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Ch. 1. Sustainable sanitation - a review Management & organisation Residents´ views & actions Physical arrangements including technology The challenge is to protect our health and the environment This challenge can be addressed, if management, residents, policies, technology and engagement are in place Jan-Olof Drangert, Linköping University, Sweden
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1.1 Sanitary Conditions in the World How do we perceive sanitary conditions? What functions must a sustainable system fulfil? Learning objective: t o become familiar with various sanitary conditions in the world, functions of sanitation, and to foster a critical understanding of statistics and other data. Jan-Olof Drangert, Linköping University, Sweden
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Sanitation – ’the silent crises’ 2.5 billion people (35% of the world's population 2010) lack so called improved sanitation 18% of the world's population lack safe water supply 10% of all wastewater in developing countries is treated Malnutrition is a major factor making us more vulnerable to disease and death, thus food security is important The combined effects of poor personal and domestic hygiene and lack of safe water and good environmental sanitation is considered the most important risk factor for disease and death Jan-Olof Drangert, Linköping University, Sweden
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Proportion of households in major cities connected to piped water and sewers House or yard Connected to connection for water (%) a sewer (%) Africa 4318 Asia7745 Latin America &7735 Caribbean Oceania7315 Europe9682 North America 10096 Source: Stockholm Water Front, No. 4 December 2007
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new Wastewater - collected and treated by effective treatment plants (median percentage) Source: UNDP & UNICEF 2003 (Fig. 3.13 )
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Stormwater, solid and organic waste Animals scavenging organic material and clogged storm water drains Stormwater drainage as a conduit for solid waste Copyright: Jan-Olof Drangert Jan-Olof Drangert, Linköping University, Sweden
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Exercise: Upgrading environmental sanitation in dense settlements Thor-Axel Stenström, SMI, Sweden before after Thor-Axel Stenström, SMI, Sweden What Next?
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Sanitation ladder....... upgrading Outside house: Private dry urine- diverting toilet Communal flush Indoors: Jan-Olof Drangert, Linköping University, Sweden Open defecation Björn Vinnerås Swedish University of Agricultural Sciences Jan-Olof Drangert, Linköping University, Sweden
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Diseases related to excreta and wastewater Disease:Mortality (death/year) Burden of disease* Comments Diarrhoea 1 800 000 62 000 000 99.8% of deaths occur in dev. countries; 90% are children Typhoid 600 000 no data Estimate: 16 million cases/year Ascariasis 3 000 1 800 000 Estimate: 1.45 billion infections, of which 350 million suffer adverse health effects Hookworm disease 3 000 60 000 Estimate: 1.3 billion infections of which 150 million suffer adverse health effects Schisto- somiasis 15 000 1 700 000 Found in 74 countries, 200 million estimated infected, 20 mi with severe consequences Hepatitis A no data Estimate: 1.4 million cases/yr. Source: WHO, 2006 * DALYs/year estimates the time lost due to disability or death from a disease compared with long life free of that disease (See Ch 3).
