Waldronville Outfall Extension

Waldronville (Green Island) Outfall Extension, Dunedin

OCEL was engaged to provide design services to a design and build contract carried out by McConnell Smith Limited to extend the existing outfall by 370 m in 940 mm OD PE pipe. This included a 70 m diffuser terminating on a rock reef in 17 m water depth. The original outfall comprises twin 800 OD PE pipes. Installation of the outfall extension was carried out from a temporary moving island structure designed by OCEL, and the new pipeline buried beneath lowest known seabed profile, rising up to discharge above the reef. Site is very exposed to southerly conditions, the outfall alignment due south with full southern ocean exposure.