Scope

• Establishing site safety measures, including installing a static line on the dam wall for fall arrest.
• Deploying sediment logs to filter wash waters before discharge into the river system.
• Utilising a recycling combination unit to conserve water.
• Verifying drainage parameters, including diameter and depth, before and after cleaning.
• Vacuum loading drains post-cleaning.
• Surveying drainage holes.

Challenges

• The project was conducted in December 2023, amidst hot weather conditions with temperatures averaging around 36 degrees Celsius daily. The radiant heat from the dam wall further elevated temperatures by 10–15 degrees. To ensure the well-being of the work crew, hydration breaks were prioritised, and operator fatigue was closely monitored.
• Limited telecommunication due to the remote location necessitated the use of two-way radios for clear communication among operators, data recorders, and other onsite contractors.

The outcome

The client now possesses accurate depth data for drainage holes, some of which were established in 1965 without any prior recordings. Additionally, an average of 1 meter was gained in depth due to the cleaning and removal of sediment from each drainage hole. With all drains cleared, the pressure on the dam wall has been significantly reduced.