Wakrah and Wukhair Drainage Tunnel is the development of 13.3 km long drainage tunnel with 8 permanent access shafts (at WS10, AS11, WS09, AS10, AS09, WS08, AS08 and WS07) and is aligned within the Western and Southern utility corridor an assigned buffer zone between the two utility corridors and inside the Al Wakrah & Al Wukair Sewage Treatment Plant (STP) site. The temporary work shaft (WS10, WS09, WS08 and WS07) of TBM shall be converted into permanent access shafts, whereas additional shafts shall be constructed (AS11, AS10, AS09 and AS08) between above TBM shafts. EHAF is acting as Lead Design Consultant for the project.