are built of rock or other material used to protect shorelines, require less maintenance and are flexible. Most of the materials for riprap’s construction is also available locally.
Additionally, the areas in Den Amstel, Uitvlugt and Leonora that were flooded earlier in the year due to severe overtopping will also see improvement. Ramsingh indicated that the ministry has already prepared the designs, contracts have been awarded and physical work will commence shortly. These will also be executed in phases.
By: Ranetta La Fleur.
Images by: Jules Gibson.
