Assessing the ecological footprint of a large metropolitan water supplier – lessons for water management and planning towards sustainability – Sven Lundie University of New South Wales Manfred Lenzen University of Sydney Bransgrove, Charet and Sack Sydney Water Corporation

Contents  Motivation for applying the Ecological Footprint Concept  Ecological Footprint method  Calculation procedure of SWCs’ Ecological Footprint  Results  Structural Path Analysis  Conclusion

Motivation For Applying the Ecological Footprint Concept  Sydney Water is Australia's largest water and wastewater service provider Australia's largest water and wastewater service provider committed to ecologically sustainable development (ESD) committed to ecologically sustainable development (ESD) to implement the principles of ESD by developing long-term strategies and plans that are informed by community consultation to implement the principles of ESD by developing long-term strategies and plans that are informed by community consultation  Sydney Water has developed 32 ESD indicators  Need for one aggregated indicator

Ecological Footprint Definition The ecological footprint is: ‘the area of productive land, wherever located on Earth, that is needed to sustain the consumption of a population indefinitely’.

Consumption-Land-Use Matrix  Five consumption categories Food Food Housing Housing Transportation Transportation Consumer goods Consumer goods Services Services  Four land categories Energy land Consumed land Currently used land Land of limited availability

Different Ecological Footprint Methods Process AnalysisInput-Output Analysis Land use Land distur- bance Rees, 1992; Wackernagel (et al) (1993–2000); Barrett, 2001; Chambers and Lewis, 2001 Simpson et al (1998 and 2000) Bicknell et al (1998) Lenzen & Murray (2001) Bio- pro- duc- tivity

Land Use versus Land Disturbance Land use type Built Degraded pasture or crop land Mined land Cleared pasture and crop land Non-native plantations Thinned pasture Parks and gardens Native plantations Partially disturbed pasture (mostly arid) Weighting factor

Calculation procedure of SWCs’ Ecological Footprint  Hybrid Ecological Footprint calculation combining direct (on-site) land and emissions requirements of Sydney Water based on a detailed company auditdirect (on-site) land and emissions requirements of Sydney Water based on a detailed company audit with with all remaining higher-order requirements (for materials extraction, manufacturing, and services) based on input- output analysisall remaining higher-order requirements (for materials extraction, manufacturing, and services) based on input- output analysis  =  d + F (I-A) -1 × y

Results ECOLOGICAL FOOTPRINT Bicknell et al - Land use ECOLOGICAL FOOTPRINT Lenzen & Murray - Land disturbance Conversion Factor 0.01 ha/GJ68.5 ha/kt On-site All industry Total Land Greenhouse gas emissions

Structural Path Analysis M = F (I-A) -1 = F + FA + FA 2 + FA 3 + ….  24.04E El1 (1; 46.2%)(34.0%)  5.01E Wa1 (0; 9.6%)(7.1%)  2.10C Wa1 (0; 55.8%)(3.0%)  1.73E Ch1 (1; 3.3%)(2.4%)  0.93E Nb1 (1; 1.8%)(1.3%)  0.84E Ap1 (0; 1.6%)(1.2%)  0.58E Bl1 El1 (2; 1.1%)(0.8%)  0.57C El1 (1; 15.2%)(0.8%)  0.49E Is1 Fm1 (2; 0.9%)(0.7%)  0.38E Is1 Nb1 (2; 0.7%)(0.5%)  0.33S Bc1 Mp1 Ch1 (3; 5.4%)(0.5%)  0.28E At1 (1; 0.5%)(0.4%)

Breakdown into Commodities Supplied to Sydney Water  Electricity: 26.9 kha  Construction: 12.3 kha  Methane and premises: 7.4 kha  Chemicals: 4.3 kha

Decomposition of Production Layers On-site methane emissions CO 2 from power plants Coal mine seams, steel making

Summary of Results  Sydney Waters’ Ecological Footprint equals 78.1kha/a, i.e Land disturbance (26%) and GHG (74%) or Land disturbance (26%) and GHG (74%) or Land commodity components (electricity 34%, construction 16%, methane and premises 9% and chemicals 6%) Land commodity components (electricity 34%, construction 16%, methane and premises 9% and chemicals 6%) First seven path contribute more than 50% to SWC’s EF First seven path contribute more than 50% to SWC’s EF Major contributions to SWC’s EF are on-site or first order processes Major contributions to SWC’s EF are on-site or first order processes

Conclusions  Ecological Footprint calculation is improved by applying Input-output technique (system completeness) Input-output technique (system completeness) Land weighting factors Land weighting factors  Remaining uncertainties are in General General TradeTrade Land disturbance caused by climate changeLand disturbance caused by climate change This case study This case study Inability to incorporate ‘downstream’ impacts from effluent and biosolidsInability to incorporate ‘downstream’ impacts from effluent and biosolids

Conclusions – contd.  Management and planning relevance Greater insight in companies direct and supply chain impacts Greater insight in companies direct and supply chain impacts The ability to aggregate a number of different environmental aspects into a single, easily understood indicator The ability to aggregate a number of different environmental aspects into a single, easily understood indicator Useful as a communications tool Useful as a communications tool Engenders a sense of personal responsibility amongst its customers in their use of water Engenders a sense of personal responsibility amongst its customers in their use of water

Thank you!