As the NZ Transport Agency continues its Dunedin to Port Chalmers safety improvements the agency says it is satisfied its work will not create permanent changes to the environment.
The agency says the birdlife displaced now will recolonise disturbed areas once construction is done.
However, after another reclamation project in the West harbour, at Burkes Bay, University of Otago geography associate professor Mike Hilton said councils had to be "very, very careful" when allowing a change to the natural character of the area through what seemed to be piecemeal projects.
Prof Hilton, a St Leonards resident, said engineers were good at designing structures but they had to integrate their structures into the existing landscape otherwise they would create a "formal landscape".
While he did not question whether the Burkes Bay work was justified, he said the work should not be treated in isolation, but instead should be seen as part of a larger ongoing process of reclamation in the West harbour out to Port Chalmers.
The Otago Regional Council granted consent to the transport agency to reclaim the edge of the harbour at "the corner of Finch St and State Highway 88" to construct a seawall and widen the highway.
Regional council staff noted that there had been a large amount of reclamation undertaken in the harbour, but in its recommendation report for the work, staff said most of the work in the harbour had been around the Portobello area.
There had been a limited amount of reclamation undertaken on the Port Chalmers side of the harbour, and so the cumulative effect of reclamation would be kept to a minimum, the staff report said.
Aukaha on behalf of Te Runanga o Otakou, Heritage New Zealand, and the Department of Conservation were considered affected parties.
Council consents manager Joanna Gilroy said consent conditions for the seawall construction required the transport agency to provide the relocation or placement of rocky foreshore habitat, where appropriate, to account for habitat loss from the reclamation, she said.
NZ Transport Agency senior project manager Jason Forbes said the the ecological assessment the agency commissioned for the Burkes Bay work was done by the same consultant as a first assessment of the Dunedin to Port Chalmers safety improvements project as a whole.
That assessment said the impact on the intertidal area were likely to be transitory.
Most species would "readily" re-colonise disturbed areas after construction, Mr Forbes said; and before and after surveys of similar work carried out along the Harington Point Rd showed this occurred within one to two years.
"The harbour is a feeding ground rather than a breeding ground for most birds and therefore this should not change," he said.
"While I was recently on site in the Burkes area, shags were roosting on the new reclamation despite machinery working directly adjacent and the works appear to have had minimal impact on the birdlife."
He was aware of some residents’ concerns over losing a bird roost, but birds had returned after the reclamation work was done.
The agency was reclaiming into the lagoon to provide the width to extend an existing path from the existing access, back to the Finch St intersection, he said.
The highway’s city-bound lane would also be moved towards the lagoon, providing space for both a right turn bay into Finch St and a pedestrian crossing island, so that path users would only need to cross one lane at a time.
Safety barriers would also be installed throughout the section of road where the work was being done to prevent vehicles from running off the highway and careening into the harbour, he said.
