DEFENDER LANE MASS MOVEMENT REMEDIATION

The 2010 Canterbury and 2011 Christchurch Earthquake has cause many hill slopes to become unstable and a danger to public. CCC contracted GNS Science to assess and identify high risk areas that requires immediate rectification attention. The road Defender Lane is located in the Redcliffs suburb, approximately 10kM away from Christchurch City. It sits on top of a slope and there are a few houses located at the foothill. After the 2011 earthquake, significant localized cracking was formed on the slope. The amount of slope displacement coupled with steep slope angles, suggested that there is risk of debris flow impacting the foothill houses. CCC has appointed Stronger Christchurch Infrastructure Rebuild Team (SCRIT) to undertake the remediation works. URS was tasked to undertake the design of a debris flow protection structure at the foothill. The debris volume was estimated to be 700 – 1,000 cubic meters and debris impact velocity was assumed to be 5.0m/s.