Laying carbon foundations

Khalifa molded by coral calls

The construction of Khalifa Port in Abu Dhabi raised major environmental concerns because of a valuable coral reef near the port site. Bechtel played a leading role in protecting the coral reef, including creating 2D and 3D simulations on more than 150 configurations of the port footprint to determine the most environmentally benign location and layout.

The result was that the port footprint was moved 4.5 km and an access causeway was designed to maintain water flow and minimise the impact on nutrient flow, spawning patterns and water quality.
An environmental breakwater was built ahead of dredging, to reduce construction impacts, and temporary enclosed bund cells were used to isolate dredging activities.

“Precautions had to be taken to preserve the coral reef,” says Bechtel’s Marco Pluijm. “The 8 km environmental breakwater created a partition between the new port and the coral reef and in order to guarantee enough flow of fresh water every day, the port was connected with the shoreline by causeway.

“The priority was long-term sustainability of the coral reef during construction. If there had been any spill from the land reclamation, that spill would not have been able to reach the coral reef and deposit there. Long-term, if there was ever an oil spill or similar at the port, the breakwater will prevent it reaching the coral reef area behind it.”

The dredging contractors were required to implement an exemplar programme of seawater turbidity monitoring and there were regular coral reef health checks to confirm that no deterioration or loss of the nearly 30 different species occurred.

Abu Dhabi Ports Company received several environmental protection awards as a result of these efforts.