Created out of rock and sea sand, the islands are an extraordinary man-made creation. The islands consist of a five kilometre long ‘trunk’ and 17 ‘palm fronds,’ protected by a half-moon shaped wave break. Work on the project began in 2001. The creation of the palm islands has resulted in ground conditions of sand coral and limestone. Contractor Al Naboodah Engineering Services chose HDD and microtunnelling to install pipes and services between the ‘fronds’.
A Herrenknecht AVN D2500AH was a part of the team on the island of Jumeirah, drilling two safety tunnels of around 600 metres in length for various supply lines such as electricity, telephone and water, which run in a slight curve from one of the palm branches to the protective ring. The AVND bored 600 metres at a diameter of 3,025 mm. The cutterhead power is 316 kW with 1,200 kNm torque.
The Palm Jumeirah project also included twelve HDD bores with a total length of 9,600 metres, 500 mm diameter PE pipe. The rig was a Vermeer D300 x 500 with 136 tonne pullback, 68,000 Nm torque. Also in use were three Vermeer R300 fluid recycling units.