South Coast Erosion Set for Repair

20 May 2014

Work to protect part of the South Coast from erosion caused by sea swells is starting soon at Princess Bay, and options are being explored to repair the Island Bay sea wall damaged by last year's June storm.

Sand dunes alongside the Esplanade at Princess Bay.

The Esplanade, Princess Bay

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Princess Bay

Work is due to start next month on a concrete retaining wall to protect The Esplanade at Princess Bay from erosion caused by big seas in southerly storms.

Regular users of The Esplanade will be aware that parts of the footpath on the seaward side of the road have collapsed or been undermined.

One section of footpath collapsed in February 2013 and more of the pathway was damaged in the severe southerly storm that hit Wellington last June. A total of about 80 metres of footpath has been affected.

Council staff, in conjunction with geotechnical consultants Tonkin and Taylor, agree that urgent remedial engineering work is needed on the cliff below the road to prevent further erosion that will ultimately destroy the road.

The Council’s City Networks Manager, Stavros Michael, says expected rises in sea level and the severity of storms due to climate change mean it is considered necessary to build a wall that will last at least 100 years while also not taking up too much space on the beach at Princess Bay.

“We’ve looked at various options and our preferred solution is to construct a high concrete retaining wall with a smaller rock support at its base.

“This design will encroach only one or two metres on the beach. It will also be strong enough to add a widened suspended path for pedestrians and cyclists in the future.”

In order to build the wall, and provide beach access for machinery, some of the sand dunes and vegetation will have to be excavated. This area will be replanted and landscaped. Construction is expected to begin in June and be completed by mid-October. Public access to the beach will be restricted during this period.

Island Bay

Options for the Island Bay sea wall damaged in last year’s June storm are being explored with the community as to how this area could more readily cope with storm surges and expected rises in sea level.

These include:

  • restoring the seawall as it was
  • shifting it further inland into the park and increasing the beach berm
  • removing the seawall, expanding the beach to link with Shorland Park and encouraging the return of natural sand dunes and vegetation.

To test this option, a trial road closure is proposed for The Esplanade between Reef and Derwent streets. To find out more:, see:
Projects - Island Bay Seawall Replacement