Tunnels in the left abutment of Marun dam…
Tunnel Diameter Cross-section Length Lining
Diversion tunnel #1(DT1) 11m Horse shoe 494m 60cm
Access tunnel to the crest 6.5m Horse shoe 404m Unlined
Access tunnel to the gate chamber 7.5m Horse shoe 538m Unlined
Bottom outlet 6m Circular 494m Steel & concrete
        60-80cm
Pressure tunnel 3.5m Circular 396m Steel and concrete
        60-80cm
Diversion tunnel #2 (DT2) 13m Circular 683m Unlined