shac water conservation - maggie lawton
DESCRIPTION
Design Criteria •Water efficient fittings and appliances •On-site water capture and reuse •Water supply flow rates optimised to balance required performance and conservation •Local retention of stormwater runoff, stormwater treatment train with consideration of raingardens, roofgardens and swales •Wastewater minimised and/or reused; information on water use readily available •In-house water supply flow rate optimised •Plumbing system designed for water and energy efficiency •Site design recognition of local soil and climate conditions and low water use garden design applied.TRANSCRIPT
Water Conservation
SHaC Video-conference
14 May 2008
Water in the built environment
• Water Supply
• Wastewater treatment
• Stormwater treatment
Judging Criteria
• RESEARCH & DESIGN & DEVELOPMENT 30%• 1. Teamwork and Collaboration within Tertiary organisation,
and with Industry, Local Government, and other Teams• 2. Project Management: Research, Planning and Process• COMMUNITY CONNECTION 25%• 3. Community Engagement• 4. Communication of design and rational to community• DESIGN AND ARCHITECTURE 45%• 5. Health• 6. Energy• 7. Material and Resource Use• 8. Water & Waste Management• 9. Site and Environment• 10. Architecture and Affordability
Hydrologic Cycle
Water Criteria
• 90 l/pp/pd design critera is achievable without supplementary supply
• Stormwater flows attenuated
• Wastewater reduced where possible
• Innovation being sought, in particular integration of water services.
What we are looking for• Safe and healthy water services to the home• Maximising water use efficiency• Providing resilience to the system through supplementary
supply• Retaining stormwater on-site, allowing infiltration• Integrating services where possible• Pushing the boundaries, gently; showing innovation• Understanding (not necessarily agreeing with) regulatory
constraints and working with regulators where required• Demonstrating how design criteria have been developed to
meet performance targets• Integrating the water services where possible and
considering whether integration with other services.
Social Considerations
• Less than 0.08% of all the Earth's water is available for biological life. Yet over the next two decades human use is estimated to increase by about 40%.
• Local Government Act requires thinking sustainably across the four pillars of wellbeing – cultural, environmental, social and economic.
Building resilience
• Reducing competing demands for water in parts of the Country where water resources are constrained.
• Reducing the need for further large water supply systems which cause changes to the water cycle and do not operate in harmony with natural water cycles and water catchments.
• Anticipating potential climate related changes and resulting water cycle disturbances
• Reducing the contribution of leaks and spills from wastewater on declining water quality in New Zealand
• Recognising that some water sources are not renewable in the short-term, for example groundwater is generally non-renewable for practical purposes
Cost savings
• Saving on capital costs through delaying or eliminating infrastructure development.
• Achieving cost savings in wastewater management through reducing the water that goes through the system.
• Saving cost associated with energy through reducing in-house hot water use.
• Saving costs associated with energy and maintenance in both the treatment of water to a potable standard and its reticulation.
• Saving energy and maintenance costs in the reticulation and treatment of wastewater.
life supporting resources
declining
consumption of life supporting resources
rising
“We can’t solve problems by using the same kind of thinking we used when we created them” Albert Einstein.
From this….
To this…
We could be going from: This…..
To this
Water Use Efficiency
Typical breakdown of domestic water use
Comparison of daily per capita water uses* =metered with volumetric pricing
Council Daily Per Capita Water Use Figure
Nelson 160*
Waitakere 167*
Rodney 179*
Metrowater (Auckland City) 184*
Manukau 189*
Papakura 190*
Kawerau 214
Upper Hutt 227
Tauranga 265*
Christchurch 333
South Taranaki 450
Kaikoura 648
Kapiti 650
Queenstown Lakes District 750
Current technologyTechnology including
Rainwater tanks
Greywater Reuse
Reduced or low flow devices
Pressure reducers
Tap aerators and flow restrictors
Dual flush/low flush toilet Water efficient appliancesWELS rating system should be in use this
year
Smarter use of Water
ProductsCosts
$sCosts with installation
Water savings % of
total use
Accumulative water savings %
of total use
Gismo 2 5-10 5Tap Aerators 10 5-10 10Outdoor hose washers
2 2-5 12-15
Low flow shower head75 150 10-15 22-30
Dual Flush Toilets
(<5l)225 300 10-15 27-40
4 star rated washing machine 1200 10 37-50
Rain barrel 400 litres or300 10-15 47-60
Rain tank
4500 litres or4000 4500 40-60 75 plus
Wastewater recovery system 3000 4000 20-40 60 plus
Relative increasing cost and difficulty
Tap aerators and shower flow restrictors
Stop household leaks
Dual flush toilet
Rainwater tank
Wastewater recycling and composting toilets
Rainwater barrels
Low flow shower head
Water conservation gardening
Water efficient appliances Water
conservation behavior
Wat
er u
se e
ffic
ienc
y
Schematic of DM options against cost and difficulty of implementation for the domestic user
Rainwater from all roofs is collected in this 25,000 litre tank. It is used for toilet flushing on ground floor, for urinals and for irrigation of glasshouses.
