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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 ContentPublic Health Contaminants, legislation & standards (DWSNZ), multi-barrier approachOur Water Supply Our sources, treatment and distribution systems
Risk Management General Risks Water Safety Plans Havelock North New Projects Operational Risks
Existing LTP Projects Condition assessments and renewals
FinancialLevels 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
time hrs bacteria0 11 642 4,0963 262,1444 16,777,2165 1,073,741,8246 68,719,476,736
E.Coli magnified 15,000 times
doubling every 10mins
From human or animal faeces. E-coli used as an indictor of probable presence.Removed by coagulation and filtration, destroyed 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 2007Water 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 ZealandMust • Prepare and Implement Water Safety
Plans (formally Public Health Risk Management Plans)
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
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.
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
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 costsEstimated Cost $1 million
Possible Filter
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
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 CityRecommendations- Upgrade all three pumps with new pumps of increased capacityRequirements- 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 requirementsEstimated Cost $500,000
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 networkRecommendations- Add new processes to treat these issuesPossible Requirements- Powder Activated Carbon to treat Algae and reduce THM levels- Second stage filtration for Iron and Manganese removalEstimated Cost $2 million
Site Security UpgradeAll 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, CCTVEstimated Cost $500,000
Other potential new LTP Projects
Renewals in conjunction with RoadingWater 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 MainThis 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.
Whau Valley Dam Chimney drain upgrade
Construction completed in 1969 holds 1.9 million cubic meters
Chimney drain upgrade cost $2.6M
Watermain - breaks and performance issues
Output of Hansen Decision model and hydrant flow testing
Watermain renewals prioritised on based on poor performance
Years 1 -3 Years 4-10 total
Leaks breaks & condition $6.5M $1.8M $8.3MFlow & pressure $5.3M $7.3M $12.6M
Total for Poor Performance $11.8M $9.1M $20.9M
2015 LTP budget projected 2018 to 2028
$7.3M $25.8M $33.1M
End of expected life $20.1M $19M $39.1M
Prioritisation based on Number of breaks >5 in 3 years are planned for Y1-3 Condition rating of very poor planned Y4 onward Failed hydrant test replaced at end of expected life End of life mains without problems not expected to be replaced with
projected budgets “sweating the assets” until performance issues arise
Aging Assets
On average Water assets are half way through the expected life
Water Asset groups
% of Asset value
Replacement
Current value
Ave life remain-ing
WTP Assets 15% $51.8M 28.4M 55%
Reservoirs 15% $52.3M $32.5M 62%
Reticulation network
68% $237.7M $118.4M 50%
Water meters 3% $10.1M $5.6M 56%
Total $352M $185M 53%
Data from 2014 AECOM revaluation % expected to stay the same
39
28
54
73
39 43
179
141
15
2
27
95
< 3 Y E A R S L IFE 4 - 1 0 YEA RS 1 0 - 3 0 YEA RS > 3 0 Y EAR SKM
S
WATERMAINS EST IMATED REMAINING LIFE
Rider Distribution Trunk
AMP Capital Projects Years 1-3 LTP $26.8MProject Cost Date Driver Risk
Whau Valley Chimney Drain $2.6M 2018/19 Not to current Stds High
Ruddells WTP upgrade $1M 2018/19 Contamination risk Med
SCADA upgrade $1M 2018/20 Control failure High
Fairway Pump station upgrade $0.5M 2018/19 High demand Med
New Whau Valley WTP 2nd stage $2M 2018/19 Disinfection byproducts Med
Site security upgrade $0.5M 2019/20 Sabotage MedReticulation renewals $11.8M 2018/21 Poor performance HighMeter renewals $0.9M 2018/21 Lost revenue Med
Station Rd trunk upgrade $0.8M 2019/20 Growth Totara Park Med
Vinegar Hill trunk upgrade $1.4M 2020/21 Growth Tikipunga MedThree Mile Bush Reservoir $1.2M 2020/21 Growth 3 Mile bush MedWaipu trunk upgrade $0.8M 2020/21 Growth Waipu Med
WTP equipment upgrades $1.3M 2018/21 Poor performance HighMain renewals with Roading $0.6M 2018/21 Reduced cost MedWater tanker & filling sites $0.4M 2019/20 Emergency supply Low
