Urban Water Security Research Alliance

Transcription

1 Urban Water Security Research Alliance Cost of Pollution and Options Evaluation Case Study of Moreton Bay Regional Council Total Water Cycle Management Plan Murray Hall Total Water Cycle Management Planning Science Forum, June 2012

2 OUTLINE Aim Step 1. Comparing water supply option including pollution costs Step 2. Calculating pollution costs Next step and other applications

3 AIM To consider environmental impacts and the cost of water supply for options evaluation. Important environmental impacts for water supply options include greenhouse gas emissions and waterway health Water quality impacts account for most of the willingness to pay for natural resource management (Binney 2010) Pollution trading suggests the ability to monetize pollution loads Cost to supply water Cost of water pollution Extended cost of water supply Cost of GHG pollution

4 STEP 1.COMPARING WATER SUPPLY OPTIONS Extended Cost Effectiveness Analysis National Water Commission and Draft TWCMP Guidelines, although note there are few examples beyond GHG emissions Water Supply A $Capital & operating cost $Pollution costs Extended with pollution costs Water Supply B $Capital & operating cost $Pollution costs Capital and operating B < A Capital and operating AND Pollution A< B Cost ($)

5 CASESTUDY Moreton Bay Regional Council Evaluation of the Draft TWCMP options for Caboolture catchments with the Caboolture Identified Growth Area (CIGA) including combinations of the following water supply options: Recycled Water for Dual Reticulation and Public Open Space irrigation (POS) Potable Recycled Water (PRW) Grid Water Rainwater tanks Stormwater Harvesting for Dual Reticulation and Public Open Space irrigation

6 POLLUTANT COSTS FOR NO WORSENING Pollutant Cost per tonne ($/t) Total Suspended Solids 213 Total Nitrogen Total Phosphorus Carbon Dioxide 23 Based on Commonwealth Govt Clean Energy Futures which is in the range of values calculated for targets for the MACC for greenhouse gases (McKinsey Australia)

7 WATER SUPPLY AND EXTENDED COST Cost per Unit of Water Supply ($2011 NPV/ML) Potential change of ranking by considering pollution costs Project Cost Extended Cost Effectiveness Water supply cost Extended cost (water supply cost +pollution cost) Extended cost is greater (although difference is small) for these water supply options because they increase pollution loads Extended cost is less for these water supply options because they reduce pollution loads

8 Cost per Unit of Water Supply ($2011 NPV/ML) CONTRIBUTION OF POLLUTANT COSTS Total nitrogen abatement by the water supply options provides a relatively large cost saving compared to the cost to supply water GHG TP TN TSS Project Water Cost supply cost 0 The cost for other water supply pollutant loads are small compared to costs to provide the water supply.

9 STEP 2. CALCULATING POLLUTION COSTS Marginal Abatement Cost Curves (MACC) Hall, M. R. (2012) The Cost of Pollution: Supporting Options Evaluation and Cost Effective Pollution Reduction UWSRA Technical Report (submitted) Hall, M. R. (2012). "Marginal Abatement Cost Curves and Cost Effective Water Pollution Management." Environmental Science & Policy (in review). Each box represents a mitigation option Average pollutant reduction cost for the load reduction target Cost per unit of pollutant reduction Amount of pollution reduction Load reduction target

10 MACC FOR TOTAL PHOSPHORUS (TP) Based on options identified in the Draft TWCMP for Caboolture and CIGA Abatement Cost ($/tonne) Abatement benefit $ /tonne Weighted average abatement cost $ /tonne Rural BMP Buffer strips Based on willingness to pay for no worsening (Binney 2010) Purified Recycled Water WSUD Retrofit to Best Practice WSUD to Best Practice Targets Pollution Abated (tonnes) Recycled water POS South Caboolture STP Recycled water POS New STP CIGA Load Reduction target 369 tonne Load reduction target for no worsening

11 Abatement Cost per tonne of pollutant ($AUD2010) Abatementbenefit $ /tonne UNCERTAINTY Large difference in TP abatement cost for WSUD and this affects the weighted average price for total phosphorus because it is one of the main abatement options Abatement Cost ($/tonne) Abatement benefit $ /tonne Weighted average abatement cost $ /tonne Rural BMP Buffer strips Purified Recycled Water WSUD Retrofit to Best Practice WSUD to Best Practice Targets Pollution Abated (tonnes) Recycled water POS South Caboolture STP Load Reduction target 369 tonne Recycled water POS New STP CIGA

12 CONCLUSIONS TWCMP water supply evaluation can use a single dollar metric to capture water supply and its pollution impacts Pollutant cost (savings) can be up to 50% of the extended cost for options such as recycled water Pollutant costs are less than 20% for most options considered and GHG emissions less than a couple of percent GHG cost may increase if the marginal water supply is desalination but unlikely to be more than 5-10% of extended costs of a water supply option

13 CONCLUSIONS Consideration of abatement options for all catchments in the TWCMP may lower abatement costs by considering more options than those just within Caboolture/CIGA catchment May require prioritisation of high environmental value waterways Large difference in abatement costs suggests cost savings through policy measures such as Water Quality Trading eg, cheaper for wastewater treatment plant to pay for abatement in catchment than upgrade the plant Development of cost database?

14 Urban Water Security Research Alliance Acknowledgements Lavanya Susarla, Moreton Bay Regional Council Nicole Ramilo, BMT-WBM THANK YOU!

15 Greenhouse gas emissions BACKGROUND UWSRA report Hall, M. R., J. West, et al. (2011). "Long-Term Trends and Opportunities for Managing Regional Water Supply and Wastewater Greenhouse Gas Emissions." Environmental Science & Technology 45(12):