Australasian Coasts & Ports Conference, 2023, Sunshine Coast, Queensland
The Ōpōtiki Harbour Development (“OHD”) is the first river port to be constructed in over 100 years in New Zealand. Te Whakatōhea have developed an offshore mussel farm and onshore processing factory and need a navigable harbour entrance to connect these resources. Show more…The OHD scheme comprises twin 400 m long training walls to fix a dynamic river mouth, around 700,000 m3 of dredging in intertidal and subtidal areas and approximately 20 hectares of constructed fore and mid dune to close the existing river mouth. The OHD is located in a sensitive estuary environment fed by two major rivers. The estuary contains numerous threatened fauna, is subject to constant morphological change and provides an important recreational resource for the Community.
To ensure opportunities for innovation in design and construction were optimised, the resource consents granted for the OHD deferred most environmental impact avoidance, remediation, or mitigation to a suite of Environmental Management Plans (“EMP”) to be prepared in parallel with the Detailed Design of the project. These EMP manage a range of impacts, such as sediment contamination, saline wedge connection to inanga spawning habitat, disturbance to dotterel breeding areas, water quality (TSS and clarity), native fish migration, training wall related downdrift erosion, and sediment deposition within riverine riparian vegetation and seagrass assemblages.
Timeframes to design and construct the OHD were very tight with many inter-dependencies in the project plan. The Technical Liaison Group (“TLG”) comprising representatives of tangata whenua and a range of regulatory agencies were required to contribute to the development of the EMP.
To ensure the OHD project was delivered within a compressed programme, meticulous planning and execution of the environmental management regime was required. To this end, partnership was key. The OHD design and construction project team worked with the ocean, rivers, nature, tangata whenua, regulators, the Community, and other professionals.Show less…
