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Water Services Asset Management Plans and Future Forecasts 10 July 2017
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What is Included in “Water Services”
Water Supply Dargaville/Baylys, Maungaturoto, Glinks Gully, Ruawai, Mangawhai Wastewater Dargaville, Maungaturoto, Glinks Gully, Kaiwaka, Mangawhai, Te Kopuru Stormwater Dargaville, Kaiwaka, Baylys Beach, Mangawhai, Te Kopuru, minor Land Drainage – multiple schemes
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Contribution to KDC Community
Water Services are fundamental to the health and welfare of the KDC community High quality drinking water and safe disposal of wastewater are fundamental to health Wastewater treatment protects the environment Stormwater and Land Drainage provides protection to property and life in storm events All are supporting infrastructure that facilitate ongoing operation of community, business and industrial enterprises
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What is Asset Management ?
‘AM is a process that provides a required level of service in the most cost-effective way through creation, operation, maintenance, rehabilitation and disposal of infrastructure assets for present and future customers.’ A number of desired, but potentially competing outcomes Focus is on service – assets are the tools A lot of choices i.e. no single solution
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Work smarter not harder Asset Management provides you with tools (IIMM) to work smarter
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IIMM: International Infrastructure Management Manual
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Influence on Council Planning / Funding
The Water Services use a lot of assets to provide the service (pipes, manholes, valves, pump stations, treatment plants) These cost a lot to construct, operate, maintain and manage These costs are reflected in the Annual Plan (1 yr), Long Term Plan (10 yrs) and Infrastructure Strategy (30 yrs) and costs are recovered from users
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Operating Costs (OPEX)
Some Key Definitions Operating Costs (OPEX) Typically the ongoing cost of managing, operating and maintain the assets including power, chemicals, interest costs, etc. Capital Costs (CAPEX) The cost of constructing new assets and upgrading/renewing existing assets Depreciation A reflection of the consumption of the assets by current users. One of several funding sources available for renewals
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Types of Capital Works Council is required to track three types of CAPEX expenditure : Renewals – Replace current asset when it reaches the end of its useful life Level of Service Change – Typically replaces an existing asset but provides enhanced service Growth – New, or larger, asset to provide for growth Some projects may contribute to all three
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Key Drivers For KDC CAPEX
Renewals Many of KDC’s systems will require renewal over the next 30 years Some renewals are already required Level of Service Change Customer expectations always increasing Legislation and Resource Consents becoming more demanding – nothing is getting easier! Growth Generally low levels of growth in west but relatively high in Mangawhai
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The Asset Management Plan
Contains an overview of all relevant information in relation to how the service will be delivered. Based on information & includes: Links to Community Outcomes Legislation and Levels of Service targets The assets utilised by type, age, condition, risk Issues impacting on the service Forecasts for OPEX and CAPEX Improvement Plan for next iteration
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Focus of Asset Management
Essentially has four primary focus areas : What is required? When is it required (ideally as late as possible)? How can the overall cost be optimised (short term vs long term costs)? How can it be delivered as efficiently as possible (how it is constructed, owned, operated, funded)? Finance focus on where the funding will come from and impact on rates Engineering and Finance work together
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Using Criticality to Manage Risk
Risk Management is a key aspect of asset management High Criticality assets have major impacts when they fail and ideally try to avoid this Low Criticality assets have minor impacts and can be allowed to fail until cost or level of service is unacceptable KDC Water Services has identified which assets fall into which category and utilise this information to manage assets and prioritise renewals
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Overall Water Services Coverage
Community Wastewater Water Stormwater Dargaville Mangawhai Partial Ruawai Maungaturoto Minimal Kaiwaka Te Kopuru Open Drains Baylys Beach Glinks Gully
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Overall Financial Commitment
Overall replacement value of assets utilised is $165 million Overall depreciation (consumption of those assets) is $2.7 million per year Overall cost of operating and maintaining the systems (excluding KDC staff and finance costs) is $4.2 million per year
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Water Services Share for 2017/18 Adopted 2017/18 Annual Plan
Service (Excl Finance) Operating Cost % of Total Whole of Council $31.6 Water Services $6.0 20% Wastewater $3.2m 10% Water Supply $1.7m 5% Stormwater $0.7m 2% Land Drainage $0.4m 1% These costs exclude Interest and Depreciation which will increase Water Services share of overall expenditure.
