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5-Waters Volume 1
8 Infrastructure Sustainability
This section describes the processes used by the Council for assessing and managing sustainability for the 5Waters Activity and its integration with Council's other activities. Infrastructure sustainability is a core part of the Council's vision for successful asset management. This section also addresses the possible implications of climate change and energy requirements relating to the 5Waters activity.
8.1 Sustainability Principles and 5Waters Levels of Service
The Sustainability Principles adopted by Council are inherent in the Levels of Service developed for the 5Waters Activity. The principles are as follows:
- Make decisions based on the four aspects of well-being
- Observe the Precautionary Principle to provide contingency and enable adaptability of our community
- Seek “intra-generational" and “inter-generational" equity
- Internalise environmental and social costs
- Foster community welfare
- Act to halt the decline of our indigenous biodiversity and maintain and restore remaining ecosystems
- Consider, and promote the sustainability of our neighbouring communities and work with governing bodies for sustainable outcomes
The connections and interactions are many and complex, and occur on different levels. Some key relationships are elaborated on in Table 8‑1.
Table 8‑1 Relationship between Levels of Service and Principles
Level of Service
|
1 |
2 |
3 |
4 |
5 |
6 |
7 |
1
| The community is provided with water services to a standard that protects their health (social well-being) and property (economic well-being)
| Y
| | | | Y | |
|
| 2 | Customers are provided (social) and fairly charged (economic) for water services that meet their reasonable needs | Y | | Y | Y | Y | | |
| 3 | Nuisance effects of water services are minimised (social and economic) | Y | | | | Y | | |
| 4 | Water services are provided in a cost effective manner (economic) | Y | | | | | | |
| 5 | Problems with water services are addressed in a timely manner and prioritised according to risk and need (social, economic, environmental) | Y | | | | | | |
| 6 | Service capacity is provided to accommodate growing communities, where this growth is sustainable (social, economic, cultural, and environmental) | Y | | Y | | | | |
| 7 | Adverse effects of water services on cultural and heritage values are minimised (cultural) | Y | | | | Y | | Y |
| 8 | Adverse effects of water services on the environment are minimised (environment) | Y | | | | | Y | Y |
| 9 | Greenhouse gas emissions from the provision of water services are minimised (environment) | Y | Y | | | | | Y |
8.2 Sustainable Development
Sustainable development focuses on the concept of intergenerational equity whereby the decisions and actions of an entity need to balance the needs of present and future generations. Consideration of four well-beings (economic, social, environmental and cultural) is essential in a sustainable development approach. From an asset management perspective, taking a sustainable approach is critical as many assets have long service life, therefore maintaining or future proofing these assets to meet the needs of current and future generations is necessary.
The 5Waters activity areas must be sustainable in a way that:
- Does not exceed limits i.e. the resource will not be exhausted;
- Does not cause pollution;
- Does not generate unacceptable waste; and
- Focuses on equitable distribution of resources
Sustainability will be incorporated in strategic planning by both aligning strategic goals with sustainability concepts as well as incorporating the concepts in operational processes. Sustainability planning is important to asset management in ensuring that infrastructure services can facilitate the achievement of community well-beings. This means that our future communities will place at least as much value as we do on:
- Unfettered access to clean drinking water;
- Land to discharge treated wastes especially wastewater effluent or wastewater;
- Suitable ground and water courses (drains) to treat and discharge stormwater and land drainage water; and
- Water races which provide multiple biodiversity and social needs.
8.2.1 Water Resources within the Selwyn District
Selwyn District has access to water resources in the Upper Selwyn, Waimakariri and Rakaia rivers and ground water (confined and unconfined). Prior to early 2004 the ability to obtain resource consents to take water was viewed as a certainty. In 2004 Environment Canterbury introduced zoning to indicate the estimate of groundwater available and allocation limits. This was prompted by concerns from Environment Canterbury over significant increases of groundwater usage in many areas over recent years, as well as the preparation of the Natural Resources Regional Plan (NRRP), which addresses water allocation issues.
Groundwater resources in the Selwyn–Waimakariri and the Selwyn-Rakaia zones are considered to be fully allocated (overallocated). These are referred to as 'red zones'.
