Sultartangi Power Station – Enlargement of the headrace tunnel cross-section

It is proposed to carry out an enlargement of the headrace tunnel cross-section at the Sultartangi Power
Station. The project area is located at an elevation of approximately 260–280 m a.s.l., within a designated industrial area.
The headrace tunnel is approximately 3.4 km in length. The existing tunnel has an elliptical cross­section with an approximate area of 152 m². The proposed enlargement involves lowering the tunnel invert by 4.5 m below the existing level. The estimated excavation volume is approximately 124,000 m³ measured in solid rock (in situ).