Table 2 – Assumptions of construction and liner details for waterway

Waterway section Construction method Permanent & support lining class
Headpond Concrete
Headpond dropshaft Concrete
Headpond dropshaft Drill and blast Unlined rock
Main headrace tunnel TBM Unlined rock
Main headrace tunnel TBM Shotcrete
Downstream dropshaft Drill and blast Concrete
High pressure headrace tunnel Drill and blast Concrete
High pressure headrace tunnel Drill and blast Steel
Penstock & PS Steel
Tailrace Cut and cover Concrete