The implications of the District having over allocated zones are:
- In general, further groundwater takes will be considered as non-permitted activities, however consents will continue to be granted for community drinking water supplies;
- Future resource consents will be difficult (dollar cost and time) to obtain;
- Costs to obtain consents will be significantly higher with the applicant required to show that there is no significant effect on other water users;
- The consenting authority will require demand management practices to be implemented as part of the consent conditions; and
- The NRRP (Chapter 5 – WQN26) stipulates a maximum of 250 litres per day for human consumption when the water resource is at a low level. Management of usage at this low level is difficult if not impossible with existing demand requirements, scheme configurations e.g. no storage, community expectations and Health Act requirements.
Council proposes to build a reasonable use model for water consumption. This model would assess how much water is reasonable to use on each property connected to their water supply schemes. It will take into account domestic water use, parks and reserves water use, industrial water use and stockwater. Aqualinc Research Ltd were engaged to develop a model of this for the Selwyn District. This model will enable the Council to measure environmental impacts and implement demand management measures to ensure water used by ratepayers in not in excess of that which is deemed reasonable. The implemenation of this model in the GIS system is listed as an improvement item.
8.2.1.1 New Start for Freshwater
In 2005, the Government embarked on a Sustainable Water Programme of Action, coordinated by the Ministries for the Environment, Agriculture and Forestry to determine how to use, protect and preserve water in a responsible and fair manner. From 2008, with a change in government this became the “New Start for Freshwater" and culminated in 2011 with a National Policy Statement on Freshwater management.
8.2.1.2 Initiatives for 60 Year delivery of 5Waters
The 5Waters services will experience different demands over the next 60 years during population and demographic changes. While the district continues to consistently experience growth, the Council must be mindful that this may not always be the case. Six sustainability initiatives have been identified and whether they relate to growth and/or decline in the district is identified in Table 8‑2.
Table 8‑2 Sustainability Initiatives
1
| Closely monitor growth and demand – with just in time provision of infrastructure – pipe networks, facilities | Y
| Y
|
| 2 | Monitor the condition of land affected by disposal of waste (stormwater, wastewater) to ensure good health | Y | Y |
| 3 | Monitor condition and quality of public water and stock water, with trigger levels set against standards. Develop “what if" action plans to address reducing water quality where encountered | Y | Y |
| 4 | Delivery of robust asset condition profile with renewals profile – funding in place to replace | Y | Y |
5
| Secure resources e.g. public water for community growth expectations, with strong focus on wise use of water / reuse
| Y | |
6
| Work with agencies to deliver overarching cohesive solutions to water catchment issues, funding and resourcing where appropriate | Y | Y |
These initiatives will be reflected in asset management and the operations of water services assets.
8.2.2 Future Development and Council Expectations of Developers
Sustainability in the lifecycle management of 5Waters services requires that all parties involved in its management carry out appropriate analysis and play their part.
In the case of developers, who provide 5Waters services via the subdivisions they create - delivery of poor quality, high operation cost assets leaves an intergenerational legacy of issues. These include early renewals and high operations costs.
Developers should carefully analyse and report to Council via both legislative processes on the lifecycle robustness, operation and replacement of their proposed work, including:
- RMA – land use and subdivision consent;
- Subdivision guidelines;
- Off-site (Council) and Onsite (wider development) capacity;
- LGA – engineering plans;
- Infrastructure materials;
- Installation techniques, ground type including surface soil moisture capacity;
- Recycling and Reuse – stormwater, water races, wastewater (grey water); and
- Operational and maintenance costs.
Council expects to undertake discussion with and receive appropriate information from developers in relation to the matters above. Its role is to confirm that vested development driven assets are fit for immediate and long term community needs. The same approach is also allied to Council delivered assets, including the Eastern Selwyn Wastewater Scheme.
8.2.3 Financial Sustainability
Financial sustainability is the concept of securing stable and sufficient long-term funding and allocating it appropriately to ensure the costs of maintenance and upgrades of infrastructure are covered. This is an important concept of asset management as infrastructure should not be invested in if it is not sustainable to maintain and operate in the long term.
Financial sustainability can be utilised in asset management by incorporating these three concepts:
- District wide rates;
- Integration of schemes; and
- Shared projects.
8.2.3.1 District Wide Rates
The Council introduced district-wide rates in 2015 for water, wastewater and stormwater schemes. This means that most people pay the same for these services, no matter where they live. This change in rating structure has helped keep these services affordable for smaller communities and recognises that service standards are increasingly being determined by government legislation and regulations.
