Green Square Trunk Stormwater Alliance
Client: DG ALLIANCE
Location: 140 Joynton Avenue Zetland,
Duration: 8 months
Commencement: May 2016
The Green Square Alliance is delivered by an Alliance of Sydney Water Corporation, City of Sydney,
Seymour Whyte, United Group Pty Ltd, Parsons Brinckerhoff Pty Ltd and RPS Pty Ltd to deliver a new stormwater drain between Link Road and the Alexandra Canal.
Scope of works:
• Install 14m of single 1800mm diameter pipe (Ch. 1769 to Ch. 1783)
• Install 140m of twin 1950mm diameter (Ch. 1783 to Ch. 1930 excluding 7m for the GPT
• Install 97m of single 1950mm diameter pipe adjacent to the existing culvert (Ch. 1930 to
• Ch. 2027)
• Form, Reo, Pour Chamber 21 (and local drainage off-take line and precast pit elements,
• grate to be cast in-situ to FSL).
• Install precast Pit 22 and associated pipe works, grate to be cast-in situ to FSL.
• Install precast Pit 24 A&B and associated pipe works, grate to be cast-in situ to FSL.
• Install precast Pit 26 and shaft, and associated pipe works, grate to be cast-in situ to FSL.
• Install a single 50m line of 1800 diameter pipe in an arc from Ch. 1890 to Ch. 1930 to
• allow construction of the GPT’s
• Installation of precast GPT inside caissons (Caisson and Pre–cast supply by others)
• FRP GPT transition structure(s)
• Install remaining 1950mm pipe(s) around the GPTs and transition structures
• Demolish existing drainage pipe between Ch. 1892 and 1930
• Management of Spear Point dewatering system
• EX6 & Northern inlet pits can be completed at the Subcontractors discretion
• Cut over south diversion to south culvert
• Lay pipe from EX3 to EX5
• Construct EX5 FRP works
• Lay pipework from EX5 to EX6 (includes miscellaneous drainage)
• Cut over north diversion to north culvert + southern inlet pits + north culvert works
• Construction of 2 Caisson Shafts up to 12 m in depth, constructed from reinforced concrete steel.