Entrant: Arcadis

Project owner: Muharraq STP Company BSC(C)

Developer: Bahrain Ministry of Works

EPC contractor: Samsung Engineering

Consultant: Arcadis

Architect: Arcadis

Financiers: Samsung Engineering, United Utilities and Invest AD

Given its rapid population growth and strong economic performance, Bahrain has a pressing need for additional wastewater treatment capacity.

The Muharraq sewage treatment plant (STP) and sewer conveyance system was planned to serve the present and future needs of the residents of the country’s third-largest city. Its completion provided an adequate sewerage collection and conveyance network, new sewage treatment facilities and a new deep-sea outfall.

The project is located in the busy Muharraq Island, where the buildings have cultural heritage value but little or no foundations, limiting their structural integrity. The road corridors in this urban area already contain multiple underground utility services.

This required a huge effort in traffic planning, pre- and post-tunnel surveys to identify the impact on settlements along the tunnel route, public consultations and coordination with other schemes to identify and mitigate the impact on the public, businesses and traffic movements.

The geotechnical design ensured the construction of the shafts and subterranean tunnels did not create excessive vibration that could potentially disrupt and damage urban settlements.

Deep gravity micro-tunnelling was used to construct the pipeline to safeguard buildings and underground services.