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Appendices

Appendix 1 Examples of ecosystem goods and services

Table A1

Appendix 2 Legislation relevant to wastewater management

The Resource Management Act 1991 (RMA)

The RMA controls most of the consents your community will need. The purpose of the Act is to promote the sustainable management of natural and physical resources. It provides for the preparation of regional policy statements, policies and plans, and the preparation of district plans. The control of specific activities is achieved through the rules in these plans and through resource consents.

The RMA does not explicitly provide for the management of waste: it provides for the management of environmental effects, including those arising from the disposal of waste as part of a wider focus on the effects of actions on the environment. The Act requires that adverse effects are avoided, mitigated or remedied.

The RMA is an enabling piece of legislation that provides councils with considerable discretion and opportunity in its interpretation.

The Hazardous Substances and New Organisms Act 1996 (HSNO)

This Act provides for the protection of the environment by preventing or managing risks to the environment from hazardous substances and new organisms.

The HSNO legislation takes a life-cycle approach to the management of hazardous substances, including their disposal, when such substances are no longer wanted and become waste. The disposal of waste hazardous substances is controlled through the Hazardous Substances (Disposal) Regulations 2001. These regulations provide for the treatment of the different classes of waste hazardous substances before disposal so that the substances are no longer hazardous.

The Health Act 1956

This requires territorial authorities to ensure waste is collected and disposed of, promote and protect public health, and report diseases and unsanitary conditions to the medical officer of health. The local authority must 'secure the abatement' of any nuisance likely to injure or be offensive to health.

The Local Government Act 2002

The Local Government Act 1974 was reviewed in 2002. The new Act requires local authorities to take a sustainable development approach. Section 125 requires a territorial authority to assess the provision of wastewater services within its district from time to time. An assessment may be included in the territorial authority's long-term council community plan, but if it is not, the territorial authority must adopt the assessment using the special consultative procedure.

The Local Government Act 2002 contains provisions relating to tradewastes, stormwater, sewage and waste management planning. Tradewastes are generally managed through bylaws. Traditionally the control on tradewastes was to prevent the wastes from harming the sewerage or wastewater network, but increasingly bylaws are being used to control the nature and concentrations of substances in order to manage the type of treatment and final discharge of wastes.

Key themes in the Act which impact wastewater management are summarised below.

  • Sustainable communities: the overall purpose of local authorities is to promote the community's social, economic, environmental and cultural wellbeing. These four factors have to considered in every significant wastewater decision a council makes. (This handbook has focused on all four factors.)
  • Long-term planning: councils must determine their community's long-term outcomes and priorities in an integrated way, and this process must include provision for public submissions. In addition, each council must prepare a 'long-term council community plan' which shows what the local authority intends to do towards achieving the desired outcomes.
  • Consultation: in determining community outcomes and priorities, in planning and when making significant decisions, local authorities must engage in public consultation.

In addition to these general themes there are specific new provisions in the Act relating to the management of wastewater.

  • Part 7 of the Act requires local authorities to make "an assessment" of water services from time to time. This requires an exhaustive examination of the water, sewerage and stormwater functions, including present arrangements, future demand, delivery options and conservation strategies. The assessment is subject to a public consultation process and it (or a summary of it) must be included in the council's long-term council community plan.
  • Section 130 obliges local authorities to maintain water services.
  • Section 131 allows local authorities to close down small water services – but only after a referendum.
  • Section 136 limits contracts for water services operations to 15 years and in these circumstances it must retain control over pricing, management and the development of policy.

Appendix 3 Wastewater production, water consumption and water-conserving technologies

Wastewater production

Table A1 sets out information on wastewater production based on data from Christchurch. This information would be typical of most communities on a public water supply.

Table A2 The amount of wastewater produced per day

Table A2 shows the amount of phosphorous and nitrogen produced. Both of these have a major impact on the nutrient cycle and need treatment.

Table A3 Phosphorous and nitrogen produced per day

If urine is diverted from the domestic wastewater, and greywater and toilet flushing is reduced by 50% by using more efficient water technologies in each home, the volume of domestic wastewater going to a wastewater treatment plant could be reduced by over 50%. This would also mean nitrogen going to treatment would be reduced by 80%, and phosphorous by 30%.

Water consumption

Water consumption per person varies from town to town and throughout the year. Obviously water consumption will increase considerably in the summer when people water their gardens and lawns.

Waimakariri District Council estimates a peak domestic daily water requirement of 1,000 to 1,500 litres per person. This includes a rather generous allowance for garden and lawn irrigation requirements. For Christchurch City, peak daily per capita water consumption is up to 2,000 litres, while the minimum is 200 litres. The daily average is 450 litres/person. These figures are based on city-wide consumption figures, which will include water consumed by industry and commercial activities.

For a small community in a rural area, industry and commercial uses will usually be quite small. The typical water consumption rate for household activities (excluding uses such as garden irrigation, car washing and swimming pool use) is about 180–200 litres person per day.

