Long Term Plan 2018-2028 Workshop Water Services Purpose: To discuss Water Supply and high-level direction of the AMP and LTP 13 June 2017
What does the community expect of Water Supply? That its there when I turn on the tap! That its safe and OK to drink?
Water Supply is primarily about public health protection and risk management. Presentation Content Contaminants, legislation & standards (DWSNZ), multi-barrier approach Public Health Our sources, treatment and distribution systems Our Water Supply General Risks Risk Management Water Safety Plans Havelock North New Projects Operational Risks Existing LTP Projects Condition assessments and renewals Financial Levels of Service, Growth, Climate Change, Fluoridation, Summary, Questions
Drinking Water Contaminants Three broad categories of Drinking Water contaminants • Microbiological • Chemical • Physical Microbiological are the most important as they have the potential to cause widespread illness in very short period of time
Bacteria doubling every 10mins time hrs bacteria 0 1 1 64 2 4,096 3 262,144 4 16,777,216 5 1,073,741,824 6 68,719,476,736 From human or animal faeces. E-coli used as an indictor of probable presence. Removed by coagulation and filtration, destroyed by Chlorine E.Coli magnified 15,000 times
Viruses • Smaller than bacteria • Use a living cell to reproduce • Hepatitis A • Killed by Chlorine
Protozoa • Cryptosporidium and Giardia • Caused many deaths around the world with contaminated drinking water • Very resistant to Chlorine • No medical treatment • Removed by coagulation and filtration, inactivated by UV
Cyanobacteria • Cross between a bacteria and algae • Some produce toxins, others do not • Blooms in water column of dams and lakes • Forms mats on stones in rivers • Many different types • Treated with activated carbon Whau Valley Dam 2015
Chemical and Physical • Generally not as immediate concerns as effects appear over long period. • Can be caused by addition of chemicals during treatment processes. • Often related to poor aesthetic quality of water. Iron, Manganese, Turbidity. • Can use up chlorine and shield micro-organisms from treatment processes.
Legislative requirements Health (Drinking-water) Amendment Act 2007 Water Supplier must take all reasonable steps to: • Protect the source of drinking water • Provide a wholesome water supply. Must take all practicable steps to: • Comply with the Drinking-water Standards of New Zealand Must • Prepare and Implement Water Safety Plans (formally Public Health Risk Management Plans)
Multi Barrier Approach surface water
Barriers on Groundwater/Spring Sources
Whangarei Water Supply Area Sources and Treatment
Whau Valley: Source Treatment & Distribution Barriers
General Risks • Contaminated Water Supply • Always a concern but multi barrier approach should reduce likelihood • Water Outages • More likely, multi barrier can increase risk of outages • Equipment failure/power outage/drought • Critical customers • Increased storage vs water quality
Risk Management It is always possible to put in place more barriers and add more redundancy to a system, thus reducing the risk of failure. However, this is not always practical or affordable. It is important to understand the level of risk associated with supplies. In order to standardize risk management within the water sector the Ministry of Health introduced a requirement for water suppliers to complete Water Safety Plans.
Water Safety Plans • Formally Public Health Risk Management Plans • Required for all Water Supply Areas • Risks are assessed from Catchment through Treatment process and Distribution Network. • Risks need to be addressed by • Eliminating – Often capital projects • Minimising – Process improvement • Response – Contingency planning
Emergency Response – Chlorine Leak Breathing apparatus training
Havelock North The incident at Havelock North in August 2017 and the subsequent inquiry have highlight a number of issues within the water sector. In light of this many water suppliers around the country are re- assessing their appetite for risk. Whilst a similar situation to Havelock North does not exist within Council’s supplies, improvements are recommended to ensure we maintain compliance with best practice and maintain risks at a reasonable level.
