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

ial 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 12

4,000 m³ measured in solid rock (in situ).