The site’s challenge involved high tide site flooding requiring the team to develop a solution to block the large stormwater outlet culvert from the ocean influence while work was performed.

Peter Sherwood proposed installing a plug and high-density foam in the culvert, which was approved by Melbourne Water and John Holland-KBR Joint Venture. Installation went off without a hitch, and the clients were impressed with the finished product.

Handling the high-density foam was a careful process due to its sheer size and fragility. Realising how thin the high-density foam was, we constructed trusses on-site to fit between the foam and the culvert roof and used form ply as compensation plates to distribute the load over the foam as the plug inflated. The foam was lubricated with cable lube to help the plug slide over the foam without damaging it. The chain held the plug in place once inflated. The plug was inflated to 5 PSI and held well. Plugs diameter finished at 2M – trusses worked a treat with no movement or foam damage once the plug reached pressure.