CCP-NZ 2009 report
The latest CCP-NZ report has a wealth of information about factors influencing climate change in NZ. Click here for the report, which is on the CCP-NZ website.
The following is an extract, covering water and wastewater (I have emphasised some parts).
Water and sewage
The water supply and sewage (waste-water) pumping and treatment sector is responsible for more than 25 per cent of corporate emissions from CCP-NZ councils. This highlights this sector as one where savings should be sought. Studies and pilot programmes around the world have documented the potential for large savings of emissions through reduced water consumption and by not treating all water to drinking-water quality if not required. Significant challenges need to be addressed to implement such behavioural and infrastructure changes.
Councils report that public water conservation promotional campaigns are usually only effective for short-period supply restrictions such as summer droughts. Such campaigns do not provide reliable longer-term efficiencies that reduce the need for new water supply infrastructure (e.g. dams and treatment systems). Behavioural change needs to be supplemented by technology-supported improvements.
ICLEI Oceania facilitated Milestone 3 workshops for council staff developing local action plans. Staff identified four solutions with significant potential for energy and emission reductions for this sector:
- Optimising pumping technology and controls, such as installing variable-speed drive pumps to work alongside fixed-speed drive pumps – often results in more efficient water supply and sewage systems
- Installing water meters on customers’ supply points – demonstrated to reduce domestic water use and wastage
- Installing rainwater and greywater collection facilities for new buildings or subdivisions – attractive for councils with water supply problems, and rainwater tanks smooth the flow impacts from stormwater systems during high-rainfall events
- Analysing electricity tariffs for water and sewage pumping – significant cost savings.
CCP-NZ councils’ actions to reduce emissions from the water and sewage sector are resulting in more than 1,700 tonnes CO2-e being saved annually. Beacon Pathway studied water supply energy and emissions issues, using input from four CCP-NZ councils. Its findings will be published later in 2009.
Water and sewage
The water supply and sewage
(waste-water) pumping and
treatment sector is responsible for
more than 25 per cent of corporate
emissions from CCP-NZ councils.
This highlights this sector as one
where savings should be sought.
Studies and pilot programmes
around the world have documented
the potential for large savings of
emissions through reduced water
consumption and by not treating all
water to drinking-water quality if
not required. Significant challenges
need to be addressed to implement
such behavioural and infrastructure
changes.
Councils report that public waterconservation
promotional
campaigns are usually only effective
for short-period supply restrictions
such as summer droughts. Such
campaigns do not provide reliable
longer-term efficiencies that reduce
the need for new water supply
infrastructure (e.g. dams and
treatment systems). Behavioural
change needs to be supplemented
by technology-supported
improvements.
ICLEI Oceania facilitated
Milestone 3 workshops for council
staff developing local action plans.
Staff identified four solutions with
significant potential for energy and
emission reductions for this sector.
• Optimising pumping technology
and controls, such as installing
variable-speed drive pumps to
work alongside fixed-speed drive
pumps – often results in more
efficient water supply and
sewage systems.
• Installing water meters on
customers’ supply points –
demonstrated to reduce
domestic water use and
wastage.
• Installing rainwater and
greywater collection facilities for
new buildings or subdivisions –
attractive for councils with water
supply problems, and rainwater
tanks smooth the flow impacts
from stormwater systems during
high-rainfall events.
• Analysing electricity tariffs for
water and sewage pumping –
significant cost savings.
CCP-NZ councils’ actions to reduce
emissions from the water and
sewage sector are resulting in more
than 1,700 tonnes CO2-e being
saved annually.
Beacon Pathway studied water
supply energy and emissions issues,
using input from four CCP-NZ
councils. Its findings will be
published later in 2009.
Add comment August 17, 2009
UK report on rainwater and greywater reuse
This is a largely sensible report, following on from the DEFRA report, but note that it only considered greywater use from the bathroom for toilet flushing. In NZ there is a system of similar cost that can also take washing machine water and irrigate the garden (as well).
Add comment July 1, 2009
The UK Government’s water strategy
The report by DEFRA (the Department for the Environment, Food and Rural Affairs) has the following in the foreword:
The problem we face is this; because of our need to adapt to climate change, our water intensive lifestyle and other pressures such as changing land use, we need to find ways of using water much more efficiently and sustainably if we are to continue to enjoy high standards and constant supply.
