Sydney Water Desalination Project

Scope of Works

• Mobilisation to site of the Nu Bounty and Nu Endeavour, 2000 hp booster station, 2 x purpose built spreader barges,3600m of 18” pipeline and multiple support vessels,
• The dredging of a berth pocket &navigation channel on the Kyeemagh foreshore to provide marine access to the shore based staging area. This involved dredging of approx. 70,000 m3 and pumping the material 2.7 kms to a temporary underwater storage area,
• Dredging of the pipeline trench and concurrently backfilling of the trench post pipe lay across Botany Bay to a +/-200mm vertical tolerance. The pipe laying program required 120 lineal metres of trench to be dredged and backfilled per day. The volume of material involved to meet the program required both the Nu Bounty and Nu Endeavour to be engaged on site. The trenching and pipe laying was undertaken with both Nu Endeavour and Nu Bounty, the pipe lay barge and both spreader barges working“ in train” together working across Botany Bay. The pipeline trench was 6,970metres long, starting from Kyeemagh on the northern side of Botany Bay finishing at Kurnell on the south west side of Botany Bay. The design of the pipeline trench required 710,000 m3 of material to be dredged and back filled during this phase of the project.  This part of the project required significant interfacing between the various marine operations and was undertaken on a 24/7basis,
• Backfilling of the final 1,500 lineal metres of trench, post pipe lay, dredging 220,000 m3 of material from a temporary underwater storage location,
• Detailed dredging for removal of tunnel boring machines,
• Dredging of 70,000 m3 for the backfilling and restoration of Kyeemagh berth pocket.