Cleveland Dam Airshaft Service Elevator and Ducting System

The primary challenge was to improve access to the underground galleries of Cleveland Dam by installing a new service elevator within an existing 60-metre-deep airshaft. The elevator needed to safely transport personnel, equipment, and, when required, an injured worker on a stretcher. 

The airshaft’s original purpose was to provide airflow to two Howell-Bunger valves located at its base. As a result, the shaft was exposed to high humidity, water infiltration, and environmental conditions conducive to ice formation. These conditions created significant risks of corrosion and premature deterioration of the new elevator. 

 A secondary challenge was to ensure that the infrastructure remained adaptable to future projects, including the planned installation of power generation equipment at the site. 

Norda Stelo implemented an integrated approach to address access, ventilation, and equipment protection requirements simultaneously. 

The team first conducted a detailed assessment of airflow patterns, water infiltration, and ice accumulation within the shaft. Based on these findings, a dedicated ducting system was designed and installed to provide airflow directly to the Howell-Bunger valves while isolating the elevator from the wet environment. 

To further protect the infrastructure, several strategically located gutter rings were installed to collect water seeping through rock fissures and reduce exposure to mist and moisture. 

With a long-term perspective, the airshaft building was designed with a removable roof hatch to facilitate maintenance activities and support the future integration of power generation equipment. 

The project included the installation of a new service elevator within Cleveland Dam’s existing airshaft to facilitate access for personnel, equipment, and rescue operations to the underground galleries. 

The design and installation of a dedicated ducting system provided a direct airflow path to the Howell-Bunger valves while reducing the elevator’s exposure to moisture, mist, and conditions conducive to icing. 

Strategically located gutter rings were installed to collect water seeping through rock fissures. The airshaft building was also designed with a removable roof hatch to facilitate access to the installations for future projects, including the potential addition of power generation equipment. 

• Installation of a new service elevator within an existing 60-metre-deep airshaft. 

• Safe transport of personnel, equipment, and an injured worker on a stretcher. 

• Detailed verification of airflow conditions and water and ice accumulation within the shaft. 

• Design and installation of a dedicated ducting system to mitigate corrosion and icing risks. 

• Integration of strategically located gutter systems to manage water infiltration. 

• Design of a building with a removable roof hatch to facilitate future projects. 

• Provision for future installation of power generation equipment. 

• Electrical
• Mechanical
• Structural