Muharraq Sewage Treatment Plant (STP), Bahrain
The Bahrain Ministry of Works' (MOW) Muharraq Sewage Treatment Plant (STP) project, located on reclaimed land in Bahrain, is scheduled for completion in 2014. The plant will have a treatment capacity of 100,000m³ per day. The project is being overseen by the Muharraq STP Company as part of a 27-year build, own, operate and transfer (BOOT) scheme, the first scheme of its kind in the country.
The sewage treatment agreement (STA) for the privatisation of the project was awarded in February 2011. The groundbreaking ceremony for the project was held in July 2012.
The plant is designed to have a lifespan of 25 years and has a provision for future expansion to treat 160,000m² per day. The project site covers an area of about 157,000m². The project won the Middle East Water / PPP Deal of the Year 2011 awarded by Project Finance Magazine.
Muharraq STP project details
The project primarily involves construction of the sewage treatment plant (STP), a deep gravity sewer (DGS) and network connections. The STP and DGS are expected to be completed by 2013, while the network connections will be completed by 2014. The DGS is expected to have 80 years of service life.
The network connections will intercept 24 existing pump stations and divert the flows to the deep gravity sewer pipeline. The deep gravity sewer will further discharge the flows to the terminal lifting station to be constructed at the head of the new sewage treatment plant.
The deep gravity sewer will measure 16km in length and 1.8m in diameter. The sewer is being tunnelled using the micro-tunnelling method.
The project also involves the construction of a lift station halfway through the route to lift the flow, further preventing the depth of the sewer from exceeding 15m below ground level.
A new sludge incinerator plant to treat the sludge from the sewage treatment plant will also be installed. Treated sludge from the plant will be used as fertilisers in agricultural fields. The STP also has an option to discharge the treated effluent and bypass flows to the sea through a sea outfall. As of March 2013, the project achieved one million safe man-hours without lost-time incidents.
Sewage treatment plant technology
The treatment plant will implement established technology, including pre-treatment, nutrient removal, filtration equipment implementing disc filter technology capable of capturing particles as small as ten microns and disinfection using both UV and chlorine.
Contractors for the Muharraq STP's design and construction
The Muharraq STP Company comprises of Samsung Engineering, Invest AD and United Utilities which hold shares of 45%, 35% and 20% respectively. The joint venture between Samsung Engineering and United Utilities will operate and maintain the facilities.
Hyder Consulting is providing the detailed design services for the STP. The main construction contractor for the project is G.P. Zachariades.
The installation of the piles for the shafts is being carried out by Keller. The piles used for the shafts range in sizes from 12m to 18.5m. Implenia has been sub-contracted to carry out the micro-tunnelling activities. The nutrient removal reactor for the plant will be supplied by Siemens.
Financing Bahrain's Muharraq sewage treatment plant
The project financing for the treatment plant was completed in September 2011, with Macquarie Capital acting as the financial advisor and Ashurst acting as the legal advisor to the consortium.
HSBC and Norton Rose, on the other hand, respectively acted as the financial advisor and legal advisor to the Bahrain Ministry of Works and Ministry of Finance.
The banks involved in the financing are Export-Import Bank of Korea (K-Exim), Credit Agricole, Natixis and Sumitomo Mitsui Banking Corporation (SMBC) with Shearman & Sterling acting as the advisor for these lenders.
The debt financing for the $325m project includes a $124m direct loan guarantee from K-Exim, a $83m guarantee covered by K-Exim and a $43m uncovered guarantee, with a 13.7% standby facility on each.
In January 2008, Bahrain-based Energy Central Company (ECC) was awarded a 25-year contract to design, build and operate a seawater desalination plant to serve the irrigation needs of the entire Durrat Al Bahrain development.
The Government of Bahrain has instigated a $360 million project, involving the construction of the Al Hidd power and desalination facility on Muharraq Island.