Around 85 per cent of the two sea outfall projects in Darsait and Al Athaiba have been achieved and the project is expected to be completed by end of current year, Oman?s Haya Water has announced
According to Times of Oman, the company said that the two sea outfall projects will help to discharge mixed raw sewage and storm water during storm and cyclones.
The Darsait sewage treatment building coincides with the establishment of the two outfall projects in Darsait and Al Athaiba. This project is considered to be of significance because it discharges surplus of treated effluent (TE).
The main objective of both projects is to ensure that the discharges cause no environmental degradation of the coastal region and that the outfalls will provide a future-proof solution, avoiding adverse impact on beaches and at a nearby desalination plant. Last year, the company successfully completed the construction Al Seeb outfall.
Technicas Reunidas and Sarooj Construction Company joint venture was appointed by Haya Water to execute detailed design and construction works in August 2014.
In 2010, Haya Water appointed Halcrow to carry out feasibility studies and develop designs for emergency marine outfall at two prime locations, from Darsait Sewage Treatment Plant (STP), the third largest STP in Muscat, and from Al Athaiba Central Pumping Station (CPS), which pumps all the collected sewage from Bausher catchment into Al Ansab STP, the second largest STP in Muscat.
Networks are dedicated for transporting sewage storm and rainwater to enter them via sewage manholes designed to handle limited amount of storm flow.
A comprehensive series of surveys and investigations have been conducted together with detailed design work including 2D and 3D hydrodynamic dispersion modelling, environmental impact assessment (EIA), hydraulic, surge and structural analysis.
The proposed outfalls are 1,600mm dia high density polyethylene (HDPE), extending up to 3,100 metres long in water depths up to 22 metres in Al Athaiba and 2,500 metres long in water depth up to 45 metres in Darsait.