Gabion Baskets: An Effective Means of Erosion Protection

Takarau Gorge Road and Makara Road, located to the west of Wellington New Zealand are subject to regular erosion damage from adjoining streams.

The geotechnical hazards present along these roads include slips both above and below the road, degradation of the streambed, erosion of the stream banks and loss of fine materials from beneath the carriageway. A variety of retaining and erosion protection structures have previously been built to protect the carriageway. Following a 100-year return period storm event in February 2004 failures of slopes and retaining structures occurred.

Gabion basket walls have become a preferred option for carriageway protection as they are flexible and, if adequately designed and detailed, have the capacity to withstand differential settlements and scour.