Table A4 Comparison of water use between conventional and water-saving domestic appliances

Water-saving technologies

Table A3 is an illustration of possible water savings using water-saving technologies.

Toilets

There are now a number of different toilet designs available in porcelain, stainless steel and plastic. The volume of wastewater coming from the different toilets varies considerably. These systems include:

  • water-saving (usually dual-flush) toilets
  • vacuum toilets
  • composting toilets.

For each of these systems there may be the option of a urine-separating design, or the traditional non-separating design producing blackwater. For those systems with urine separation there is a separate urine-flushing mechanism, which uses considerably less water than the faeces flush.

The older type of single-flush toilets would use up to 15 to 20 litres of water per flush. Many older homes are likely to have these types of toilets. The dual-flush toilets have flushing volumes ranging from full flush to reduced flush volumes of 11 to 5.5 litres, 6 to 3 litres and 3.3 to 1.5 litres.

Vacuum toilets

Vacuum toilets are now used overseas in residential units. Several home units (eg, in an apartment block or cluster homes) may be served by a single vacuum unit. There are also single-toilet vacuum units. The volumes of wastewater from vacuum toilets are very low. Typical daily flush volumes for 1 EDU 22 (representing one average household) using these toilets are given in Table A4. It can be seen from this table that volumes of blackwater can vary considerably with the type of toilet used.

Urine-separating vacuum toilets are being used in some countries in Europe. While it can be seen from Table A4 that this reduces volumes considerably, the other advantage is that it enables the recovery of the nutrients from the urine. Urine is rich in nutrients and typically contains 85% of the nitrogen and 50% of the phosphorus in the total domestic wastewater stream. The other advantage in separating out the urine is that it enables the return of these nutrients back to productive land use. Research carried out on the health risk of separated urine by the Swedish Institute for Infectious Disease Control 23 shows that:

  • E. coli and other coliforms die off quickly in stored urine
  • some micro-organisms such as faecal streptococci and the parasite Cryptosporidium survive longer than E. coli, and probably also some viruses
  • the hygienic risks connected with human urine are a lot less than with faeces
  • the amounts of hormones are very small compared to other sources, and we do not need to worry about them.

Table A5 Typical daily volumes of blackwater per person for different types of toilet

The application of urine separation and recovery technology in Scandinavia has enabled the conversion of urine into fertiliser at central processing facilities. Urine storage tanks associated with apartment blocks enable routine collection of the raw product, which is transferred in bulk to the processing plant. The resulting product is then sold for farm and horticultural use. No such proposals for urine recovery are under development in New Zealand.

Waterless urinals

BRANZ-certified waterless urinals have been installed in a number of men's toilets throughout New Zealand. Each urinal is made from fibreglass-reinforced plastic with a special gel-coat surface. Odour control and hygiene is achieved with a patented alcohol-based sealing fluid with trap.

Composting toilets and greywater systems

See Appendix 4.

Other water-using technologies

Washing machines

Low water-use washing machines can reduce laundry wastewater volumes by 30%. Typically, front-loading washing machines use less water than do top-loading washing machines. The September 1999 Consumer magazine (No. 385) evaluated a number of New Zealand-available washing machines, including a rating for efficiency of water use. Front-loading machines generally rated higher.

Fittings

There are various fittings that can reduce water use in homes and industry. Aerator fittings for shower heads and tap faucets have the effect of increasing the bulk of the aerated water stream, giving a sense of volume but with a reduced real volume of water. This can be effective in showering and hand washing.

Proprietary flow-control valves such as Jemflow and Aqualoc are inexpensive valves that claim to reduce water consumption by up to 35%. These can be fitted into new homes or retro-fitted into existing homes.

In situations where water pressure is higher than necessary, causing excessive flow rates, the fitting of pressure-reducing valves will save water consumption.

Greywater and blackwater separation with specific management

Separating the greywater from the blackwater enables separate management of these two components. There is at least one commercially available system in New Zealand for greywater treatment and recycling: the East Coast (ECO) Wastewater Recycling System (recently certified by BRANZ). Recycled greywater is used for toilet flushing and garden watering.

Conclusions

The key conclusions are as follows.

  • Table A3 shows that internal domestic water use can be reduced by 50% with the adoption of water-saving technologies in the home.
  • Table A4 clearly illustrates that substantial water volume reductions can be achieved according to the type of toilet installed. The organic and nutrient loading of blackwater from an EDU will not be affected by the type of toilet.
  • The greywater component of the domestic wastewater volume can also be reduced by the use of water-saving technologies. Separating the greywater from the blackwater will enable separate and more appropriate management of these two streams. There may also be some situations where greywater recycling would be appropriate. However, on some sites greywater can be managed on-site, and this will reduce the hydraulic loading on centralised sites receiving treated wastewater.
  • For existing homes and enterprises the economic benefits of retro-fitting water-saving (and hence wastewater reduction) technologies would need to be considered carefully. However, it is strongly recommended that new homes and commercial and service units give serious consideration to the installation of water-saving technologies and management techniques. The cost-benefit would need to be evaluated for each specific development.