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Wastewater Dargaville WWTP
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Wastewater Service Key outcomes :
Removal of wastewater from connected properties Conveyance of wastewater across community without overflows Treatment to minimise impact on receiving environment and to safeguard health
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Wastewater Activities
Maintain collection network, clear blockages, etc. Operate and maintain pumpstations Operate and maintain treatment plants Obtain, renew and comply with Resource Consents for discharges Customer service Planning and Asset Management Delivery of CAPEX for growth, Level of Service change and Renewals
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A Note About Treatment The Wastewater Treatment Plants (WWTP) discharge to the environment Must achieve acceptable reduction in : Harmful micro-organisms (measured as E-coli) Suspended solids Demand for oxygen from the receiving water Nutrients that can encourage unwanted algal growth Difficult to achieve with simple ponds Trend is towards UV, membranes, advanced activated sludge, wetlands, etc.
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More about Treatment The wastewater treatment process also generates waste solids that are usually regarded as ‘contaminated’ For the pond based systems the solids build up in the pond and eventually need to be dredged, de-watered and disposed (10-20 yrs) For Mangawhai, sludge is separated by the treatment process, dewatered by belt press and disposed on an ongoing basis
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Wastewater Trends Traditional septic tanks and seepage beds unlikely to be acceptable. Now generally using aerated treatment processes, irrigators, etc. Collective failure of tank systems can lead to health and environmental concerns Collection systems now focused on minimising stormwater inflows using vacuum, small bore pumps or ‘new’ gravity systems
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Annual Depreciation (2014)
Wastewater Schemes Scheme Connections Replacement Value (2014) Annual Depreciation (2014) Mangawhai 1,956 $41.6m $801k Dargaville 1,960 $18.7m $329k Maungaturoto 369 $5.8m $125k Te Kopuru 190 $2.0m $38k Kaiwaka 163 $1.8m $33k Glinks Gully 24 $0.3 $6k TOTAL 4,324 $70.0m $1.3m 138 km of pipe - $16k of assets per connection Average asset life expectancy = 52 yrs
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Mangawhai Wastewater(North and South)
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Mangawhai Largely all new since 2000
Mix of standard gravity and small bore household pumps Sophisticated activated sludge treatment plant and land disposal Rapidly growing system but growth CAPEX should be developer funded
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Dargaville Wastewater
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Dargaville System goes back to 1944 Renewals starting to come through
Provides service to Silver Fern Farms meatworks Simple oxidation pond treatment with discharge to river
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Maungaturoto Wastewater
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Maungaturoto Most of system constructed in 1980
Renewals starting to come through Does not provide service to Fonterra Dairy Factory (independent) Oxidation pond treatment with membrane filtering and discharge to river
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Te Kopuru Wastewater
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Te Kopuru Most of system constructed in 1980
Renewals starting to come through Very simple system with no pumpstations. Uses oxidation pond and discharge to river
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Kaiwaka Wastewater
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Kaiwaka Most of system constructed in 1980
Renewals starting to come through Oxidation pond treatment and wetland with discharge to upper Kaipara Harbour
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Glinks Gully Wastewater
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Glinks Gully System constructed in 1989 Very small
Each house has a septic tank. Effluent is collected for disposal to a communal discharge field High peak loads over Christmas period
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Wastewater - Unserviced
Properties and KDC facilities not serviced by KDC schemes have individual onsite systems – mostly septic tanks These have varying degrees of effectiveness but no large community clusters causing problems KDC required to monitor overall health and environment of the district No new schemes being planned
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General Wastewater Issues
Understanding how pipes are deteriorating and when renewals likely to be required Managing (and reducing) infiltration and inflow into the networks Improving knowledge of assets and their performance – particularly using CCTV De-sludging of oxidation ponds Ensuring ongoing acceptability of pond based treatment (multiple sites)
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Life Expectancy of Wastewater Pipes
Previous estimations of renewals used a 40 year life expectancy for AC pipes This generated a backlog of ‘Overdue’ renewals of some $1m This is now regarded as overly pessimistic as it is not evident that these pipes have failed This forecast is based on a 60 year life expectancy
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Specific Wastewater Issues
Mangawhai Providing for ongoing growth – Scenario 2 used. Expectation that this will be largely funded either by developers doing the work or by contributing to growth related costs Cost of operation after contract expiry in Likely to decrease but extent of change not known at this time and depends on negotiations. No change included at this time
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Specific Wastewater cont
Dargaville Infiltration and Inflow into network. Worst in WaterNZ National Performance Review Providing for peak wet weather flows – P/S 1 and 2 upgrading Desludging lagoon – It is currently 80% full and this compromises its treatment capability. $2m split over 2018/19 and 2019/20. This will be OPEX as it just restores original capacity. However it could be funded over several years to avoid OPEX spike
