JABEL HAFEET POND FOR STORM WATER NETWORK PROJECT IN AL AIN

M/s. Abu Dhabi General Services Company PJSC (Musanada), on behalf of the M/s. Abu Dhabi Housing Authority (ADHA) appointed M/s. CORE Engineering Consultancy LLC to do a detailed design of External Storm and Irrigation Connection to Jebel Hafeet and Ain Al Faydah Developments. Accordingly, the designer proposed concept design options of stormwater discharge ponds strategy to the relevant project stakeholders, which mainly involved the construction of two massive ponds within Ain Al Fayda & Jabel Hafeet locations, near to the ongoing Emirati Housing Development project. The size of the pond is significant due to the large volume of stormwater expected from a 1 in 25 years storm as well as from groundwater recharge. The proposed Jabel Hafeet pond is rectangular with dimensions 250m x 75m (length x width). The pond design was to be done entirely as a trench by excavating 6m from the existing ground level. Since the original groundwater level is approximately 3m below the current ground level at the pond location and that the total wall height is 6m, the lining solution has a pivotal role of allowing groundwater recharge into the pool without developing pore water pressure within the backfill side. However, the original tender answer was a Segmental block reinforced soil wall system, which is ineffective due to the lack of flexibility and porosity of its facia.

Being the pioneer for hydraulic works with double twisted wire mesh products, the contractor approached Maccaferri Middle East to propose a suitable reinforced soil wall solution for the pond bank lining. Maccaferri proposal was to replace the segmental block reinforced soil wall with Terramesh system and ParaGrid geogrid. Both Terramesh and Paragrid are BBA (British Board of Agreement) certified construction materials. The drainage requirement of the wall was managed without adopting AASHTO # 57 aggregate as backfill; thanks to the flexible and porous stone-filled gabion face of the Terramesh system. Maccaferri was involved in design, supply and site assistance of the project. The installation began in January 2019 and completed in July 2019.