The Council is proposing to introduce a new rating structure for the water race network, based on a standard district rate. There are currently three water race schemes within the district: Ellesmere, Malvern and Paparua. Over the past five years, however, substantial changes have been identified which are expected to change the need for and use of the schemes. These include Central Plains Water irrigation scheme and changing drivers for the current and future use of the water race network. Alongside these factors, the rating base of water race users is declining, and many of the assets in the system are ageing and nearing the end of their useful life. Although the demand for water races to supply water for livestock is declining, water races bring other benefits to the Selwyn community. These include environmental benefits such as providing a water source for wildlife, and habitat for some endangered species, along with aesthetic benefits to many townships and residential areas. This proposed new structure will ensure that land owners who benefit directly from access to water races still fund the majority of the costs, but that the wider community also contributes to the costs. Over time, as the traditional use of water races for farming declines, the wider community will pick up an increasing proportion of the costs.
The Council is proposing to review the rating structure of the Land Drainage activity during the period of this LTP. This is due to the increasing number of issues emerging for the land drainage schemes.
8.2.3.2 Integration of Schemes
The Council has a number of small water schemes, however with the growth in the district, it may be possible to connect some smaller water supplies to larger schemes. This will lower the cost of providing services and ensure financial sustainability in the long term.
Scheme integration within the district to be investigated is:
- Connecting Edendale Water Supply to West Melton;
- Connecting the Johnson's and Jower's Road supplies to the West Melton supply; and
- Connecting some of the Darfield network to the Sheffield network.
The Branthwaite Drive water supply was integrated into the Rolleston scheme in late 2014. Armack Drive and Burnham water supply were connected to the Rolleston scheme in July 2015.
8.2.3.3 Shared Projects
Shared projects are projects that resolve issues across one or more of the schemes or 5Waters. These projects are currently funded across all schemes they provide benefit to. For example, providing education, improving AMS functionality and running asset valuations.
8.2.4 Environmental Projects
A significant proportion of the 5Waters AcMP is implemented through projects. These projects have been gathered during the plans development and approved from 1 July 2018. As mentioned above, shared projects are projects that resolve issues across one or more of the schemes or 5Waters. Environmental initiatives where taken will be implemented through shared projects. Examples of project work that is focussed on sustainability and environmental outcomes are:
- Establish a water quality monitoring program for land drainage schemes;
- Obtain a Global consent for land drainage activities;
- Prepare a stormwater catchment management plan; and
- Develop a water supply strategy.
8.2.5 Impacts of other Activities
5Waters sustainable asset management cannot occur in isolation from other services. The interactions of other services are identified below:
- Transportation: Stormwater conveyance and treatment to maintain trafficable surfaces and utilisation of common corridor for off-site services.
- Community Facilities: Water supply for sports fields and council houses.
- Social Services: growth needs and lifelines response during emergency events.
- Environmental Services/Planning and Building: Advice sought on capacity, cost and timing (availability) of service e.g. water supply.
- Corporate Services: Impose contributions, fees and charges. Identify non-rated properties where rating should occur.
8.3 Climate Change
The Resource Management Act 2004 Amendment Act defined climate change as “a change of climate that is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and that is in addition to the natural climate variability."
Council's 5Waters Strategy has identified that:
“Council will proactively undertake studies to better quantify the potential impacts of climate change on demand and availability as it affects the district."
It is necessary to consider climate change issues in relation to the 5Waters activity to ensure the sustainability of this activity and maintain the agreed levels of service. Climate change in relation to level of service are presented below in Table 8‑3.