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Specific Wastewater cont
Maungaturoto Renewal of WWTP membranes Investigate P/S storage for storm flows Te Kopuru Future desludging of lagoon but not currently inside 10 years Some non-compliance with ammoniacal nitrogen (nutrient) levels in discharge
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Specific Wastewater cont
Kaiwaka System at capacity and no new connections allowed Install curtain wall in pond to address non- compliance for coliform discharges Glinks Gully Consideration of extending the scheme Consideration of options for renewing the soakage field
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OPEX and CAPEX Forecasts for Wastewater
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OPEX – Wastewater Spike is de-sludging of Dargaville pond - $2m over 2 years
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CAPEX Forecasts – Wastewater Lines and Points
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CAPEX - Dargaville Lines
EW from 1944 Dargaville dominates early pipe renewals within next 15 years. Later peak is due to Maungaturoto, Kaiwaka and Te Kopuru all coming due around 2040
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Wastewater Plant CAPEX
$5m Pumps, switchboards, etc have much shorter lives Dargaville is mostly pumpstations Note large spike for Mangawhai (10-20 years) due to highly mechanised system
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Overall Wastewater CAPEX Bars are proposed, lines are LTP 2015
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The Big Drivers of Change
Four items explain most of the difference and the high cost in yrs 1-3 Mangawhai growth provision (Scenario 2) Renewal and reconfiguration of Dargaville P/S 1 and 2 to contain stormwater infiltration Provision for modelling, investigations and design Review of timing of renewals Also note - Rapid increase in pipe renewals just outside 10 year window
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Key Projects Year 1-3 Community Project $ in Period Dargaville
Upgrade P/S 1 & 2 $2,030k Mangawhai Upgrades & growth $4,480k Maungaturoto WWTP renewals $300k All Modelling, condition assessment $640k
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Water Supply Ruawai WTP
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Water Supply Service Key Outcomes
Reliable supply of water during normal and drought conditions Dependable water quality Sufficient pressure for normal customer usage Fire protection via hydrants and sprinkler systems
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Water Supply Activities
Manage and maintain raw water sources Operate & maintain water treatment plants Maintain distribution network, repair breakages, leaks, hydrants, etc Operate and maintain pumpstations, reservoirs, etc Manage Back-flow prevention Obtain, renew and comply with Resource Consents for water takes
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Water Supply Activities Cont
Extensive water quality testing & reporting Customer service Consumption billing Planning and Asset Management Delivery of CAPEX for growth, Level of Service change and Renewals Access to water for tank top-ups Note – You are not paying for the water itself, just the capture, treatment and delivery
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A Note About Treatment All water delivered is required to comply with Ministry of Health : Drinking Water Standards. This covers : Micro-biological (viruses, giardia) Harmful chemicals (natural and man-made) Aesthetic (taste, clarity) Chemical correction (pH, hardness) Fluoride (optional and not used in KDC)
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Treatment Processes A multi-step process used :
Management of raw water catchment where possible Filtration to remove particles and many contaminants (flocculation to bind together) Disinfection to kill micro-organisms Residual disinfection in the reticulation system to protect to point of use Trend is to UV, membranes and advanced technologies that can treat colour and taste e.g Activated Carbon – but not yet in KDC
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Water Supply Trends Key drivers are quality, reliability and efficiency Water quality is highly regulated and monitored Climate change driving concerns about long term and seasonal reliability of supply Expectation that any water take is used efficiently with water efficient appliances and an acceptably low level of leakage
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Annual Depreciation (2016)
Water Supply Schemes Scheme Connections Replacement Cost (2016) Annual Depreciation (2016) Dargaville / Baylys 2,782 $43.6m $673k Maungaturoto 447 $14.1m $233k Ruawai 251 $3.2m $74k Glinks Gully 85 $0.5m $9k Mangawhai 18 $0.4m $10k Totals 3,583 $62.0m $999k 175km of pipe - $17.3k of assets per connection Average asset life expectancy = 62 yrs
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Dargaville Water Supply
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Dargaville Pipework goes back to 1950
Single supply line out to Baylys Beach Long single raw water supply line from the Waipapataniwha catchment up north and from the Kaihu River Drought resistance requires consideration
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Overall Dargaville Schematic
Usual source is Waipapataniwha intakes If Rotu intake used water must be released from Waiatua Dam to maintain stream flow Proposal to directly connect dam to raw water pipeline
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Maungaturoto Water Supply
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Maungaturoto Most pipework installed 1965
Long raw water pipelines from Brynderwyn from dams and springs Raw water supply to Fonterra dairy factory
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Ruawai Water Supply
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Ruawai Most pipework installed 1974
Water supply from bores in riverbank First supply marginal and depends on pumps
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Glinks Gully Water Supply
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Glinks Gully Most pipework installed 1996
