Haya Water, the agency responsible for wastewater in Oman, is completing technical evaluation of bids for a package including the extension of al-Ansab Sewage Treatment Plant (STP) and construction of Azaiba Central Pump Station.

Once technical evaluations have been approved by a committee, the commercial part of the two-envelope tendering system will be opened, with a contract award expected in early 2015.

The work involves increasing the capacity of al-Ansab STP from the existing 55,000 cubic metres a day (cm/d) to an average daily flow capacity of 96,000 cm/d and a maximum flow capacity 125,000 cm/d, and upgrading associated infrastructure. It also includes increasing the capacity of Azaiba Central Pumping Station, at a separate site, from its current 1,500 litres a second to 3,000 litres a second.

The companies that submitted bids are:

The contract for design and consultancy services was awarded to US firm Aecom in 2013.

The original al-Ansab STP was designed by Aecom. Galfar Engineering won the construction contract, completing it in 2012.

Haya Water has the mandate to build, own and operate the Muscat wastewater project under a 30-year concession, which started on 1 January 2006. In June 2014, it was made responsible for wastewater across the sultanate.

It is investing heavily in Muscat’s wastewater networks and treatment, as fewer than 20 per cent of Greater Muscat residents were linked to the sewage system in 2013.