Table 8‑3 Key Level of Service Linkages
The Community is provided with water services to a standard that protects their health and property
| Failure to recognise and respond to potential climate change implications may compromise Council's ability to continue to provide safe drinking water and adequate drainage systems. |
| Customers are provided with and fairly charged for water services that meet their reasonable needs | Failure to recognise and respond to potential climate change implications may compromise Council ability to provide for reasonable needs of customers in the future. |
Nuisance effects of water services are minimised
| Climate change may cause additional nuisance effects in the future. These can be minimised by understanding and planning for climate change and implementation of proactive measures. |
| Water services are provided in a cost effective manner | A proactive approach to mitigation of future climate change effects will generally be more cost effective than a reactive approach when problems become evident. |
| Problems with water services are addressed in a timely manner and prioritised according to risk and need | Climate change is a key risk and should be considered in a risk management context. |
| Service capacity is provided to accommodate growing communities, where this growth is sustainable | Climate change may impact on demand and service capacity and needs to be considered in infrastructure capacity planning. |
| Adverse effects of water services on cultural and heritage values are minimised | If the impacts of climate change are not recognised, there is a risk that cultural values may be compromised – for example, where stormwater treatment capacity is exceeded by more intense storms. |
| Adverse effects of water services on the environment are minimised | Climate change impacts on environmental conditions (eg water availability) may require modification of existing activities (eg water takes) to minimise future impacts on the environment. |
| Greenhouse gas emissions from the provision of water services are minimised | Climate change could affect the mix of energy used by the activity
|
8.3.1 Implications for the Selwyn District
In 2016 a climate change study was commissioned to investigate the impact of climate cycles and trends on Council assets. The assessment looks out 32 years from 2018-2038 aligning with the 2018 Infrastructure Strategy and was undertaken by Aqualinc Research Ltd.
The assessment is a high level risk assessment, to identify the assets that are most likely to be affected by climate change. Priority areas were guided by a risk matrix that we developed in consultation with SDC at the outset of the study. The environmental factors that were identified as having the greatest impact were:
- Groundwater levels;
- Annual rainfall;
- Extreme rainfall;
- Alpine and foothill river flows (floods and low flows);
- Evapotranspiration; and
- Sea level rise.
Table 8‑4 outlines the key conclusions that were determined in the study.
Table 8‑4 Key Conclusions
Temperature
| - Average temperatures across New Zealand have increased 1°C over the last 100 years.
- By 2048 temperatures are projected to be 0.8°C warmer (on average) compared with the last 20 years (1995 to 2015).
|
| Evapotranspiration | Evapotranspiration rates are expected to increase by about 3% by 2048. |
| Mean annual rainfall | - There is no long term trend observed in mean annual rainfall on the Canterbury Plains, despite a 1°C increase in temperature.
- Canterbury Plains and foothill rainfall is likely to remain relatively unchanged over the next 30 years.
- Alpine rainfall may increase by over 5% over the next 32 years.
|
| Extreme rainfall | - There is no observed long term trend in extreme rainfall events on the Canterbury Plains, despite a 1°C increase in temperature.
- Based on long term historic trends, we would not expect a statistically significant change in extreme rainfall on the Canterbury Plains over the next 32 years.
- MFE's generic New Zealand wide recommendation of allowing for an 8% increase in extreme rainfall magnitudes per 1°C increase in temperature is not evident in the historic record for the Canterbury Plains.
- The near negligible climate change projections of mean annual rainfall for the Canterbury Plains indicate the changes in extreme rainfall magnitudes are unlikely to be large.
- Current industry design guidelines to allow for an 8 % increase in extreme events per 1 oC warming appear to be conservative for the Canterbury Plains. We recommend further more detailed investigations is required before any changes are made to these guidelines
- Extreme rain events in alpine areas (e.g. Arthurs Pass) could increase by 6-8%.
|
| Other climate variables | - Climate change will have a relatively minor impact on the overall amount of snow in the high mountains of the Southern Alps and snow frequency on the Canterbury Plains.
- Average wind on the Canterbury Plains will remain relatively unchanged, while the number of very windy days could increase by 1 to 2 %.
|
| Groundwater | - We expect climate change will have only a minor impact on groundwater levels over the next 32 years.
- Central Plains Irrigation has a much greater impact than climate change and will increase groundwater levels.
- Record low groundwater levels in 2016 are due to a combination of below average rainfall and increased pumping of groundwater for irrigation.
|
| River flows | - Mean annual flows in the alpine rivers (e.g. Waimakariri and Rakaia) could increase by about 8% by 2048, as a result of increased precipitation.
- Foothill river flows may slightly decrease over the next 32 years, due to a small increase in evapotranspiration.
- We expect climate change will only have a minor impact on flows in lowland streams and drains.
|
| Sea level rise | - Local sea levels have risen 0.19 m over the last 100 years.
