This guideline provides a framework for assessing technical resilience of three waters piped assets.
It has been prepared to support local authorities and the private sector (including asset managers, operators and engineers) at local and regional levels with assessing technical resilience and in developing strategies to improve network resilience, and inform pre-event planning and post-event emergency support and recovery.
The Christchurch Earthquake Sequence of 2010-2011 caused extreme and widespread damage to the 3 waters pipe network of Christchurch. Most of this damage was caused by liquefaction and lateral spreading. Researchers and practitioners have learnt many lessons in assessing liquefaction damage from these experiences. This report develops tools to assess the potential for pipeline damage based on correlations with liquefaction-induced ground movement and CPT-based liquefaction metrics. The correlations can be used for pre-event estimates as well as post-event rapid triage of pipe damage. Key inputs to the assessment are pre and post-event LiDAR surveys; satellite imagery; CPT-based assessments of liquefaction vulnerability and Peak Ground Velocity (PGV).
The document provides guidance for asset managers on the renewals process and discusses how to communicate issues related renewals planning to decision makers such as senior management or councilors, finance staff and auditors. The questions that decision makers should expect asset manager to address when proposing renewal plans are summarized.
While this document is focused on the renewal of gravity wastewater pipelines, the concepts and recommendations provided in this document are generally applicable to potable water and storm water networks.
The New Zealand Pipe Inspection Manual (NZPIM) is a document that is extensively used by the water industry to assess the condition of waste and storm water pipes. It was last updated in 2006. Since that time, there have been a large number of technical advances. In addition, the NZ$100 million spent on inspecting the Christchurch 3 waters network after the Canterbury Earthquake Sequence provided a number of lessons that need to be captured in an update. As part of the Evidenced-based Decision Making for 3 Waters Networks project, the Quake Centre with the asistance of EQC engaged ProjectMax to undertake a full review and scope of the required changes to the NZPIM. This exercise has now been completed and the report is out for comment across the water sector.
The Pipe Renewals Programme is a collaboration between the Quake Centre, Water NZ and IPWEA to develop an integrated suite of guidance material. This guidance aims to foster national alignment of best practice investment decision making across the whole of New Zealand. It is expected that this project will take about 10 years to finish. The document below sets out the road-map for this programme.
This document is the output of the workshop in which the framework for this guidance material will be created.
Learning from the Christchurch Earthquake sequence and other disasters has highlighted the need for New Zealand’s 3 Waters Services to be seismically resilient. In the context of these guidelines the key aspects of a resilient system are: