Project: Hamana Street, Narrowneck Beach

Date: May 2015

Client:  Private residential client

Earth Stability were approached by the client to provide a full design and build solution for cliff strengthening works and a new full width glass balustrade to their cliff top property including; initial consultation, site investigation, detailed design, obtaining the necessary consents, completing all works onsite and obtaining a code of compliance on completion of the works.

The project required:

• the construction of a 20m long reinforced concrete capping beam with drilled and grouted micro piles;
• tie-back anchors to support a new glass balustrade along the edge of cliff;
• installation of 70 soilnails;
• in excess of 450 lineal metres of drilling;
• the installation of 250m2 of rock fall mesh; and
• extensive replanting of the slope on completion.

The site was located within the coastal foreshore yard and was zoned a site of ‘geological significance’ under the newly proposed Auckland unitary plan.  Access to the site was through a long and narrow pedestrian only pathway to the side of the property requiring all plant and materials to be mobilised by hand.  It required us to work at a height of 15 metres over Narrowneck Beach, a public beach which is heavily used all year round. 

As a consequence of these factors, a specific methodology needed to be adopted which would prevent damage to the highly sensitive environment and which would also exceed all of the requirements for working within each of the zones.

In addition, all works were completed over the peak of summe.  Consequently a requirement of the Project was that it was completed with no delays and with no disruption or impact to the large volumes of public visiting Narrowneck Beach.  Earth Stability methodologies are innovative in their engineering approach and perpetually place importance on health and safety and environmental issues.  As such, this requirement was successfully met.

Work was completed on time, to budget and exceeded client’s expectations. 

The quality of the completed project and cooperative working relationship with the client lead to two additional projects on neighbouring sites through direct negotiation.