Urban Water Security Research Alliance Life Cycle Assessment Perspectives for Total Water Cycle Planning Joe Lane Total Water Cycle Management Planning Science Forum, 19-20 June 2012
Research Outcomes Research goal How can LCA inform the TWCM process…? Findings • poor externalities accounting will lead to unintended consequences • poor system boundary definition will lead to unintended consequences and/or missed opportunities • LCA environmental breadth provides future insight • implementation is practical • interpretation is challenging • certain improvements would greatly increase the relevance/benefits
TWCP – Caboolture scenarios Existing Caboolture urban area • 61% population growth (43,000p) • nutrient and water supply constraints Analysis = applied to new population catchment stormwater water supply wastewater TSS, TP, TN 1 raintanks -- reduced by STP growth (T,L,E) min required 80/60/45% STP growth 2 reveg ∆ TSS, TP, TN raintanks farming BMP 80/60/45% (T,L,E) next best WW agriculture enhanced raintanks 3 WSUD (L) STP growth reveg more farming BMP stormwater harvesting and reuse ambitious WW reuse urban areas
Detailed System Boundary & Data system boundary catchment mgmt / WSUD • construct + operations • N/P balances from TWCMP • manufacture and supply of end use profile materials, chemicals, • Smart Water research power rainwater tanks and dams • water use = excluded • latest Aus research treatment plants (WTP, STP, AWTP, SWH, Desal) • detailed data from GCW + Sth Cab; SWH reuse = gap • fugitive emissions science; micropollutant data other aspects • insight from GCW study + more recent data
Improvements Affect the Tradeoffs Analysis potable water potable water potable water potable water TN reduction TN reduction TN reduction TN reduction Greenhouse gas emissions Greenhouse gas emissions Greenhouse gas emissions Greenhouse gas emissions savings savings savings savings to Cab Rv to Cab Rv to Cab Rv to Cab Rv (ML/y) (ML/y) (ML/y) (ML/y) (t N/y) (t N/y) (t N/y) (t N/y) (kt CO2e/y) (kt CO2e/y) (kt CO2e/y) (kt CO2e/y) ‘typical’ pow er ‘typical’ pow er ‘typical’ pow er ‘typical’ pow er pow er models developed for this study pow er models developed for this study pow er models developed for this study pow er models developed for this study use data use data use data use data scope 1,3 scope 1,3 scope 1,3 scope 1,3 fugitive GHG emissions (scope 1); supply of fugitive GHG emissions (scope 1); supply of fugitive GHG emissions (scope 1); supply of fugitive GHG emissions (scope 1); supply of excluded excluded excluded excluded chemicals & construction materials (scope 3) chemicals & construction materials (scope 3) chemicals & construction materials (scope 3) chemicals & construction materials (scope 3) mains mains mains mains mains mains mains mains avg' grid avg' grid avg' grid avg' grid desal desal desal desal excluded excluded excluded excluded excluded excluded excluded excluded supply supply supply supply supply supply supply supply 746 746 746 746 2 2 2 2 2 (1) 2 (1) 2 2 2 (+9%) 2 (1) 2 (1) 7 (1) 7 (1) 15 (2) Scenario 1 Scenario 1 Scenario 1 Scenario 1 746 746 746 746 12 12 12 12 4 (3) 4 (3) 4 4 5 (+42%) 5 (2) 5 (2) 11 (3) 11 (3) 18 (3) Scenario 2 Scenario 2 Scenario 2 Scenario 2 2,764 2,764 2,764 2,764 13 13 13 13 4 (2) 4 (2) 4 4 7 (+80%) 7 (3) 7 (3) 9 (2) 9 (2) 13 (1) Scenario 3 Scenario 3 Scenario 3 Scenario 3 • improved data makes a difference • mains supply matters • predicting the marginal grid source is problematic
