As part of the government ‘Opening the Reservoirs’ program, the Happy Valley Water Treatment Plant was upgraded with a new UV disinfection plant. BluBuilt was engaged to undertake the detailed civil works relating to construction of the new UV bunker, outlet and inlet tanks, and peripheral services and pavements.

The works included:

• Diversion of existing services across the proposed footprint
• Bulk excavation (>6m deep)
• Subgrade preparation
• Structural concrete works for the new UV Bunker, and water retaining outlet and inlet tanks
• Installation of pipework cast-ins, and backfill
• Modifications to the existing structural concrete inlet feed box / weir
• Construction of all external pavements (roadways and paths).

As there were steep batters requiring detailed geotechnical investigation and approvals, we implemented a batter stability assessment process to manage the associated risks. The site also had a limited access footprint, so staging was paramount to the project’s success. We had to work to a tight, government mandated timeframe, structured around opening the reservoir. We developed an innovative wall pour strategy that allowed us to maintain the schedule.