STEP (STRATEGIC TUNNEL ENHANCEMENT PROGRAMME)

The concept of the proposed Strategic Tunnel Enhancement Programme (STEP) system was to use a series of link sewers to intercept flows from existing gravity sewers upstream. The idea was to transfer the flows by gravity into the deep tunnel sewer, thereby providing relief to the existing main collector system. These flows will again be transferred by gravity via the deep tunnel sewer to centralized wastewater treatment facilities strategically located at Al Wathba, at the southern end of the metropolitan area of Abu Dhabi.