The South East and East of England already face increasing demand on a finite water supply. The drought of 2004-06 was only managed through controls on what we could use water for. This was not a one-off; indeed droughts are likely to be more common. By 2080, some long term climate projections forecast half as much rainfall in summer (nothing like fully offset by 30% more rainfall in winter) in the South East.
We need to plan ahead and each of us needs to play our part. We have, of course, not only to cope with too little water. Indeed the last year has been characterised more by too much water with serious flooding in many parts of the country. Sir Michael Pitt’s report into these floods shows that we still have lessons to learn as a country about defending ourselves from, and learning to live with, floods. One particular issue is how we cope with ‘surface water’ flooding. Just as climate change seems likely to mean less water on average, it is also likely to mean more extreme weather events, with more inland and coastal flooding.
Finally, the way we pump, treat, clean and heat water has profound implications for energy use. The water industry is a major energy user, and together with domestic hot water use, there’s a carbon impact here that simply has to be tackled. Saving water reduces emissions.
1 comment July 1, 2009
Water Footprint of Bioenergy
The water footprint of bioenergy is large compared with other forms of energy, with one litre of biofuel costing between 1,400 and 20,000 litres of water, according to a journal paper.
2 comments June 30, 2009
Victoria’s Water Policy ’shambolic’
An article in The Age newspaper says that the Australian State of Victoria is locked into a billion dollar water pipeline which can’t deliver much if any water without causing major downstream problems to the Murray river and may not be able to build its desalination plant due to the failure of Suez and Veolia to secure funding. Meanwhile rainwater, greywater and other practical recycling schemes are ‘being closed off’.
Add comment June 30, 2009
Gisborne Considers Recycling Wastewater
Summary
Currently it is estimated to cost $2 per cubic metre, compared to potable water at $0.80. The cost of recycling may decrease with new technology and the cost of producing potable water will increase with higher standards. Thus the potential to recycle water from the new wastewater treatment system in Gisborne is being investigated under a consent for ‘alternative use and disposal’.
Add comment June 26, 2009
Kapiti Coast Plan Change 75
The following is the Kapiti Coast District Council’s press release, dated 18 June 2009. For more info, see the KCDC website. I believe that the plan change is a very positive step in the right direction, despite it not making provision for greywater recycling to the home as a permitted activity (for more information see my earlier submission on the plan change posted on this site).
A single greywater system recycling water for toilet flushing and garden watering will be permitted as an alternative solution under the plan change and despite the small additional application cost it will be by far the cheapest and most efficient way to comply with the requirement of the plan for all new houses to save water. Other ways to comply include a mixture of rainwater tanks and greywater for garden irrigation only or a very large rainwater tank only. All of these methods are good ways to save water.
KCDC press release:
Tanks & greywater for new Kapiti Coast homes
Council confirms tanks and greywater plan
Kapiti Coast District Council today approved a district plan change making it compulsory for all new homes to have an alternative non-potable water supply for outdoor uses and for washing machines and toilet use.
Mayor Jenny Rowan hailed this as a major step in the long term programme to manage water use and supply in the district and said it sent a very clear signal that the Council is serious about conserving and managing the use of its potable treated (drinking) water supplies.
“As much as 40% of the water used during the summer months is for outdoor uses,” she said.
Plan Change 75 requires all new dwellings in the district to have either a 10,000 litre rain water storage tank or a combination of a smaller 4000 litre rainwater storage tank and a greywater irrigation system. There is also provision for consideration of other water solutions which provide a non-potable water source for outdoor use.
The plan change builds on an existing policy in place since 2002 where water use in newly rezoned subdivisions has been controlled through a requirement for water saving devices and restricting the supply to 1000 litres per household per day.
“This is all part of our long term programme which recognises the need to reduce demand for water arising because of new development and to develop conservation packages,” Mayor Rowan said.
“Water quality and supply is clearly the number one concern in our District.
“We’ve set aside money in our long term plan for improving supply/storage capacity, and for a comprehensive conservation package, including public education and the investigation of a range of incentives for initiatives such as the installation of water conservation systems for consideration during next year’s Annual Plan process.”
“We know rainwater storage tanks reduce outdoor water use and, combined with greywater irrigation systems which apply waste water from washing machines and bathrooms through in-ground irrigation systems, there is the potential over time to reduce use of potable water for outdoor uses considerably, and extending the life of our supply systems,” she said.
