Cheap sand-filled tubes project help widen city foreshore

Dec 06, 2014 News

Government engineers are convinced that the use of special tubes along sections of the

Engineer, Amite Bauble points to an area that has improved with the installation of the geo-tubes.

city seawall have successfully created a wider foreshore area.
According to the Ministry of Public Works, post-installation surveys carried out on the geo-textile tubes along the Kingston/Kitty seawall indicated that the shoreline has improved with a much wider foreshore area.
Over a three month period – April to July – the Ministry installed six tubes to form a groined field. The project is an initiative under the 2014 Sea Defences Programme.
Amitab Babulal, one of the Ministry’s Sea Defence engineers who executed the project, explained that over the past few months, there have been significant sand deposits recorded on the foreshore area.
“The geo-textile tubes have contributed to beach stabilisation and the retention of shell/sand/sediment drifting in the westerly direction. In recent years, the sediments have been moving towards the Demerara River channel, which would pose a challenge to marine/maritime businesses and operators,” Babulal said.
Due to the success of the beach material retention, the Ministry is identifying other vulnerable sites to replicate the exercise.
According to Jermaine Braithwaite, a Senior Engineer, geo-textile tubes contribute to the long term shoreline management and promoting sustainable protection of the shoreline.
“Parts of Guyana’s shorelines have experienced erosion and overtopping due to the impact of high energy waves, and we have a rapid installation method that could help mitigate these adverse effects,” he added.
Areas under consideration include No. 63 Beach and sites on Leguan and Devonshire Castle, Essequibo.
The works at the seawall comprise of the installation of three geo-textile tube (geo-tube) groynes of 100 meters length with circumferences of 6.4 meters. Each groined was constructed by sand filling two 50 meters long geo-textile tubes which were installed with a butt joint interface to form a continuous unit along the design alignment for each groined.
Bauble also noted that the tubes have minimum impact on the environment and are low maintenance. “Gesture structures are also a cost-effective alternative when compared to traditional marine materials and methods. They are fabricated from a high–strength, specially engineered, woven textile with special high-strength seaming techniques to resist pressures during pumping operations,” he added.
The project would have special significance especially as Guyana’s coastlands are way below sea-level making the fight to keep the ocean out an uphill task. In recent years, there has been a marked increase in overtopping of the seawall during high tides.