- Sea levels could rise by a further 0.08 to 0.23 m by 2048
- Sea level rise will result in either the Te Waihora/Lake Ellesmere mouth needing to be opened more frequently and/or an increase in lake levels. Without any change in lake management lake levels would rise by 0.08 m to 0.23 m by 2048. This change is 10%- 30% of the Lake's normal operating range.
- Sea level rise may result in a minor increase in flooding frequency at Rakaia Huts.
- Sea level rise could have a minor impact on groundwater levels at the coast. Impacts quickly diminish and are very small beyond about 1 km inland.
|
8.3.2 Climate Change Implications for the Activity Areas
The risk matrix developed by Aqualinc Research Ltd in conjunction with Council is outlined in Table 8‑5 below. Whether or not an asset is affected depends both on the assets sensitivity to change and the scale of change. These asset sensitivities were combined with predicted changes to give the expected impacts of Climate Change on assets.
Table 8‑5 Asset Vulnerability
Groundwater levels (upper plains)
| High
| Minor
| Minor
| Minor
| Minor
|
| Groundwater (lower plains) | Low | High | High
| High | Low |
| Annual rainfall | Moderate | Minor | Minor | Minor | Moderate |
| Extreme rainfall (plains) | Moderate | High | High | High | Moderate |
| Extreme rainfall (foothills and alpine) | High | High | High | High | Moderate |
| Alpine river flows | Moderate | Minor | Minor | Minor | High |
| Foothills and lowland river flows | Moderate | Minor | Minor | Minor | High |
| Evapotranspiration (ET) | High | Minor | Minor | Minor | Minor |
| Sea level rise <0.23m | Minor | Low | Low | High | Minor |
| Snow and ice (excl. alpine river flows impacts) | Minor | Minor | Minor | Minor | Low positive |
| Temperature (excl. ET impacts) | Minor | Minor | Minor | Minor | Minor |
| Wind (excluding ET impacts) | Moderate | Moderate | Minor | Minor | Minor |
Table 8‑6 outlines the predicted climate change for each of the 5Waters and Table 8‑7 outlines the impact of this on the infrastructure assets.
Table 8‑6 Predicted Climate Change
| Groundwater levels (upper plains) | Minor
| Minor | Minor
| Minor
| Minor
|
| Groundwater (lower plains) | Minor | Minor | Minor | Minor | Minor |
| Annual rainfall | Minor | Minor | Minor | Minor | Minor |
| Extreme rainfall (plains) | Minor | Minor | Minor | Minor | Minor |
| Extreme rainfall (foothills and alpine) | Moderate | Moderate | Moderate | Moderate | Low |
| Alpine river flows | Small Increase | Small increase
| Small increase | Small increase | Small increase |
| Foothills and lowland river flows | Low | Minor | Minor | Minor
| Small decrease |
| Evapotranspiration (ET) | 3% Increase | 3% increase | 3% increase | 3% increase | 3% increase |
| Sea level rise <0.23m | 0.05-0.23m increase | 0.08-0.23m | 0.08-0.23m increase | 0.08-0.23m increase | 0.08-0.23m increase |
| Snow and ice (excl. alpine river flows impacts) | Minor | Minor | Minor | Minor | Minor |
| Temperature (excl. ET impacts) | 0.8 C increase | 0.8 C increase | 0.8 C increase | 0.8 C increase | 0.8 C increase |
| Wind (excluding ET impacts) | Low | Low | Minor | | Minor |
Table 8‑7 Asset Impact
| Groundwater levels (upper plains) | Minor | Minor
| Minor | Minor
| Minor |
Groundwater (lower plains)
| Minor
| Minor | Minor | Minor | Minor |
| Annual rainfall | Minor | Minor | Minor | Minor | Minor |
| Extreme rainfall (plains) | Minor | Minor | Minor | Minor | Minor |
| Extreme rainfall (foothills and alpine) | Moderate negative | Moderate negative | Moderate | Moderate | Low |
| Alpine river flows | Minor positive | Minor | Minor | Minor | Small positive |
| Foothills and lowland river flows | Low negative | Minor | Minor | Minor | Low |
| Evapotranspiration (ET) | Low negative | Minor | Minor | Minor | Minor |
| Sea level rise <0.23m | Minor | Low negative | Low | Moderate to high | Minor |
| Snow and ice (excl. alpine river flows impacts) | Minor
| Minor | Minor | Minor | Minor
|
| Temperature (excl. ET impacts) | Minor | Minor | Minor | Minor | Minor
|
| Wind (excluding ET impacts) | Low negative | Low negative | Minor | Minor | Minor |
Overall climate change impacts for each of the 5Waters activities are listed below.
