Are nutrients the issue here?

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1 Non-traditional technologies - Recovery of resources Disclaimer: This presentation does not necessarily reflect official U.S. EPA policy Office of Research and Development National Exposure Research Laboratory 1 Are nutrients the issue here? No it is all about the money So for technology options it is all about resource recovery (energy, nutrients, H 2 O) People need to save money & have water services well into the future Waste of energy in the water sector Water services utilize about 3-7% of electricity produced i.e. some 100 billion kwh/y = 16 avg coal power plants Yet there is about the same amount of embedded energy in food/fecal residuals in our sewers However household energy use 14% for hot water i.e. heating water more important energy issue 3 rd highest use after heating (29%) & cooling (17%) of homes Let s rethink the municipal water system First noting how we got to where we are today Second based on a system s view what could be more sustainable And do we have the wrong economic & service model? Given $20 billion/y annual short-fall in water system maintenance (EPA GAP report, 2005) Most significant incentive for waterworks was fire fighting Next was disease concern Etiologic agents (%) for 780 drinking water outbreaks, USA 4 Since the Great Fire of London in 1666 the market for fire insurance was opened up US National Board of Fire Underwriters 1872 lead to premiums reduced 20-50% if waterworks available for fire fighting Drinking water system still designed today based on providing fire fighting flow Hence lose of quality and excess to private needs! Silsby first steam Fire Pump Engines, , USA (30% Cu, 12% F, 9% NO 3- ) 5 (85% Norovirus) Craun et al. (2010) CMR 23: (29% since % of deaths) (Some likely to be viral & parasitic protozoa, but how many are nonculturable bacteria?) (403,000 cases from a single outbreak of Cryptosporidium hominis in Milwaukee (WI) April 1993, but only 9% of outbreaks vs. Giardia 86%)

2 Water futures energy limited by the current design Energy used (kwh) Novotny (2011) Wat Sci Technol 63(1): Reuse limit i.e. need to change the system Renewable energy Demand manag t was the first step Sydney s water savings Same usage today as in 1972 Dual systems mandated in all greenfield developments But the next million pop? 6 0.Percent water demand reduction Water conservation only Water conservation & stormwater reuse Water conservation & wastewater RO reuse Sydney Water Corp, Prosser (2011) Water: Science and Solutions for Australia, CSIRO Publishing, Canberra Energy use: rainwater, desal in Australia Need for phosphorus recycling Global phosphate use in agriculture: i.e. need to manage pump type/usage Guano Human excreta Rock phosphate manure 8 9 Year Ashley et al. (2011) Chemosphere 84: World Phosphate Reserves Geopolitically Sensitive More concentrated than OPEC 10 Image courtesy Ostara USA 2% ROW 17% China 6% Morocco 77% 11 Likely trends / Implications Climate change / climate resilient infrastructure: More intense storms, sewer overflows, outages Pressure sewers, off grid systems more resilient Aging population, more prone to diseases e.g. legionellosis via water aerosols (etc.) Need to reduce greenhouse gases: Move less water over long distances, i.e. recycle, especially reuse within homes/buildings Renewable energy & nutrient recovery: Utilize energy within wastes energy/heat recovery Urban agriculture / recycle of local nutrients

3 Current single use 12 We need a paradigm shift Resource recycle instead of disposal 13 Solutions Use of specific process-oriented tools to aid in sustainability assessments, and Product-oriented decision support systems to aid stakeholder involvement in the process Swedish-Australian Urban water sustainability framework Multi-Criteria Decision Aiding (MCDA), using process tools & being stakeholder-driven: Health Impact Assessment Life-Cycle Assessment, EF BCA, Life-Cycle Costing Reliability/ robustness Examples of Urban Master planning Stockholm city brownfield redevelopments Gold Coast, S th of Brisbane, Australia (greenfield development) Common points Not about one issue, but the whole system Dominant driver economic viability 14 Lundie, S., Ashbolt, N., Peters, G., Livingston, D., Lai, E., Kärrman, E., Blaikie, J. and Anderson, J. (2008) Sustainability Framework. WSAA Occasional Paper No.17. Water Services Association of Australia, Melbourne. 15 Hammarby Sjöstad, Stockholm Stockholm Royal Seaport (SRS) (Norra Djurgårdsstaden) This urban development for 10,000 new residences and 30,000 new workspaces, based on Hammarby Sjöstad Planning work started in the early 2000s and the new city district will be fully developed around 2025 Goals: By 2020, carbon emissions <1.5 tonnes/person.year By 2030, free of fossil fuels Resilient to future climate changes 16 17

4 18 19 Pimpama Coomera Water Futures Project Initial 10 Options down to 5 then 1 20 First discussed at a series of strategic workshops attended by Gold Coast Water and key government stakeholders in mid month stakeholderdriven process Innovative water systems Based on sustainability principles interfaced to financing models, food production & healthy living environment An example new water system paradigm No-DW firefighting, blackwater-only sewer, local greywater reuse for nonpotable household use 23 e.g. EcoSan toilet: in India with unique pay-the-user Located in Musiri, Trichy, Tamilnadu, India, the Ecosan Community Compost Toilet Operating since Jan, 2008 Users paid 10 paise per visit - about 1/4 of one US cent as human urine and feces are a valuable source of nutrients used in agriculture (Text and image courtesy of SCOPE) Society for Community Organisation and Peoples Education

5 Future municipal water services: What are the new businesses? For stand-alone homes Small-scale conventional system ystems Primary out Poor maintenance is a major problem 24 Ashbolt, N.J. (2011). In: Energy and Water Water Environment Foundation, July 31-August 3, 2011, Hyatt Regency McCormick Place, Chicago, Illinois, pp Aerated Wastewater Treatment Systems (AWTS) Septic tank Absorption trench Problems with AWTS Require a maintenance contract for use 26 Warranties: Concrete Tanks & Partitions Internal Pipework Electrical control box & alarm panel Pumps 15 years 10 years 5 years 2 years 27 Waterless composting toilets Slow evolution vs step change Sewage treatment (Biolytix NZ system) Vacuum toilet Stand alone single unit for 4 person house e.g. Biolet 60 XL ( 28 Split Level system with ceramic pedestal With or without urine-diversion 29 Urine-diversion Graywater treatment dehydrating toilet Urine-diversion dual-flush toilet

6 Why divert the urine? Urine-diverting toilets WM-Ekologen model DS Other models have combine vacuum system or dry fecal collection with urine diversion. BB Innovation & Co. model Dubbletten gives g N / L Use as a plant fertilizer 30 Normal nitrogen application ( kg/ha) tonnes of urine/ha is needed 31 What s in the pipeline to Urine storage tank (264 gal) & Aquatron solids separator composter reduce demand: 40 to 13 gal/p.d Slone FLUSHMATE Pressure-Assist toilet (1 gal) The PropellairTM toilet (0.4 gal flush) The Propel air flushing system reduces water consumption to 0.4 gal per flush, using 84% less water & 80% less energy than avg 2.4 gal WC The QuenchTM recirculating shower system The commercially available Quench conservation shower uses up to 67% (25 vs 43 L) less water than a low flow shower head & use up to 87% less energy The XerosTM cloths washer Conclusions In addressing the three pillars of sustainability 34 assessments need to consider over the life-time of the complete water services system Human health (chemical, microbial & wellbeing) Environment (water footprint, EF & LCA options) Economic (BCA, NPV, LCC) Probably requires novel market approaches & governance structures to succeed E.g. Maintenance contracts & overarching planning group 35 uses 90% less water & 2% energy since clothes nearly dry, no dryer required