1 comment June 25, 2009
Water System Failures – Amenable Ergonomics Study? (note to self)
At some point I’d like to conduct an Ergonomics/Human Factors investigation of failures in complex water systems. Here are a couple of examples:
- Up to three safeguard systems are reported to have failed at the Brisbane water-treatment plant that released drinking water to residents with FLUORIDE levels that were 20 times the legal limit. SEQ Water Grid Manager Director confirmed the water entered supplies in the Brendale and Warner areas on May 2 for three hours. (The Australian) (News.com)
- Another incident was caused when production water from a uranium mining process was cross-connected to the drinking water supply in the processing plant, allowing process water containing uranium and other contaminants to enter the drinking water supply. Workers at the mine were exposed through drinking and showering in the contaminated water, and some water also entered the drinking water supply to the nearby town of Jabiru East. (Health Stream)
There are many more examples including literally thousands of cross-connection incidents annually, but these examples have a certain complexity that requires a systems approach to their investigation and ‘human error’ would be a significant factor.
Note to those not familiar with ergonomics/human factors: the actual errors that resulted in the incident would likely have been preceeded by latent, or design, errors which made the active failure more likely. By using a human factors approach to their study it should be possible to develop systems to identify if these design issues are present elsewhere and to help avoid them in the future. Staff re-training and technological back-ups are not likely to help and the latter may introduce more problems than it solves, due to greater complexity.
More on Ergonomics/Human Factors: International Ergonomics Association
Please comment on this article if you have any references to ergonomics/human factors investigations of water systems, or further examples of complex system failures.
4 comments May 19, 2009
Submission to Auckland City Council’s LTCCP 2009-2019
Section: “Advocacy: utilities advocacy” (and/or elsewhere as appropriate)
I submit that the LTCCP should introduce a key project to fully investigate the costs, benefits, risks and legal status of greywater recycling. Another project should fully investigate the same factors for rainwater tanks. Part of these studies should consider reducing the barriers to implementation of these systems, if deemed appropriate. For example, setting a building consent cost of $0 (zero) as per solar hot water systems.
I note that some work has recently been completed by EUM and Metrowater on these topics, but I believe the work to be seriously deficient, with incorrect findings. Certainly the findings run contrary to those of the Kapiti Coast District Council which has commissioned more extensive research and is moving to mandate the use of greywater recycling systems and rainwater tanks.
Regarding the deficiencies of the research into greywater, there is an extraordinary cost-benefit analysis which allows for a 25% reduction in water usage, whereas Metrowater’s figures show a 50% reduction would be the average; which allows for interest on capital costs at 12.5%, which is substantially higher than the typical mortgage cost which would be a reasonable rate to use, and higher still than the 5% discount rate which is often applied; and which makes no allowance for the planned increases in water costs, holding them constant despite evidence that costs can be expected to double over the next decade – there’s not even an allowance for inflation. I have conducted a comprehensive cost-benefit analysis which does not suffer from these methodological errors and which accordingly finds greywater recycling to be an outstandingly good investment in Auckland City, giving an internal rate of return of 17.86% (this is comparable with an alternative investment, such as a bank deposit), saving a typical family in the region of $328.40 per annum on their water bill. I have attached in Appendix 1 my paper to the NZ Land Treatment Collective conference in which these calculations appear (refer also to my NZ Waters and Wastes Association paper for further details on the methodology if required – referenced in the NZLTC paper and available on my www.watermiles.org website).
Further deficiencies in the EUM/Metrowater discussion document centre on mis-calculation or misunderstanding of the level of risk involved. Work done by Yarra Valley Water (Melbourne, Australia) for instance has found that on-site systems have a lower level of risk than centralised infrastructure, due to the lower numbers of people having contact with the water both before and after recycling. This is written up in Francis Pamminger’s case study in Appendix 2. In general it is my opinion that an on-site greywater system which is used for toilet flushing and garden watering has an equal or lower risk than a spa pool. The processes involved are broadly similar, but with a spa pool there is a much higher level of contact with the ‘recycled’ water. There is also a lower maintenance requirement for the greywater system.
In discussions I’ve had with people responsible for the discussion document within council and at Metrowater, some alarming figures (such as on-site systems costing seven times as much as centralised systems) have been quoted to me. All the research I have seen has found on-site systems to be as cheap or cheaper. For example there has been cost-benefit analysis work done by Landcare Research into rainwater tanks, plus my own research on greywater and Francis Pamminger’s work on on-site systems vs centralised infrastructure generally. None of this research was apparently known to the authors of the discussion document, calling into question its validity and utility.