Water Supplies
-
Climate change will probably have only a minor impact on most aspects of SDC potable assets over the next 32 years.
-
Higher evapotranspiration may mean 1-2% higher peak water demands.
-
Higher alpine flood flows may have some impact on Arthurs Pass, Castle Hill and Lake Coleridge water supply intakes.
Wastewater
-
Climate change will probably have only a minor impact on most aspects of SDC wastewater assets over the next 32 years.
-
Higher alpine rainfall and flood flows may result in an increase in stormwater inflows for the Arthurs Pass, Castle Hill and Lake Coleridge wastewater systems.
-
An increase in sea level of up to 0.23 m may have an impact on Upper Selwyn Huts, Rakaia Huts and Lakeside wastewater systems.
Stormwater
-
Climate change will probably have only a minor impact on most aspects of SDC stormwater assets over the next 32 years.
-
Higher alpine rainfall and flood flows may result in an increased occurrence of surface flooding at Arthurs Pass, Castle Hill and Lake Coleridge.
-
An increase in sea level of up to 0.23 m may have a minor impact on stormwater drainage systems at Rakaia Huts.
Land Drainage
-
An increase in sea level of up to 0.23 m may impact on Lake Ellesmere/Te Waihora levels and parts of the land drainage network.
-
A projected 6-8% increase in flood flows may impact on Arthurs Pass Bealey River flood protection systems.
-
Other aspects of climate change will probably have only a minor impact on land drainage systems over the next 32 years.
Water Races
-
Climate change will probably have only a minor impact on most aspects of the SDC water race system.
-
An increase in alpine flood flows could result in a small increase in flood damage to intakes. Conversely higher alpine flows would improve reliability of supply.
-
A potential minor reduction in flows in the Kowai River might have a small impact on reliability.
8.3.3 Response to Climate Change Implications for Water Supply
Environment Canterbury is responsible for the management and allocation of water resources in the district. As a major stakeholder in this resource, Council will need to work closely with Environment Canterbury to protect the water resource necessary to sustain district communities now and in the future. Proposed actions include:
- Work with ECan to improve management/allocation of the groundwater resource to halt/reverse declining groundwater levels for community and domestic purposes;
- Work with ECan to better understand the groundwater resource and promote efficient use of water in the district;
- Inform ECan of the potential implications on essential services and work with ECan to develop management strategies and contingency plans to ensure that these services can be maintained; and
- Assess reasonable water supply needs for current and future district communities and lobby ECan to implement policies and rules to protect sufficient water resources for the current and future needs of district residents.
These actions have been carried out where relevant, for example written submissions to Environment Canterbury regarding the LWRP. Council staff will continue to monitor Environment Canterbury's plans and policies.
8.4 Energy
The 5Waters activity is energy intensive, accounting for approximately half of Council's total electricity consumption. The major power demands are from water and wastewater pumping stations and treatment facilities. The direct use of fossil fuels is generally limited to emergency power generation equipment, but the indirect use of transportation fuels for operation and maintenance activities should also be considered when planning changes to energy management. Energy, in varying forms, is used during the construction and renewal of assets and the manufacture of materials used in construction, operation and maintenance of assets.
Carbon emissions for many current energy sources contribute to climate change. Figure 8‑1 below shows the electrical energy costs forecasted during the LTP period as well as the past three years (one budget and two actual).
Figure 8‑1 Electrical Energy Forecast
Energy prices have increased significantly over recent years, impacting on operational costs for the 5Waters activity. This trend is expected to continue.
Council's 5Waters Strategy has identified that:
- Council will monitor current and forecast fossil fuels prices and associated effects on its asset management and operation annually. It will identify effective and efficient opportunities to reduce usage and reliance on this energy source, and seek reliable and sustainable alternatives as they arise;
- Council will minimise the use of and conserve energy, as far as practicable while still meeting agreed levels of service. This will extend to all private services in time where a need is recognised; and
- Council will undertake to identify and reduce carbon emissions where a benefit is shown, through more efficient use of materials and services.