Appendix 4 Composting toilets

Composting of human waste is an ancient practice. It is only in the last 30 years that systems for modern living have been designed and commercialised for the modern domestic home environment. (Sweden has pioneered these systems). A composting process relies on bacteria and other micro-organisms to break down the organic constituents of human faeces and other organic wastes under aerobic conditions (where oxygen is present).

For human waste to compost well there needs to be the correct moisture content (not too damp) and a balance of carbon and nitrogen components, and it needs to be well aerated. If not, problems may arise, including:

  • odour
  • flies and other nuisance insects.

Figure A1 Typical composting toilet

This figure portrays a typical composting toilet – the Nature-Loo Classic. The toilet comprises a ceramic pedestal with a wooden seat. A waste shoot goes down to a composting chamber underneath the toilet in the under-house area. A hose drains liquids away from underneath the composting chamber, while a flexible air hose leads up to a 100mm vent pipe. This has a fan and a moisture trap and is capped by a vent cap with insect screen and rain hood.

Sound design and good management can overcome a number of these problems. Odour – and to a certain extent excess moisture – can be minimised with good ventilation. Most systems employ an electric fan for forced ventilation. Some systems provide additional heating to accelerate decomposition and moisture evaporation. Excess moisture may be avoided by using urine-separating toilets, although these are not common in New Zealand (see Appendix 3).

Various measures can be taken to minimise the fly problem, such as the use of insect screens and ensuring the compost chamber is sealed against insect access (keep the toilet lid closed when not in use). Other systems use a light trap to attract flies away from the pedestal, which is the most common means of access by flies to the composting chamber. A healthy composting process will attract fewer flies. However, this cannot always be guaranteed.

Management issues include:

  • visual 'uncleanliness'
  • the need for regular and acceptable compost removal and disposal.

Porcelain pedestals are generally easier to keep clean than plastic units. The suppliers of the composting toilet normally advise how toilet bowls should be cleaned.

Care needs to be taken in the handling and disposal of the composted material. After 12 months of well-managed composting it is recommended that the solids be stored for another 12 months before returning to land, preferably by burying in an area where potential human contact is low. If well composted there should be no objectionable smell (maybe an earthy, musty odour) and most pathogens are destroyed, making it safe for handling.

Other management issues related to usage include:

  • the toilet lid should be closed at all times when not in use
  • add no cigarette butts, sanitary towels or nappies, glass, metal, plastic, chemicals or toxic materials.

Composting toilets require on-site management. The obvious advantage of composting toilets is the non-liquidisation (by flush water) of faecal material and the avoidance of problems that liquid waste can cause.

At the same time, any owner wishing to install a composting toilet will need to make provision for the management of greywater. The usual method is to install a reduced-size septic tank in accordance with AS/NZS 1547:2000 followed by a conventional on-site re-entry system such as soakage trenches. Alternative approaches include the use of special grease and sediment traps, followed by a constructed wetland, with the resulting treated effluent being stored for garden irrigation or disposed by sub-soil soakage or dripline irrigation. Where a grease and sediment trap is used instead of a reduced-size septic tank, weekly or monthly maintenance of the trap will be required.

Local authorities have differing attitudes to the use of composting toilets, and you should consult your council to determine their rules related to acceptance and approval of this method of human waste management. It should also be noted that the Ministry of Health does not recommend the use of composting toilets in urban areas.

Appendix 5 New developments and innovations in wastewater servicing

New thinking in treatment technologies is tending to blur the boundary between treatment and re-entry systems. The focus now is on working with ecosystems to beneficially treat environmental pollutants. As with most technologies, new wastewater servicing systems are being researched and developed all the time. This appendix describes some of these developments in New Zealand and overseas. Most are not well proven systems under New Zealand conditions.

Constructed wetland developments

Staged planting wetlands have been used in the US, where up to five wetland units in series are each planted with specific plant species aimed at particular treatment functions, such as organic matter control, nutrient removal and bacterial control.

In septage wetlands the pump-out contents of septic tanks (the septage) is treated by flooding into a shallow basin, within which dense wetland plantings thrive on the nutrients in the solids. As the basin gradually fills at each dose of sludge and liquid, the root systems of the growing plants climb steadily up the older buried stalks. The whole mature sludge/root mass content is eventually excavated and composted, and the basin replanted for continuing use.

Controlled environment aquatics consist of a series of tank cells housed within a 'glasshouse' or other covered and sheltered environment. Treatment is carried out with a series of tanks containing floating plants interspersed with sub-surface flow cells. Some systems include fish tanks. Patented systems include Solar Aquatics, Living Machine and Biological Aquatics. These systems are not currently available in New Zealand.

