By rosebell
With 9.25m hight, 6m width and just under 500m length, breakthrough has been achieved on the bottom outlet tunnel for Lesotho’s Polihali Dam.
The date of commencing digging of the top heading of the tunnel, wich is the upper portion of the tunnel in cross-section, by drill and blast method was earlier this year its daily advance was almost 2.4m.
The next five weeks is scheduled date for starting excavation of the bottom heading of the tunnel.
In order to generating hydroelectricity, the bottom outlet tunnel is due to carry compensation water permanently to downstream users.
Adding 2.325 million m3 in storage capacity to the Lesotho Highlands Water Project, the Polihali Dam is finally going to create a 5,053ha reservoir on the Senqu and Khubelu rivers at full supply level.
Tags: # Polihali Dam Project # Outlet Tunnel # Breakthrough # Lesotho # Tunneling
