Client: Coliban Water

Location: Huntly/Epsom

Contract Type: Construction

Value: 5.8 Million

As the principle contractor for Coliban Water, Girdwood Contracting PTY LTD completed the Huntly / Epsom sewer upgrade over the course of six months, on time and within budget. The project included the construction of two 8.5m deep pump stations, a 200,000L storage tank, 11.5km of rising main and 110m of gravity sewer. As a result of the new infrastructure Girdwood Contracting were able to decommission four existing pump stations.

The Sawmill Rd, Huntly Pump station and storage tank;

• 8.5m deep pump station excavated using box shields
• Two Flygt submersible pumps with a total capacity of 40L/s
• 20mx6m benched 7m deep excavation to install the storage tank

The Epsom Recreational Reserve pump station and gravity sewer;

• 8.5m deep pump station installed through the use of sheet piling
• Two Flygt submersible pumps with a total capacity of 70L/s
• 44m laser guided gravity sewer bore beneath the Midland Hwy at a depth of 6.5m
• 58m of trenched gravity sewer at a depth of 6m
• The construction of four maintenance holes ranging from 6.5m to 4.5m deep

5.5km of single rising main and 3km of dual rising main all in PN16 280mm polyethylene rising main

• Directional drilling
• Bucket wheel trenchers
• A fleet of excavators and smaller machinery
• Varied conditions including sand, clay and rock
• Engagement with local residents and contractors

Pump station decommissioning

• Allen St pump station, 2m removed and the remainder backfilled.
• Ironstone Rd pump station, converted into a maintenance hole
• Sullivan St pump station, converted into two adjacent maintenance holes
• Sawmill Rd Interim pump station, converted into a maintenance hole