Oxidation pond developments

The advanced integrated wastewater pond system (AIWPS) has been used in the US since the 1960s, although only to a limited extent. It is now being trialled in New Zealand. It is a five-stage pond system with a deep anaerobic and facultative first stage, followed by a high-rate algal race-track channel, a five-day settling pond, a deep-polishing pond for bacterial removal, and a final storage and maturation pond. The total through-flow time of 24 days compares with the 60 days for a traditional facultative/polishing pond combination, thus reducing the land area required. However, significant hands-on operational supervision is required to ensure the system performs to its optimum.

Reclaimed water developments

Reclamation of water from recirculating sand-filter systems via UV disinfection to enable recycling back onto properties for toilet flushing and closed-cycle garden irrigation is common in the US. A large Australian scheme known as the Rouse Hill project, to the west of Sydney, has been introduced to conserve the use of potable water in the face of restrictions on natural water availability. There were some initial issues resulting from confusion of the two separate water supplies that have subsequently been dealt with by colour coding the greywater supply lilac and utilising left hand threads on the reticulation.

Such technology is recognised to be a public health risk due to the difficulties encountered with differentiation of these non-potable water supplies from the potable supply. It is unlikely to have a widespread appeal in New Zealand until this issue has been resolved. It has been installed for two new 35 and 37 lot subdivisions, one in the Kumeu area north of Auckland, the other in Coromandel on the coast west of Whitianga (see the case study in Section 9.4). The Kumeu project enabled a reduction in the communal land area requirement for final effluent irrigation. The project in Coromandel was required under subdivisional consent to address the issue of water supply availability during the peak summer holiday period.

Ultrafiltration processes utilising membrane filters from the food industry are being trialled in conjunction with disinfection systems to reclaim water for discharge to sensitive environments, and for household re-use applications in Australia. This technology is available in New Zealand.

Greywater recycling for toilet flushing can be provided for individual households in a community situation via a three-stage treatment system that strains, then deodorises, then disinfects household bathroom and laundry wash waters. The resulting product is cloudy in appearance, but entirely suitable for recycling for toilet flushing. It is a New Zealand development, and is applicable for urban households where a saving on both water use and wastewater production is desired by homeowners. It can also be used for existing rural–residential cluster dwellings where reduction in communal land treatment area is desired.

Drip-line irrigation developments

Septic effluent drip irrigation is under trial in the US and in some areas of New Zealand. The septic tank effluent has to be highly filtered by an automatic filter system, with backwash cycling prior to drip-line application. The objective is to provide more effective distribution of primary effluent into aerobic topsoil layers to take advantage of the soil's treatment capacity.

Controlled-drip sub-surface drip-line systems provide a geotextile wick above a plastic strip to ensure that effluent disperses fully along the length of the drip line instead of concentrating at the drip emitters. The objective is to better use the soil system to treat and absorb effluent. This system has been developed in Australia and is available in New Zealand.

Innovations in integrated water wastewater services

There are a range of innovations under trial and investigation overseas as demonstration projects. Some of these are summarised in the box below.

Innovations in integrated water and wastewater services

  • A 3.5 ha development with 350 residents at Flintenbreite, Lübeck, Germany, uses vacuum toilets and sewers, decentralised greywater treatment using constructed wetlands, biogas from blackwater and rainwater retention and infiltration in swales (Otterpohl, 2000).
  • At the Agricultural University of Norway, in Ås, a student apartment building with 24 flats, 54 students and 26 vacuum toilets has been designed to separate the greywater and the blackwater streams. The blackwater is treated and spread on farmland and the greywater is treated on-site by constructed wetlands before disposal to stormwater drains (Etnier et al., 1999).
  • Constructed surface-flow wetland designed to reduce the TN content of the treated wastewater from Oxel sund township (population = 15,000) by 50%. The pre-treatment is mechanical/chemical treatment. There are 22 ha of ponds. Each pond is about 20,000 m3. The water level variation is about 50 to 100 m3. The system manages to provide denitrification and nitrification (Etnier, 1997).
  • Figtree Place, Newcastle, Australia. This project involved 27 residents on 0.6 ha. It includes rainwater harvesting, stormwater soak-aways for groundwater recharge and water technologies achieving 60% saving (Kuczera et al., 2001).
  • Craggs et al. (2001) describe an advanced pond system using high-rate algae ponds for nutrient stripping and harvesting for composting.
  • Wild et al. (2001) describe wetlands planted with Typha (raupo) for wastewater renovation and production of insulation fibre, as carried out in Donaumoos, Germany (6.2 ha wetland).

References for: Innovations in integrated water and wastewater services

Craggs, R.J.; Tanner, C.C.; Sukias, J.P.S.; Davies-Colley, R.J. Dairy farm wastewater treatment by an advanced pond system (APS), pp. 105–111.

Etnier C. and B. Guterstam (eds), 1997. Ecological Engineering for Wastewater Treatment. 2nd Edition. Lewis Publishers. (Link to publisher)

Etnier C, Refsgaard K.1999. Economics of decentralised wastewater treatment: testing a model with a case study. Paper presented to the conference: Managing the Wastewater Resource – Ecological Engineering for Wastewater Treatment, 7–11 June 1999, Ås, Norway.