Broader Enviro Scope Identifies Key Issues Scenario 1 Scenario 2 Scenario 3 100% 75% 50% 25% 0% Freshwater Eutrophic'n Marine Terrestrial Global Ozone Fossil Fuel Minerals Photochem Particulates ‐ 25% Extraction Potential Ecotox Ecotox Warming Depletion Depletion Depletion oxidants formation ‐ 50% ‐ 75% ‐ 100% Freshwater Eutrophic'n Marine Terrestrial Global Ozone Fossil Fuel Minerals Photochem Particulates Extraction Potential Ecotox Ecotox Warming Depletion Depletion Depletion oxidants formation WW direct sources 0% ‐ 77% ‐ 105% ‐ 122% 0% 0% 0% 0% 0% 0% discharge irrigation ‐ 100% ‐ 1% 0% 173% ‐ 1% 0% ‐ 1% ‐ 3% 0% 0% fugitive 0% ‐ 27% 0% 0% 0% ‐ 16% 0% 0% 0% ‐ 2% gases indirect sources energy 0% 3% ‐ 4% 6% 74% 101% 74% 28% 23% 54% chemicals 0% 1% 8% 36% 23% 14% 21% 57% 10% 45% 0% 0% 0% 7% 4% 1% 6% 18% 67% 3% construct'n Contribution to the change between Scenario 1 & Scenario 2
Major WWT Contribution to Enviro Burden System boundary = all mains supply; all wastewater discharge; all stormwater discharge 100 biosolids impact category result % contributionto total to disposal 50 0 Freshwater Eutrophic'n Marine Terrestrial Global Ozone Fossil Fuel Minerals Particulates Extraction Potential Ecotox Ecotox Warming Depletion Depletion Depletion formation mains sewerage rainwater stormwater water supply + WWT tanks 150 biosolids to farms % contributionto total impact category result 75 0 Freshwater Eutrophic'n Marine Terrestrial Global Ozone Fossil Fuel Minerals Particulates Extraction Potential Ecotox Ecotox Warming Depletion Depletion Depletion formation ‐ 75
Different Benchmarks give Different Perspectives % change to MBRC urban water system 30% 20% 10% 0% ‐ 10% Freshwater Eutrophic'n Marine Terrestrial Global Ozone Fossil Fuel Minerals Particulates Extraction Potential Ecotox Ecotox Warming Depletion Depletion Depletion formation Scenario 1 Scenario 2 Scenario 3 % change to Australian economy 0.01% 0.00% Freshwater Eutrophic'n Marine Terrestrial Global Ozone Fossil Fuel Minerals Particulates ‐ 0.01% Extraction Potential Ecotox Ecotox Warming Depletion Depletion Depletion formation ‐ 0.01% ‐ 0.02% ‐ 0.02% Scenario 1 Scenario 2 Scenario 3
Conclusions Offsets matter • avoiding mains water use net environmental benefit • water and nutrient offsets (e.g. WW reuse) even better GHG accounting needs improvement • GHG intensity… if analysis limited to scope 2 (energy) or $/CO 2 Life cycle thinking helps • should explore sensitivity to system boundary selection • broad environmental scope provides insight to future challenges • improved impact models would greatly increase their relevance Benchmarking is useful but needs improvement • improvements are ongoing; are there other meaningful approaches…? LCA suited to more focussed comparison of specific options • rigour highlights key gaps in data/understanding • quantifying tradeoffs provides transparency
Urban Water Security Research Alliance THANK YOU Particularly: • Co-author – Paul Lant (UQ) • Andrew Sloane, Phil Wetherell, Niloshree Mukherjee, Lavanya Susarla (MBRC/UW) • Kelly O’Halloran (GCW) • Cara Beal, Rodney Stewart (Smart Water Research Centre) • Murray, Luis, Esther, Grace, Meng, Ashok and Shiroma (CSIRO) • Julien Reungoat and many at AWMC • Nicole Ramilo and Tony Weber (BMT-WBM) • David de Haas (GHD) www.urbanwateralliance.org.au
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