AMP Capital Projects Years 4-10 LTP $58.3MProject Cost Date Driver Risk
Dip Rd Reservoir $2.2M 2022/23 Capacity/growth Med
Waipu Reservoir $1.3M 2023/24 Capacity/growth Med
Maungakaramea Reservoir $0.6M 2024/25 Capacity/growth Low
Ruakaka Reservoir $0.8M 2026/27 Capacity/growth Med
Sargeants Reservoir & trunk $1M 2026/27 Capacity/growth Med
Fairway Drive Reservoir $0.8M 2027/28 Capacity/growth MedReticulation renewals $21.3M 2022/28 Condition & capacity HighMeter renewals $2.4M 2018/21 Lost revenue Med
Otaika to City trunkmain $4.4M 2022/25 Supply security Med
Poroti trunkmain $1.4M 2022/24 Supply security MedOnerahi trunkmain $2.6M 2024/25 Supply security MedMarsden Point trunkmain $1.6M 2024/25 Supply security Med
Mains with Roading $1.4M 2022/28 Reduced cost MedWairua River Source/treatment- Poroti $13M 2024/27 Drought supply HighWTP Equipment $3.5M 2022/28 Performance High
AMP Opex Projects Years 1-10 LTP $15.8M
Project Cost Date Driver Risk
Reservoir Rehabilitation $2.2M 2018/28 Condition Med
SCADA upgrade $1M 2018/20 Control failure High
Pipe-bridge re-coating $60K 2018/22 Condition Low
Engineering services $1M 2018/28 Projects High
Media & UV replacements $2M 2018/28 Compliance High
Professional services $1M 2018/28 Compliance MedCapital Project Opex component @10%
$8.5M 2018/28 Prudence
Water Finances
Where should we be heading?
-$15,000,000
-$10,000,000
-$5,000,000
$0
$5,000,000
$10,000,000
$15,000,000
$20,000,000
2014
-201
5
2015
-201
6
2016
-201
7
2017
-201
8
2018
-201
9
2019
-202
0
2020
-202
1
2021
-202
2
2022
-202
3
2023
-202
4
2024
-202
5
Water Debt Profile (inflated)
Closing balance Grey in credit Red in Debt
CAPEX spend inflated
TRIM 14/54728
Current Level of service
We wish to change these?
Involves:• Simpler statements• Additional customer response• Consultation as part of LTP• Status quo or more
aspirational LoS and targets?
Council will provide safe drinking water with adequate pressures to the residents of the District connected to the water supply system
The water supply system is managed in a sustainable way and in times of emergency there is adequate water supply available
Proposed Level of Service changes
New LoS statements
Recommend: We change the wording & add in new LoSLeave the performance measures and targets as is for now.Mandatory measure not used for LoS. Are reported separately.
Community OutcomesEarly engagement planned this may effect LoS
2018 Levels of Service - Water
Our customers receive safe drinking water
Water is supplied continuously with flow and pressure adequate for customers’ use
Customer requests are responded to promptly
In times of emergency there is water available
We manage the water supply system in a sustainable way that also caters for growth
Planning for Growth
• Current capacity maps (excess or below EES)
• Hydraulic Model recalibration
• Consent applications & Plan changes
• Development contributions
• Review of 30:50 projects & timing
• Water Master Plans (Network boundaries)
• Water demand forecasting & climate change
Climate Change
• Potential issues that may occur as a result of Climate Change• Increase frequency of droughts, more severe• Increase in demand• More algal blooms• More severe weather events causing flooding and damage to facilities• Sea level rise may impact existing sources.
The most immediate concern is the increase in frequency of Algal blooms. This may require some improvement in treatment process in the short term. Other impacts of climate change will need to be monitored and catered for in future LTPs
Fluoridation
• Bill currently going through Parliament• Likely that DHBs will be given power to decide• Estimated capital cost $1.5M to upgrade all WTPs• Increase in Opex of approximately $100,000 per year• Potentially some Government funding• It is not proposed to make an allowance in this LTP for
Fluoridation
Summary
The focus of this LTP period for Water will be;• Commitment to Protecting Public Health• Ensuring compliance of all WTPs• Reducing risk of failure
• SCADA and security• Mechanical – pumps and WTP equipment• Reticulation – watermains and trunk mains• Whau Valley Dam
• Allowing for Growth - planned projects• Improved Management
• Expertise professional services & operators• Better condition assessment• Legislative compliance, H&S • Knowledge management
These topics will be the main emphasis of the 2018 AMP