Commercial Fishing Base No.2 (CFB2) is located on Chinaman Creek near the Maritime Safety Queensland base. Road access is via CFB2 Access Road off Tingira Street, Portsmith, Cairns, QLD.
The wharf forming CFB2 was constructed in the late 1980’s and primarily consists of a steel substructure with a pre cast concrete deck. The original water main was constructed from 100mm galvanised steel and protected with denso
wrapping. The reticulation forms a ring main, approximately 300lm, around the outer edge of the concrete deck. Painted steel brackets attached by bolts through the deck are utilised to fix the pipe work to the wharf. The position of this water main renders it vulnerable to impact damage from fishing vessels and over time there have been many sections of pipe and brackets physically deformed.
Significant water main failures commenced from 2012 when the asset was around 25 years old. Over a 4 year period approximately 100m of the galvanised pipe was replaced but not protected with denso wrap and some sections are already showing signs of significant surface corrosion. Of the remaining 200m approximately 50m is damaged. The remainder is difficult to assess by visual inspection only but the denso wrapping is damaged so not providing a reliable corrosion barrier and there are spots with isolated leaks. Given the age of the original galvanised main is reaching 35 years, within a corrosive marine environment, the risk of continual leaks caused by pitting in the near future is high.
Since 2012 this water asset has cost the Port $40K to maintain. Therefore, more sustainable water supply options will be considered for the future of CFB2. A fire system is not required on CFB2 so nonmetallic options such as polyethylene can be utilised. Ports North are open to consider any sustainable options with whole of life cost benefits.
The benefits of installing a polyethylene water main suspended centrally under the deck next to the electrical cable ladder include;
Halving the linear distance of the main line
Eliminating the risk of vessel impact damage
Clearing services away from the steel girders which will significantly reduce future blast and paint maintenance costs
Eliminate corrosive metallic materials
Increase asset life and reduced whole of life costs
Simple to repair in the event of damage
Lower cost than maintaining and upgrading the existing reticulation with denso wrapped galvanised steel
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