Kuczera G, Coombes P. 2001. A systems perspective of the urban water cycle: new insights, new opportunities. Stormwater Industry Association 2001 Regional Conference, Port Stevens, NSW.

Otterpohl R. 2000. Design of Highly Efficient Source Control Sanitation and Practical Experiences. EURO Summer School DESAR, Wageningen, The Netherlands.

Wild U, Kamp T, Lenz A, Heinz S, Pfadenhauer J. 2000. Cultivation of Typha spp. in constructed wetlands for peatland restoration. Ecological Engineering, 17(1): 49–54.

Appendix 6 On-site systems – key features

Note: All costs are indicative only, may vary from site to site, and are stated in 2002 dollars.

System 1

This figure summarises the features of a traditional wastewater treatment system, with no water saving, black and grey water being treated in a single-chamber septic tank, output trickle-loaded to a seepage trench. It outlines the technical features and benefits and/or constraints.

System 2

This figure summarises the features of a modern wastewater treatment system, with no water saving, black and grey water being treated in a multi-chamber septic tank (ST) or improved ST with filter, output dose-loaded to a seepage trench. It outlines the technical features and benefits and/or constraints.

System 3

This table summarises the features of a modern wastewater treatment system, with no water saving, black and grey water being treated in a multi-chamber septic tank (ST) or improved ST with filter, output dose-loaded to a Wisconsin mound. It outlines the technical features and benefits and/or constraints.

System 4

This table summarises the features of a modern wastewater treatment system, with no water saving, black and grey water being treated in a multi-chamber septic tank (ST) or improved ST with filter, output dose-loaded to a seepage trench. It outlines the technical features and benefits and/or constraints.

System 5

This table summarises the features of a wastewater treatment system, with no water saving, black and grey water being treated in a multi-chamber septic tank (ST) or improved ST with filter, output to a sand or textile filter, dose-loaded to a sub-surface irrigation. It outlines the technical features and benefits and/or constraints.

System 6

This table summarises the features of a wastewater treatment system, with no water saving, black and grey water being treated in a multi-chamber septic tank (ST) or improved ST with filter, output to a constructed wetland, dose-loaded to sub-surface irrigation. It outlines the technical features and benefits and/or constraints.

System 7

This table summarises the features of a modern wastewater treatment system, with no water saving, black and grey water being treated in an AWTS, output dose-loaded to sub-surface irrigation. It outlines the technical features and benefits and/or constraints.

System 8

This table summarises the features of a wastewater treatment system, with no water saving, black and grey water being treated in AWTS, output dose-loaded to sub-surface irrigation. It outlines the technical features and benefits and/or constraints.

System 9

This table summarises the features of a wastewater treatment system, with no water saving, black and grey water being treated in a multi-chamber septic tank (ST) or improved ST with filter, output dose-loaded to an evapo-transpiration seepage bed. It outlines the technical features and benefits and/or constraints.

System 10

This table summarises the features of a wastewater treatment system that require two separate systems – one for a composting toilet (compost chamber with manual handling to safe burial of compost) and the other for grey water, which is treated in a ST or grease trap, output dose-loaded to a sub-surface irrigation to a constructed wetland. It outlines the technical features and benefits and/or constraints.