Maungakaramea bore security
New Projects As a result of the latest Water Safety Plan reviews and in light of the Havelock North inquiry findings the following new projects are recommended for inclusion in the first three years of the new LTP. • Ruddells WTP upgrade • SCADA upgrade • Fairway Drive Pump Station upgrade • Whau Valley New WTP Improvements • Site Security Improvements
Ruddells Water Treatment Plant Upgrade Possible Filter Risks - Increase in turbidity leads to ineffective treatment of Protozoa. (Beca Report March 2017) Recommendation - Installed filtration system Requirements - Additional land - Package plant - Increase opex costs Estimated Cost $1 million
SCADA Upgrade SCADA and telemetry systems are critical to running modern process facilities. Our SCADA system is now over 12 years old, it uses old technology and old software. The programming is out of date. Risks - Old systems fail and compliance is lost or non potable water is produced - Increase in opex costs due to callouts and breakdowns, systems no longer supported by suppliers. Recommendation - Update SCADA system and radio telemetry network. Requirements - Strategic plan of SCADA system - Selection of preferred hardware, software, communications systems - Design, installation, programming and ongoing maintenance. Estimate Cost $1-$2million between Capex and Opex
SCADA screen - Ruddells
Fairway Drive Pump Station Upgrade Fairway Drive Pump Station supplies water to the Northern part of the City including Kamo, Tikipunga and Hikurangi. There are 3 pumps in the building. When one pump is down, 2 pumps cannot meet peak demands. All three pumps are old. Risks - One pump failure could lead to loss of water to North of City Recommendations - Upgrade all three pumps with new pumps of increased capacity Requirements - 3 new pumps and variable speed drives - Improve health and safety access to pump chamber - Upgrade transformer to cope with increase demand - Investigate emergency power generation requirements Estimated Cost $500,000
Fairway Drive Pump Station
New Whau Valley WTP upgrade The new Whau Valley WTP was originally designed to be similar to the existing plant. However, investigations and plant trials are indicating that improvements to the treatment processes are required to ensure ongoing compliance. Risks - Algal blooms become more frequent and require treatment - THM levels exceed 0.5 of MAV or standards increase - Iron and Manganese cause dirty water in network Recommendations - Add new processes to treat these issues Possible Requirements - Powder Activated Carbon to treat Algae and reduce THM levels - Second stage filtration for Iron and Manganese removal Estimated Cost $2 million
New Whau Valley Pilot Plant trails
Site Security Upgrade All water treatment plant and reservoir/pump station sites still have access via keys and padlocks. Fences are basic chain fencing and only two water treatment plants are alarmed (buildings only). Access to sensitive sites needs to be better controlled, particularly where dangerous chemicals are stored. Risks - Vandalism, theft and potentially sabotage of water supply. - Poor records of who is accessing sites, relies on signing in. Recommendations - Upgrade security system to modern electronic access where applicable – align with SCADA system to improve efficiency. Requirements - Electronic Access for individuals, Alarm systems, CCTV Estimated Cost $500,000
Sargeants reservoir
Other potential new LTP Projects Renewals in conjunction with Roading Water Services work with Roading and NZTA to ensure mains are upgrade, where appropriate, during roading projects. This is for mains that would not be due under the prioritization/end of life model. Exact yearly funding to be confirmed in conjunction with Roading. Marsden Point Trunk Main This project will complete the new trunk main from the treatment plant to the Refinery. It will help reduce the risk of water outages to the refinery and also cater for growth in the Ruakaka One Tree Point Area. Estimate Cost $1.6million
Operational Risks Electrical/Mechanical Failure • Current run to failure strategy needs reviewing • Best for asset requires more proactive approach • Combination of sensible renewal strategy and effective maintenance schedules Professional Support • Increase in complexity, hardware and software (modelling) • New standards and compliance, incl Health and Safety • Technical advice and local support • Combination of in house and outsourced • Knowledge management • Continuous Improvement and Ongoing Training Other Risks • Backflow prevention • Leak Detection • Quality Control Operational budgets to be reviewed to include best for asset maintenance schedules and improved knowledge management.
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