Client: South Port NZ

In 2020 South Port NZ Ltd commissioned e3Scientific to prepare an assessment of marine ecological effects to support their notified capital dredging campaign Kia Whakaū. The dredging campaign was to deepen the entrance channel and berths in Bluff Harbour and involved the removal of up to 120,000 m³ of soft sediment via trailing suction hopper dredge and 40,000 m³ of rock via a drill and blast methodology. It also required the establishment of a new spoil disposal site within Foveaux Strait for the deposition of the rock material.

As part of the assessment of marine effects, e3Scientific undertook scientific diving surveys to assess benthic ecology, sediment composition and chemistry, sediment mapping, and deployed marine mammal acoustic data loggers at 3 sites within the harbour for 12 months. e3s also supported avifaunal assessments, completed subtidal mapping of seagrass and kelp beds and investigated appropriate disposal sites via video sled and dive surveys within Foveaux Strait.

A report, adaptive marine management and monitoring plan and tiered turbidity limits consent conditions were prepared as part of the notified application, resulting in a successful consent application and dredge campaign which was completed in September 2023. e3Scientific have since completed several of the monitoring programmes for this project which include rocky reef surveys, turbidity assessments, seagrass surveys, and biosecurity surveys.