Infrastructure Strategy 2.3 Ageing infrastructure Option Implications Option Implications Provide financial Benefits Renew non-critical Benefits contingency to Recognises damage from any particular earthquake is difficult mains when failure replace these pipes to predict and saves money to use in response to damage rates become Ensures that only pipes that have reached the end of their urgently if a following actual events. intolerable. useful life are replaced. significant earthquake occurs. Costs Costs Downstream customers will experience a deterioration in Disrupted water supplies and longer restoration times will service as supply interruptions increase. Operation and increase public health risks and reduce levels of service maintenance costs will increase. following an earthquake. Materials and resources will be in short supply, which means premium costs would apply to Unpredictable renewals make budget and resource planning undertake restoration works. Emergency repairs followed by difficult. Unplanned work is more disruptive and expensive than renewals will duplicate costs in some instances. a planned programme of renewals. PREFERRED Benefits 3. Most likely scenario OPTION Avoids unacceptable deterioration of the level of service and 3.1 Drinking water standards Implement a allows efficient, targeted investment in planned renewals The most likely scenario is that the Council will complete the upgrade of water proactive, planned works. treatment plants to meet the requirements of the DWSNZ for all water supply areas. pipe renewals Costs The design and build of a treatment plant to serve the Seddon township is well programme and advanced at an estimated $4.45 million. Renwick and Havelock treatment plants are invest more in Additional costs of pipe sampling, analysis and data collection planned for completion in 2020 and 2021 at a cost of $6.0 million and $4.9 million condition to improve pipe and asset condition assessments and ensure respectively. assessment well targeted renewals and efficient investment. technology, field As an alternative to building a large treatment plant for the Awatere Rural supply to data collection and disinfect the water before it is distributed, it is more practical to install small treatment data management. units to each dwelling at the point of entry of the supply pipe. 2.4 Earthquake risk This approach will consist of around 540 small disinfection units. The installation cost Option Implications of this has been estimated to be around $1.5 million. However each unit will need to be regularly serviced and the costs of ongoing maintenance will increase. PREFERRED Benefits OPTION Will increase resilience to pipeline damage and assist with Cost estimates have not been completed for treatment to Wairau Valley but are likely Prioritise more rapid recovery following a large earthquake. to be less than $559k. replacement of Costs asbestos cement It is likely that all supplies will need to be chlorinated as a result of the Government and cast iron pipes The total value of the asbestos cement and cast iron water Inquiry into the Havelock North drinking-water contamination incident. If this change in areas where they mains is around $50 million. To replace all pipes of these occurs, some additional plant would be required at the Blenheim treatment plants and have deteriorated materials in the next 30 years it will be necessary to bring there would be ongoing operational costs. more quickly than forward the replacement of 94kms of pipe at an approximate anticipated. cost of $28 million. A recommendation of the enquiry is to remove the status of ‘secure bore supply’ from the drinking water standards. If this recommendation is adopted treatment of the 2018-2028 Long Term Plan Page 191