It is necessary to consider energy issues in relation to the 5Waters activity to ensure the sustainability of this activity and achieve/maintain the agreed levels of service. Key level of service linkages are presented below in Table 8‑8.
Table 8‑8 Key Level of Service linkages
| The Community is provided with water services to a standard that protects their health and property | The treatment of water and wastewater can be energy intensive and may lead to increased carbon emissions. |
| Customers are provided with and fairly charge for water services that meet their reasonable needs | If greater per capita demand is placed on water services, then energy costs and carbon emissions may rise. |
| Nuisance effects of water services are minimised | Indirect effects of increased energy use. |
| Water services are provided in a cost effective manner | Reducing / minimising energy demand will reduce exposure to increasing energy prices, improving cost efficiency. |
| Problems with water services are addressed in a timely manner and prioritised according to risk and need | Reliability of energy supply – loss of power or low fuel supplies may result in loss of service capability. |
| Service capacity is provided to accommodate growing communities, where this growth is sustainable | As communities grow, the energy requirements for water services will also grow. |
| Adverse effects of water services on cultural and heritage values are minimised | Increased energy use, in particular fossil fuels, can affect air quality |
| Adverse effects of water services on the environment are minimised | Reducing energy demand, and in particular fossil fuel demand will reduce environmental impacts from that energy production and use. |
| Greenhouse gas emissions from the provision of water services are minimised | Reduced use of fossil fuels and energy derived from fossil fuels, including energy embedded in construction materials and other consumables will reduce greenhouse gas emissions. |
8.4.1 Electrical Energy Supply Contract
Electrical energy is supplied to approximately 240 sites, with range of infrastructure at each site including street lighting, water, wastewater and land drainage assets.
Selwyn District Council procures electricity directly from Meridian, and has an overarching supply agreement.
Electricity bills are received from Meridian but Council is currently unable to measure the number of kW used electronically. A solution to this would be to obtain electronic billing information from Meridian, allowing Council staff to monitor electrical energy usage (and costs) within the AMS. A platform will need to be built in AMS, this is listed an as improvement action for commencement in 2020/21.
8.4.2 Alternative Energy Sources
In 2008, some preliminary work was undertaken to identify and evaluate alternative energy sources. This initially focussed on the potential to use solar panels and wind turbines to power low demand sites, e.g. telemetry installations. Capital costs far outweigh the very low annual energy cost savings making conversion of existing sites unattractive. Solar panels may be a viable option for new installations without an existing mains power supply.
Small solar/wind energy systems are not suitable for higher power demand sites such as UV water treatment plants and water/wastewater pumping stations. As part of the risk assessment process for Darfield deep well siting (2010-2011), water race use for generation of power was considered.
8.4.3 On-Site Power Generation
Council own a number of diesel powered generators installed at key water and wastewater sites as standby emergency power supplies. There is potential to utilise these systems during peak power demand periods and take advantage of lower tariff structures.
Another option under consideration is to use the generation capacity to supply the main grid at peak times when the electricity spot price is high.
These options may provide net cost savings for Council, but need to be considered in a wider context for alignment with the Sustainability Principles. Any use of diesel generation capacity consumes non-renewal fossil fuels contributing to greenhouse gas emissions. A significant capital investment would be required to modify the existing equipment to supply power to the grid, and supply contracts would need to be negotiated that did not compromise the ability to use the generation capacity for the purpose for which it was originally intended.
8.5 Improvement Planning
Throughout this section a number of specific actions to improve the way in which the Council identifies and manages infrastructure sustainability associated with the 5Waters activity have been identified. These actions are summarised below in Table 8‑9.
Table 8‑9 AM Improvement Items – Infrastructure Sustainability
8.2.1
| Reasonable Use Model
| Medium
| 2018/19
|
| 8.2.3 | Monitor developers/developments to ensure sustainable infrastructure is provided in the district | Medium | Ongoing |
| 8.2.4 | Consolidate rates to ensure financial sustainability (recognised more appropriately as an improvement item in Section 11) | High | Ongoing |
| 8.2.4 | Integrate schemes where economically viable (recognised more appropriately as an improvement item in Section 11) | Medium | Ongoing |
| 8.3.3 | Extend the Climate Change study to 120 years to be in line with the lives of infrastructure assets | Low | 2019/20 |
| 8.4 | Monitor electrical energy usage within AMS | Medium | 2021/22
|
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