Additionally, there is a potential conflict of interest associated with having Metrowater involved in developing such policy. Advocating on-site rainwater and greywater systems would be advocating a reduction in Metrowater’s profits as it could not charge for this water. As such it is necessary that an independent researcher or research organization is employed to consider these issues. I offer to assist in the study proposal and/or design and/or consideration of tenders and suggest that external assistance is badly needed to enable Auckland City to develop a serious policy on rainwater and greywater recycling. It should be noted that the potential benefits are massive in terms of financial savings, reduced need for infrastructure and reduced greenhouse gas emissions.
CCP-NZ
Auckland City should make reference in the LTCCP to its aim to progress through the CCP-NZ milestones and attach dates to aim for to achieve each milestone. Note: greywater recycling and rainwater harvesting can help achieve these milestones by reducing greenhouse gas emissions compared with centralised infrastructure for water provision.
Add comment May 18, 2009
Submission to Proposed Regional Policy Statement – Wellington Region
I made this submission to Wellington’s RPS. Submissions are open to 8 June. It’s a well laid-out document, so easy to submit on.
Policy 18 – Support and Amend
Insert c) promote the recycling of water, especially on-site; Insert d) promote the capture of rainwater on-site; Insert into Explanation: The capture of rainwater on-site reduces demand for centralised infrastructure for water provision. The recycling of water on-site reduces demand for centralised infrastructure for water provision and for wastewater treatment. On-site water systems usually have lower life cycle costs (both financial and environmental) than centralised water systems, comparable or reduced risks and greater resilience.
Policy 44 – Support and Amend
Comment: reuse of rainwater and greywater for flushing toilets is ‘safe’ when done at the domestic (single household) level. The use of recycled water becomes ‘unsafe’ when it is done on a wide scale where many different households may contact the water both before and after recycling. I submit my paper to the recent NZ Land Treatment Collective conference on Recycled Water as supporting evidence (see link). I understand that the Ministry of Health has a very conservative view of greywater recycling, but it is slowly changing its view, eg it now appears to ‘support’ greywater reuse for garden irrigation where previously it did not. It certainly now ‘supports’ rainwater reuse where previously it was opposed. I expect that in time it will ‘support’ greywater reuse for toilet flushing in a single domestic dwelling. It appears to offer conditional ‘support’ water recycling on a larger scale – presumably because it traditionally feels more comfortable with centralised infrastructure and does not fully appreciate that the existing risks from this infrastructure often exceed the risks from ‘novel’ decentralised approaches, nor has it so far fully appreciated the relative risks associated with the higher financial and environmental costs of centralised infrastructure and the climate change (and other) benefits of decentralised systems. These are increasingly being researched and becoming understood. I submit a paper by Francis Pamminger of Yarra Valley Water (Melbourne, Australia) which illustrates this nicely (see link). In conclusion, I understand that there are complex and diverse influences on the precise nature of this policy and its wording and I commend the careful wording of the policy, which is appropriate given the developing understanding in this area.
Proposed amendment: I would like to see it state that the reuse of non-kitchen greywater sources is safe for toilet flushing in a single domestic dwelling but I understand that this may have to wait for next time.
Comment: The current wording that ‘recycled water…can be used for toilet flushing’ must remain as a bare minimum to allow this practice to continue to occur (as is permitted by the Building Act/Code).
Proposed amendment: I would suggest adding and greywater to the above wording for clarity.
Policy 65 – Support and Amend
Insert: Greywater recycling reduces water use and wastewater production, which in turn reduces energy use (water services being a major consumer of energy). Greywater recycling systems should be encouraged in individual households by the provision of information and advice. A reduced (preferably zero) fee should be charged for building consent applications for greywater recycling systems to recognize this benefit, which is directly comparable to the policy adopted for solar hot water systems.
A similar policy for rainwater tanks should be considered where consent application fees apply.
Method 11 – Support and Amend
Modify: “Prepare and disseminate information about water conservation, greywater recycling, rainwater harvesting and the efficient use of water”
Method 33 – Support and Amend
Insert: d) greywater reuse and rainwater harvesting. Comment: I should like to be consulted during the development of these strategies.
Method 55 – Support and Amend
Insert: d) recycle water on-site. Comment: on-site water recycling reduces energy use as well as water use and wastewater production.
Add comment May 15, 2009
