Rehabilitation of the Burrungubugge Intake Shaft to Help Maintain One of the Civil Engineering Wonders of the Modern World

The Burrungubugge Intake Shaft is a critical structure in the Snowy Mountains Scheme. The Burrungubugge Intake Shaft was constructed by drill and blast through granite in order to siphon water from the Gungarlin and Burrungubugge Rivers into the Eucumbene-Snowy Tunnel, a 23.5-mile water diversion tunnel for the scheme. The 6-foot diameter, 433-foot deep, vertical shaft had deteriorated over the years in the form of stress cracking, corrosion, and tears in the steel liner. Continued deterioration of the steel liner introduces a danger of collapse and a loss of the intake shaft. The distress to the liner was caused by complex hydraulic forces and was not fully understood until engineers completed a detailed analysis including hydrodynamic finite element modeling. Based on the analysis, a repair methodology was developed that required a coordinated effort between various specialty contractors and the owner. This paper will review the project in detail, including the analysis, the repair methodology, the field quality control, and advanced construction procedures required to implement the repairs.