Dunedin dune work to protect coast
Dune work to protect coast
(Dunedin, Tuesday, 20 March 2018) – A series of notches will be cut along the sand dunes below John Wilson Drive this week to encourage natural growth of the dunes and reduce the impact of erosion.
Dunedin City Council Group Manager 3 Waters Tom Dyer says, “The notches are a simple way of building up the back of the dunes by making it easier for the wind to shift the sand to where we want it to go.”
The notches are designed so that the wind will blow sand to the back of the dunes in strong west to south-west winds, allowing the dunes to grow over time and become more resilient to erosion caused by storms and rising seas. Vegetation will grow on the new sand over time.
People will be able to walk through some of the notches to get to the beach more easily. Less accessible notches may provide spaces for New Zealand sea lions to rest.
“This work will protect the area while we develop longer term strategies for managing coastal erosion in Dunedin,” says Mr Dyer.
The project follows a small scale research trial in 2016 that successfully built up dunes, and the DCC is developing a monitoring programme with the University of Otago.
Associate Professor Mike Hilton from the Department of Geography says, “The DCC is showing a great deal of innovation and foresight in this project. This is the first time, internationally, a local authority has managed a foredune in this way, in order to protect coastal assets from storms while working to improve public access to the coast.”
“This is an exciting development for the coastal scientific community and the people of South Dunedin, and the results of the work will be closely followed.”
Dozens of notches will be cut at 10-15 metre intervals between the St Kilda Surf Lifesaving Club and Lawyers Head. The notches will be 1.5-2 metres wide and 1-2 metres deep. Spotters will be on the beach and at access points to let people know where the excavator is working.
The work is expected to take about a week
starting on Wednesday, 21 March (weather permitting) and to
cost around $4000.