Very small system sourced from three springs Struggles to cope with peak demand over summer
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Mangawhai Water Supply
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Mangawhai Not really a public supply. Water goes to motor camps and some commercial Introduced in 1996 Water sourced from bore Recent upgrade to treatment No reticulated fire protection for community
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Cartridge filtration and UV disinfection
New Mangawhai WTP Cartridge filtration and UV disinfection
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Award Winning Engineering
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Water Supply - Unserviced
Properties not serviced by KDC schemes have individual onsite systems – mostly rain tanks and bores. Also some KDC sportsgrounds, WCs etc. These have varying degrees of drought resistance and quality KDC required to monitor overall health and environment of the district No new schemes being planned at this time
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General Water Supply Issues
Understanding how pipes and facilities are deteriorating and when renewal will be required. Pressure pipe is much more difficult to survey than gravity which can be CCTV inspected Maintaining compliance with Drinking Water Standards. Increasingly difficult for giardia and cryptosporidium Renewal of short lived treatment assets Providing for demand under drought conditions
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Specific Water Supply Issues
Dargaville Review drought sensitivity of sources Continue renewal of supply to Baylys Commence renewal of raw water supply pipe Planning for pipe to Waiatua Dam ($3m) Large pipe under Dargaville H.S. Backlog of watermain renewals Maungaturoto Continue renewal of raw water supply lines
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Specific Water Supply Issues
Ruawai Review condition of bores Review condition of reservoir Glinks Gully Review source, treatment and storage capacity under peak summer demand (currently supplementing with tanker)
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Specific Water Supply Issues
Mangawhai New treatment system recently installed Peak demand pressures from motor camps Community is largely unserviced and no reticulated fire protection
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OPEX and CAPEX Forecasts for Water Supply
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OPEX – Water Supply Much of increase in budget relates to Management Services which includes condition assessment, asset data gathering, Water Safety Plans etc and will be ongoing for the 10 years
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CAPEX Forecasts – Dargaville Watermains
Dargaville showing backlog of overdue renewals and then large future spike of AC pipes
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CAPEX- Non-Dargaville Watermains
Renewal of non-Dargaville systems well out into future
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CAPEX Forecasts - Water Plant
Includes treatment plants, pumpstations, reservoirs Prediction based on expected lives in 2016 valuation Overdue requires further review to confirm actual condition
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Overall Water CAPEX 2019 allows $640k for watermain under school
2023 and 2024 allow for $3m connection to Waiatua Dam Overall - not significantly different to LTP 2015
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Key Projects Year 1-3 Community Project $ in Period Baylys Beach Renewal of supply line $300k Dargaville Connection to dam $3,000k Main under school $640k Raw Water renewals $1,160k Maungaturoto Raw Water renewal $450k All Modelling, condition assessment $485k There is a significant increase for specific projects over this period compared to the ‘background’ level of renewals
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Stormwater
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Stormwater Service Key Outcomes
“Nuisance’ stormwater effectively drained from properties without flooding occurring Larger storm events managed to avoid flooding of habitable floors and business Quality of stormwater managed to reduce impacts on the environment (aspirational target) Natural waterways retained and incorporated into urban amenity (aspirational target)
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Stormwater Activities
Maintain piped and open channel collection network, clear blockages, etc Obtain, renew and comply with Resource Consents for discharges Customer service Planning and Asset Management including allowing for ‘Climate Change’ Delivery of CAPEX for growth, Level of Service change and Renewals
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Stormwater Trends Traditionally, stormwater was primarily managed with a focus on avoidance of flooding Increasingly the emphasis is on also managing the quality of the stormwater and the impact of this in the receiving environment Also emphasis on retaining natural systems (open streams) and bio-diversity and making this an amenity for community
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Annual Depreciation (2016)
Stormwater Schemes Scheme Replacement Value (2016) Annual Depreciation (2016) Dargaville $23.0m $231k Mangawhai $7.9m $93k Baylys $.4m $14k Kaiwaka $0.4m $5k Te Kopuru $0.3m $1k Maungaturoto $3k Other $1.0m $12k Totals $33.3m $360k 63 km of pipes, 47km of open drains Average asset life expectancy = 92 yrs
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Dargaville Stormwater
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Dargaville Some flooding regularly occurring in low lying areas
Open drains still the main system in parts with maintenance and access issues Potential exposure to flooding from high river levels
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Mangawhai Stormwater
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Mangawhai Extensive use of open drains and limited coverage in area subject to growth and redevelopment
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Baylys Beach Stormwater
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Baylys Beach Parts of community not served with ‘formal’ system
No particular issues