Appendix 7 System Matrix

System Matrix

Possible criteria Fully centralised system Combination of on-site
and centralised system
Cluster system Fully on-site systems
Physical characteristics of site
Limitation of site or area, (eg, soils climate, groundwater aspect proximity) Not applicable The on-site component acts as pretreatment to the central system. This is likely to be a septic tank and/or pump and sump. Suitable area of land required on site. Some limitations of site. Septic tank to be accessible for pumpout servicing Suitable local site location and area required. Specific site conditions and area required, especially for return of treated wastewater and sludge to the ecosystem Site area, soils, topography and ground water conditions may limit on-site options. Septic tank to be accessible for pumpout servicing
Resilience to natural hazards Vulnerable to natural hazards such as earthquakes and floods Vulnerable to natural hazards such as
earthquakes and floods
Impact of natural hazard event less than a fully
centralised system. Flood risk
More resilient to natural hazard events. Flood risk
Ecological
Impact on surface and ground water, aquatic and other habitats, ecosystem services, soils Large conventional sewer network resulting in urban impacts. Older networks can result in stormwater infiltration overflows from sewers and pumping stations. Site and technology specific. Must meet RMA consent requirements. Ecological impact of emissions (treated wastewater, sludges and any odorous gases) will depend on standard of treatment, plant management and sensitivity of receiving ecosystem and proximity of human neighbours Modified or alternative sewer network required. Site and technology specific. Overflows from infiltration substantially reduced or eliminated. Must meet RMA consent requirements. Ecological impact of emissions (treated wastewater, sludges and any odorous gases) will depend on standard of treatment, plant management and sensitivty of receiving ecosystem and proximity of human neighbours. Small scale modified or alternative sewer network required. Overflows can be substantially reduced by good design and construction. Site and technology specific. Must meet RMA consent requirements. Each cluster handles a smaller volume than a centralised system, so the ecological impact is likely to be less. Impact will depend on standard of treatment, plant management, sensitivity of receiving ecosystem and proximity of human neighbours. No sewer networks required. Ecological impact all on-site. Very dependent on system technology and ongoing management. Will also be depend on sensitivity of receiving ecosystem.
Ecological restoration opportunities Highly treated wastewater could be used for
wetland resortoration
Highly treated wastewater could be used for
wetland restoration
Highly treated wastewater could be used for
wetland restoration
On-site wetlands could be fed with secondary
treated wastewater
Resource efficiency – closing of ecological cycles Often not considered by central authority. Very dependent on design and management of the system Often not considered by central authority. Very
dependent on design and management of the
system
Local sewer network may save pumping
and consequent energy demand. More recent
systems are designed for efficient resource use
and closing of ecological cycles
No sewer networks required. Greater opportunity
for closing of nutrient cycles
Water recycling Possible to achieve but would require high-quality treatment as well as provision of separate and readily identifiable reticulation to users Possible to achieve but would require high-quality treatment as well as provision of separate and readily identifiable reticulation to users Possible, but would require high-quality treatment and separate reticulation to user. Very possible, but would require high-quality treatment. Greywater recycling for toilet flushing and garden watering is a viable technology already in use in NZ
Compatibility with Māori perspectives
Issue of passage through land May be an issue but needs to site specific analysis. RMA process will address these issues Maybe an issue - site specific.
RMA process will address these issues
Cluster schemes provide opportunity for local land application and ecosystem re-entry  
Protection of mauri Dependent on siting and ecosystem re-enty type Dependent on siting and ecosystem re-entry type Dependent on siting and ecosystem re-entry type All effluent applied to land, hence likely compatible.
Unlikely to be a problem
Other cultural concerns
Local stewardship/ responsibility Central system disconnects waste producers from relevant ecosystem's realities Central system disconnects waste producers
from relevant ecosystem's realities
More opportunities to 'tailor fit' local cultural
requirements. Community has closer link to
receiving ecosystem
Possible to fit to individual's cultural requirements.
Very close links with receiving ecosystem
"Neighbourly" conflicts possible
Re-use of reclaimed water Likely to be a general cultural difficulty Likely to be a general cultural difficulty Likely to be a general cultural difficulty Because of individual choice, expect wider
acceptance
Public health
Operational safety Generally a very high standard of public health safety Generally a very high standard of public health safety. Generally a very high standard of public health
safety.
Dependent on technology and management. Approved systems that are well designed and subject to an inspection and management programme will be safe
Impacts on community health Central systems generally remove and treat wastewater well away from public contact, thus minimising health risks. Treated effluent discharge to receiving waters must meet health standards for recreation and shellfish harvesting. Stormwater overflows from sewer networks can pose short term health risks. Strict controls apply to land application by spray irrigation Central systems generally remove and treat wastewater well away from public contact, thus minimising health risks. Treated effluent discharge to receiving waters must meet health standards for recreation and shellfish harvesting. Stormwater overflows from sewer networks can pose short term health risks. Strict controls apply to land application by spray irrigation Local cluster schemes mean public closer to treatment and re-entry areas. Health risk low if management of treatment and re-entry system maintained at a high standard Risk low provided well designed and managed. Neglected systems can give rise to failure conditions, effluent surfacing, and high health risk to property dwellers and immediate neighbours
Residual management All residual products are managed centrally All residual products are managed centrally All residual products are managed by the cluster management agency Treated wastewater is managed on-site. Sludge must be managed off-site at an approved location. Composting toilets not favoured in urban areas by MoH
The technical system
Reliability Usually reliable. Older sewer networks can present a significant infiltration problem. New networks are also subject to infiltration Reliable. Infiltration can be minimised Most modern systems will be reliable. More
dependent on management structure, knowledge
and skill
Dependent on technology quality, knowledge and skill, and a regular inspection and management programme
Serviceability Usually easily serviced, although dependent on
system design and management structure
More geographically dispersed, therefore serviceability more difficult. Dependent on system design and magagement structure Usually easily serviced, although dependent on system design and management structure Dependent on type of system installed and servicing protocol
Operational requirements Operated by trained technicians Operated by trained technicians Should be operated and maintained by trained technicians
 