Landcare’s water management
Kapiti Coast District Council
• Public education
• Wide ranging education progs
• & free services,eg. green gardener
& plumber, and garden show
• Subdivision Code of Practice promoted low impact urban design
• Proposed a District Plan change- two acceptable solutions which promote water conservation
• But: no metering and still have 650 l/pp/pd
0
50
100
150
200
250
300
350
400
450
Business As Usual 12000 litre raintank(toilet, laundry and
outdoors)
4420 litre raintank(toilet, laundry) and
greywater (outdoors)
Wa
ter
us
ag
e (
l/p
/da
y)
Leakage (assuming popn of 36000)
Commercial use (assuming popn of 36000)
Residential use
Modeled water reduction for Kapiti
Composting Toilets
·
·
Wastewater Management
Stormwater Managament
Prevention Techniques
• Landscaping– rain gardens, swales, absorbent materials
• Green Roofs
• Pervious Pavement
• Ponds and Wetlands
• Infiltration Trenches
Common site-level Best Management Practices
Water Quality Friendly Streets
Source: City of Portland Water Quality Friendly Streets Program. http://www.portlandonline.com/bes/index.cfm?c=32066
The Kapiti Coast District Council experience in changing the rules of
the game for subdivision & development
Out with the old and in with the newOut with the old and in with the new
• Living areas face the street• Permeable fences• Houses facing reserve/public
open space• Located on site for solar
access• Each house has private space
outside to rear or back of property
• Narrower carriageways• Located near planned railway
station• Building materials chosen for
long term durability
On the ground change
• Low flow showerheads• Watersmart two tank
system– Rainwater for use in gardens– Town supply for use in
house• Greywater collected for
watering lawns• Uses covenants on the title
to ensure systems are maintained
On the ground change
Example of 500m2 lots
SMA 254%
61%
61%
48%
61%
53%
55%
Permitted Activity Route, North Shore
• “Off-the-shelf” standard solutions
• SMA & Activity
• Preferred mitigation methods
• Rain tanks
• Bio-retention
• Provide multiple benefits
• Practice notes to aid with design (Source:Maplewood, Minisata)
Bio-retention• Rain gardens, SW planters, Bio-retention swales, Tree Pits• Benefits:
– Water volume reduction, – Peak flow control, – Water quality, – Amenity
• Min Design • Requirements:
– Min depth 600mm of planting soil– 8% of area (or 5%)
• Practice note to help with design• Gardens not treatment devices
Water Quality Friendly Streets
Curb Cut w/Pad
Council documentation
– Engineering standards
– Council Engineering Manuals
– Verification Methods and
Acceptable Solutions
– Information Pamphlets and
Brochures
– Practice Notes/Design
Guidelines
Based on work of Prof Hans Schreier
A Traditional Approach
• >Impervious Surfaces• < Buffer Zones• Stormwater Piping• Large scale infrastructure• End of Pipe Treatment• Point Source Pollution• Expanding Water Supplies• Focus – Single Pollutants• Water Use of Human
Activities• Government Management
A Sustainable Approach
• < Impervious Surfaces• > Buffer Zones• Creating biological solutions• On-site solutions• Detaining Stormwater• Non-Point Source Pollution• Controlling Demand• Source Control• Water for Environmental
Services• Community Involvement
Design Criteria• Water efficient fittings and appliances• On-site water capture and reuse• Water supply flow rates optimised to balance required
performance and conservation • Local retention of stormwater runoff, stormwater treatment
train with consideration of raingardens, roofgardens and swales
• Wastewater minimised and/or reused; information on water use readily available
• In-house water supply flow rate optimised• Plumbing system designed for water and energy efficiency• Site design recognition of local soil and climate conditions
and low water use garden design applied.
Website resources• http://www.level.org.nz• http://www.sustainablehouseholds.org.nz/actionpdfs/
save_water_action.pdf• http://www.smarterhomes.org.nz/water/• http://www.ecobob.co.nz/EcoBusiness/Browse.aspx also good
for products and services• http://www.waitakere.govt.nz/CnlSer/wtr/wtrsavetips.asp• http://www.ecomatters.org.nz/09_Water/091_Water/
091d_Water_06_top_10_tips.htm • http://www.ecan.govt.nz/Our+Environment/Energy/YourHome/
homeimprovement/hot-water.htm for hot water saving tips• http://www.bethedifference.gw.govt.nz• http://www.ccc.govt.nz.waterwause/story2.497.cfm?• http://www.greenpagesaustralia.com.au• http://www.consumerbuild.org.nz/publish/maintenance/kitchen-
bathroom-plumbing.php
Definitions
Residential Built Environment
“The residential built environment consists of the buildings and supporting infrastructure that together constitute the surroundings in which people dwell. It includes, therefore, not only people’s dwellings but other neighbourhood buildings. It also includes the arrangement of infrastructure that service dwellings and the neighbourhoods in which those dwellings are situated.”
Sustainability and Affordability
“In achieving sustainability of residential built environments the focus is on the sustainability of individual dwellings but also the neighbourhoods in which they are situated. The goal is to make improving the sustainability of dwellings and neighbourhoods both affordable and cost-competitive.”
Systems
Industry,
Infrastructure,
Government,
Consumers
Pull based on market and needs
Energy
Water
IEQ
Pull based on prioritised systems and HSS
Market Transformation – pan communication and alignment
Policy and Regulation – pan regulatory involvement
Beacon’s Operating Model
Neighbourhoods
New Homes
Retrofit Homes
BEACON WATER TARGETS
1. All Homes - reducing per capita demand
for reticulated water by 40% and council
mains supply by 50%.
2. All Homes & Neighbourhoods – Effective
management of three waters to create a
more resilient water system
Nation
Region
Neighbourhood
Home
City