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Kaiwaka Stormwater Minimal system
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Te Kopuru Stormwater
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Te Kopuru Entirely open channel system
Provides for cost minimisation if this is an acceptable Level of Service
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Maungaturoto Very small network with replacement value less than $300k
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General Stormwater Issues
Information about assets is incomplete and unreliable Many systems are old, relatively ‘informal’ and without defined level of service Has suffered from low profile in the past with little condition assessment or renewal activity
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Specific Stormwater Issues
Dargaville Catchment Management Plan required Exposure to flooding from high Wairoa River levels Some open drains through private property are quite deep Mangawhai Pressure on system from development Town Plan indicates substantial upgrade required
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Specific Stormwater Issues
Other systems All needing Catchment Management Plans but lower priority than Dargaville and Mangawhai Asset information needs improvement to enable proper renewal planning
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OPEX and CAPEX Forecasts for Stormwater
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OPEX –Stormwater Initial increase is for Asset Information discovery
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CAPEX Forecasts - Stormwater
Information on installation date, and/or condition, held by KDC is very low reliability Cannot be used to generate a reliable estimation of long term renewal profile Proposed investment in gathering information over next three years However, there projects that are known to be required
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Overall Stormwater CAPEX
Level Of Service (LOS) includes $500k each year for Mangawhai per ‘Town Plan’
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Key Projects in Year 1-3 Community Project $ in Period Mangawhai
Town Centre Plan $1,500k Dargaville Pipe renewals $300k Baylys Beach $340k
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Flood Protection and Land Drainage
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Land Drainage Service Key Outcomes :
Lowering watertables to allow productive farming use of low-lying ground Managing drainage of storm events to minimise disruption to production and damage Protection of low-lying land from high river and harbour levels
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Land Drainage Activities
KDC provides a limited service in this activity and is mainly maintenance focused Much of the expenditure and activity is undertaken by Drainage Committees for the particular scheme of the owners of the property concerned.
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Land Drainage Schemes The main scheme is Raupo in the Ruawai vicinity
There are 28 other schemes varying widely in size
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General Land Drainage Issues
Overlap of responsibilities, and lack of clarity, between KDC, Northland Regional Council and Drainage Committees Land Drainage Committees operate with varying levels of involvement – Raupo (Ruawai) the most active
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OPEX and CAPEX Forecasts for Land Drainage
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OPEX – Land Drainage
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CAPEX – Land Drainage $320k of Raupo in 2018/19 is renewal of Bellamy, Double Creek and North Ash floodgates
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Key Projects in Years 1-3 Community Project $ in Period Raupo Floodgates and stopbanks renew/rehab $550k District-wide Floodgates renew $90k Historically KDC has made little investment into Land Drainage It is anticipated that more activity will be required in the future to ensure the Land Drainage schemes remain viable and functioning
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Conclusions Kaipara District Council Water Services are characterised by multiple small schemes with no interconnections or economies of scale Only significant growth is in Mangawhai All water and wastewater schemes (except Mangawhai wastewater) utilise simple, but somewhat dated technologies Some systems are relatively old but many are relatively new reflecting significant community service upgrades at that time
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Conclusions cont Some significant renewal requirements for pipelines are emerging plus ongoing renewals for the shorter lived plant and equipment Keeping up with legislation and resource consent requirements for water and wastewater will be an ongoing challenge and difficult to predict at this time KDC funding of Mangawhai wastewater closely tied to contributions received from developers
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Conclusions cont A significant issue is the quality of the information about the assets and their condition. This is not uncommon in NZ and funding is provided for ongoing collection of data and condition information Hydraulic modelling of water and wastewater networks and catchment management planning (stormwater) is particularly needed for Dargaville and Mangawhai to ensure that appropriate solutions are put in place
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Conclusions cont The proposed OPEX and CAPEX seeks to address these issues in a timely but pragmatic manner The proposed programme identifies when the works are ideally required. This must be overlaid with funding capability to determine that achievable programme. This may require some compromise, or redefinition of the desired level of service
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Conclusions cont Given the above considerations the forecasts presented are the best that can be generated with current knowledge at this time Refinement and optimisation will continue over next few months together with input from Finance regarding availability of funds to provide for the inevitable peaks and the underlying trends
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