Operation and maintenance requirements must be diligent to avoid failure. Council organised management programme or independent operation and management contracts will reduce such risk of failure
Engineering life of the system Long life On-site components possess a medium to long life, whilst central components possess a long life Medium to long life. Medium to long life when subject to a management programme
Resilience to acts of vandalism. Depends on system design and management. Because of centralised location, easier to reduce acts of vandalism Depends on system design and management.
Because of mostly centralised location, easier
to reduce acts of vandalism
Generally located away from public eye, creating higher risk of vandalism Systems are not normally secure, but vandalism not normally a significant problem
Linkages with other opportunities and services (eg water supply) There are opportunities to recycle water and nutrients, recover energy, restore/create wetlands and provide an ecological education facility. Short-term economics usually constrains implementation There are opportunities to recycle water and
nutrients, recover energy, restore/create
wetlands and provide an ecological education
facility. Short-term economics usually constrains
implementation
There are opportunities to recycle water and nutrients, recover energy, restore/create wetlands and provide an ecological education facility. Short-term economics usually constrain implementation There are opportunities to recycle water and nutrients, recover energy, restore/create wetlands and other on-site landscaping. Implementation is dependent on individual motivation, funding and regulatory constraints
Ability to be changed
Extendability Depending on design, most of the older, centralised systems are not so extendable or adaptable to changing requirements. Sewer infrastructure (and required flow velocities) can restrict future changes to other parts of the system. Land can be limiting. Infrastructure locks in system capacity, limiting adaptability. Normally adaptable to trade waste inflows Depending on design, these system tend to be more recent and therefore extendibility may have been included in the design Depends on design, but more likely to be adaptable due to being a smaller system. Funding may limit extendibility and adaptability It is the individual property owner's responsibility to build in extendability and adaptibility. Most likely funding but also land area will limit the ability to respond to changes. On-site secondary treatment systems have limited opportunity to be extended for increased loading
Adaptability/flexibility These systems tend to be a little more adaptable due to the lower cost of reticulation. However, adaptability will be rather limited. Normally adaptable to trade waste inflows
Management
Ownership Normally owned and managed by city/district council Normally owned and managed by city/district council Can be owned and managed by city/district
council or by corporate body
Owned by property owner. Normally managed by property owner, although owners can form a body corporate to oversee O&M
Convenience Having all the operation at a central
location simpifies management requirements
With some components on-site and most central,
management will be less convenient
Management of cluster systems may be perceived
as less convenient than a larger centralised
system and more convenient than on-site systems. Centralised management of a group of cluster systems is recommended
Management requirements will depend on type of
system installed. Traditionally, management responsibility lies with the property owner. Management may be by contract, or by a management agency, thus providing maximum convenience to the owner
Operation and maintenance implications
 
The centralised nature of this system makes
operation and management uncomplicated
The operation and maintenace programme will need to be designed for a combination of on-site and centralised requirements   Operation and maintenance requirements will depend on the type of system installed. Servicing contracts are often employed, and inspection and management programmes are recommended to ensure long life of the system
Economic factors
Capital and operating costs City/district council responsibility. Capital and annual operating costs are normally evenly spread across the community served. User-pays possible with water metering City/district council responsible for off-site costs, and maybe on-site costs. In some situations
on-site costs may lie with property owner. Capital and annual operating costs are normally
evenly spread across the community served. User-pays possible with water metering.
Capital costs may be the responsibility of the developer or city/district council. Operating costs may be the responsibility of city/district council or a specially constituted corporate body Capital and operating costs are the responsibility of the property owner. Where a council or body corportate management programme is in place, annual charges will be levied for O&M
Funding Rates Rates Rates, or built into purchase price Individual capital funding, and individual or body corporate or managment agency fees for O&M
Local community impacts
Level of local control Community generally has minimal input into the
design, operation and management of these
systems
Community generally has minimal input into the design, operation and management of these
systems
More opportunity for community input into the
design, operation and management of these
systems
Greater degree of control lies with individual property owners.
Need for external expertise/management Usually a significant external input into the
design, operation and management of these
systems
Usually a significant external input into the
design, operation and management of these
systems
External expertise for the design is normally
required. Management can be local or
centralised
External expertise for technology selection and design is normally appropriate. Management can be on-site or centralised
Community change
Pressure for future growth Stimulates urban growth, including commercial
and industrial growth
Stimulates urban growth, including commercial and industrial growth The cluster system will enable domestic
localised growth. Less conducive to
commercial and industrial growth
Local geophysical and hydrological conditions can restrict urban growth. Recent systems can overcome some of these constraints
Capacity to absorb growth Depends on both total system design capacity and
individual capacity for each component. Modern
systems can be designed to accommodate future
growth
Depends on both total system design capacity and
individual capacity for each component. Modern
systems can be designed to accommodate future
growth
Cluster systems tend to be designed for a given cluster of homes. May be possible to absorb some growth, or additional cluster systems may be require. Growth will be dependent on the suitability of the property's site for on-site management. However, growth within site boundaries is very rarely an issue
Other potential benefits
Leisure and recreation Restored wetlands may be integrated with an
urban park. Health risks would have to be
minimised by appropriate pre-treatment prior to wetland re-entry
Restored wetlands may be integrated with an
urban park. Health risks would have to be
minimised by appropriate pre-treatment prior to wetland re-entry
Restored wetlands may be integrated with an
urban park. Health risks would have to be
minimised by appropriate pre-treatment prior to wetland re-entry
N A
Education Opportunities to develop community education
activities centred on wastewater, and social and
ecological issues
Opportunities to develop community education
activities centred on wastewater and social and
ecological issues
Opportunities to involve local community in
educational activities centred on wastewater
and social and ecological issues
Opportunities to educate community to take greater responsibility for their waste
Research Many research opportunities to study the resource value of wastewater Many research opportunities at the centralised level to study the resource value of wastewater Many research opportunities at the local
level to study the resource values of
wastewater
Many research opportunities at the individual level to study the resource values of wastewater
Formal processes
Familiarity to decision-makers Decision-makers are familiar with these types of
systems and traditionally place confidence in
them
Decision-makers are less familiar with these types of systems but normally have confidence in them because of the final centralised management Decision-makers are less familiar with these
types of systems and subject such systems
to greater scrutiny
Decision-makers are familiar with on-site systems, but often very unfamiliar with recent innovations and the benefits of inspection and management programmes
Technical demands Requires expert engineeering input for design.
Requires skilled operators
Requires expert engineeering input for design. Requires skilled operators Requires expert engineeering input for design
Requires skilled operators
Requires expert engineeering input for design
Requires trained inspection, operation and maintenance personnel
Public health service Strict health standards Strict health standards Strict health standards Strict health standards
Ease of the consent process Site and system dependent. Consenting process
usually well resourced
Site and system dependent. Consenting process
usually well resourced
Site and system dependent. Consenting process
usually less well resourced
Consent under council building controls.

Appendix 8 Examples of Decision Trees for Wastewater Systems

(a) Pit toilets

(Courtesy of Department of Conservation from: Standard of Practice for Backcountry Hut Toilets (draft)

Standard Solution Selection – Pit Toilets

This figure outlines a decision tree for a pit toilet. Has a site evaluation been carried out by a suitably qualified and experienced person? If not, obtain specialist advice. If yes, does the evaluation indicate low use toilet usage? If not, go to another chart. If yes, does the site evaluation indicate prohibition of human waste discharge? If yes, is a pump-out containment system applicable? If there is prohibition of human waste discharge, does the site evaluation indicate any site limitations? Seek specialist advice if this is the case. If not, is the soil depth sufficient for a pit toilet? (Go to another chart if not.) If yes, is groundwater at a depth sufficient for a pit toilet? (Go to another chart if not.) Does experience at the site indicate problems with pit toilets? If so, seek specialist advice; if not, use a standard pit toilet.

(b) Septic tank systems

(Courtesy of Department of Conservation from: Standard of Practice for Backcountry Hut Toilets (draft)

Septic tank systems

This figure outlines a decision tree for a septic tank system. Has a site evaluation been carried out by a suitably qualified and experienced person? If not, obtain specialist advice. If yes, does the evaluation indicate prohibition of human waste discharge? If so, is a containment system applicable? If not, does the site evaluation indicate any site limitations? If not, does the soil drain poorly? Does ground cover preclude subsurface disposal? If so, seek specialist advice. If not, Is the depth for the seasonal watertable greater than 1200mm with no limiting intermediate horizons? If not, seek specialist advice. If so, does the ground surface slope less than 20 degrees? If not, seek specialist advice. If so, does the soil drain rapidly? If so, seek specialist advice. If not, use the sub surface land application method.

Appendix 9 Example of protocol for conducting public meetings

Consensus Protocols for the Whaingaroa Wastewater Working Party

The following are the mediator/facilitator's understanding of the protocols under which the group is working:

  1. The personal behaviour ground rules set at the first mediation:
    • one speaker at a time
    • no interruptions
    • separate caucus when need be
    • working towards a resolution
    • stick to the kaupapa
    • "I" statements
    • everyone's issues to be respected
    • cultural protocols to be observed/respected.
  2. The Memorandum of Understanding which is now signed and describes the overall goal of the process must be referred back to.
  3. That members of the public are welcome to sit in the meetings and to participate if invited by the facilitator but not to be part of the decision making on specific options. Mana whenua are not "members of the public" but a hapü group with their own kawa for decision making.
  4. Decision making is worked towards by consensus ie. not by voting, but by a discussion based on developing common ground and developing a position we can all live with, without compromising any bottom lines.
  5. The media is not excluded but any formal statements by the group can only happen with full group approval, as individuals and groups need to be aware that separate media statements can damage trust in the process.
  6. From now on full minutes will be recorded by the Council secretarial service and circulated at least 7 days prior to the next meeting.
  7. That all meeting agendas are set and agreed to by the whole group.
  8. That all parties need to state clearly which hat they are wearing and whom they represent in this process.
  9. That peer review processes all data be designed by the whole group.
Footnotes:

22 EDU = equivalent domestic unit, representing a home with the average number of adults for a community. In this report 1 EDU = 2.65 adults. return

23 TA Olssen, H Stenstrōm, H Jōnsson. Occurance and persistence of faecal microorganisms in human urine from urine-separating toilets. In: Environmental Research Forum, vols 5-6, Transtec Publications, 1996, pp. 409-419. return