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Source: UNICEF and World Health Organization, 2012 Sanitation coverage trends by developing region, and urban-rural divide 1990-2010 Urban – rural divide
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Improved urban sanitation coverage 2010 Source: UNICEF and World Health Organization, 2012 Proportion of the population in 59 developing countries using both improved drinking water sources and improved sanitation (per cent)
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What sanitation is about Personal and household hygiene Clean environment incl. water Solid waste management Greywater disposal and treatment Safe excreta disposal Stormwater handling Traditional interpretation: Acceptance, affordable, convenience and pride Environmentally sustainable arrangements incl. chemical risks and resource conservation Additional perspectives : Jan-Olof Drangert, Linköping University, Sweden
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1 2 3 4 5 6 7 Pathogen & hazardous waste reduction – indicators depend on flow-stream Nutrient reuse – (i) X% of excreted N, P, K is reused for crop production, (ii) Y% of used water is reused Nutrient & hazardous waste containment – indicators depend on flow-stream Integrated resource management – indicators depend on flow-stream Access – (i) 24-hr access to facility year-round, (ii) privacy, personal security and shelter, (iii) no smell, (iv) preferrably indoors and accessible to men, women, children, elderly Greywater management – (i) no stagnant water in compound or in streets, (ii) no vectors, (iii) no avoidable pollution e.g. fat or paint residues A sanitation ladder for improved functions Adapted from Kvarnström et al., 2010 Excreta containment – (i) in use, (ii) no vectors, (iii) no faecal matter, (iv) hand-washing facility in use (v) can withstand stormwater events
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Sustainable - more than a catch word The Bruntland Commission (1987) expressed sustainability as: “…development that meets the needs of the present without compromising the ability of future generations to meet their own needs" … Sustainability comprises a variety of perspectives: Ecology, Economy, Social, Resource saving, Reuse, etc. Sustainability criteria for sanitation arrangements may read (EcoSanRes): - protecting and promoting human health, - not contributing to environmental degradation or depletion of the resource base, - being technically and institutionally appropriate, economically viable and socially acceptable Jan-Olof Drangert, Linköping University, Sweden
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Crucial physical boundaries for human activities Biodiversity loss Acid oceans Ozone depletion N & P cycles Land use changes Chemical pollution Source: Rockström et al., 2009 Freshwater global use Aerosol loading Climate change Planetary boundary
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The planet is resilient - but humans can push it over a threshold Resilient to human actions Pushed over threshold New equilibrium and new disturbances Source: Rockström et al., 2009 The globe always remains, but people may perish!
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Requirements on sanitation arrangements Inside the home (old requirements): - hygienic and protecting human health - comfortable (indoors, no smell, easy to clean, security) Outside of the home requirements (new! ): - save resources (little/no water, reuse nutrients, little energy) - protect the environment (ground & surface water, soil, air) Lessons to consider: Requirements change over time, sometimes quickly Energy use is high for conveyance over long distances and for advanced treatment technology Jan-Olof Drangert, Linköping University, Sweden
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Mexico City now has 20+ million people MC Latest opened water source 100 km 1 km Next? 200 km 2 km Jan-Olof Drangert, Linköping University, Sweden Courtesy of Ian Adler, International Renewable Resources Institute, Mexico Saving water at your home
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Reuse or disposal in the history of sanitation Land area making use of organic waste from the city of Stockholm 1910 Karl Tingsten, 1911 Stock- holm 60km The ”silent highway” man rowing on river Thames Illustration: www.CartoonStock.com.
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Epidemics rather than endemics have shaped our views After John Snow discovered (1854) that cholera can be trans- mitted by contaminated well water, sanitary engineers focussed their interest on organic matter in water as an indicator of faecal contamination. Many rivers with high organic loads were wrongly labelled as hazardous since the origin of the organic matter was not from faeces but from humus! (Hamlin, 1990) Example 2 Sanitary inspectors in Linköping (small town in Sweden) described the sanitary conditions in the workers´ living quarters as deplorable with stagnant storm water and awful smell, and causing ill health (1870s). However, infant mortality in such areas did not differ from that in richer areas with piped water and sewers. Lack of sanitary precaution by all classes was the reason, and not until the general hygiene improved did the death toll figures come down! (Nilsson 1994; Esrey, 1990) Example 1
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Continued Example 3 Water issues have been in focus to the detriment of appreciating good sanitation. Cairncross (1989) and others have reached the conclusion that water quantity is more important to good health than water quality for many diseases. Enough water to clean the hands and body, wash clothes, clean the house, etc. is more important than improved drinking water quality at the margin. Lesson to consider: We need to measure the right parameters to be able to draw useful conclusions. Jan-Olof Drangert, Linköping University, Sweden
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Sanitation viewed as less important People assumed to be uninterested Is less of a public concern, and attracts little public investment in poor urban areas up to now Residents do not perceive that they pay for sanitation by eg poor health Lessons to consider: The Millennium Development Goals deal more with water than sanitation issues, but sanitation is picking up with the new emphasis. Separate planning for sanitation and water leads to installation of piped supply long before proper disposal and treatment of wastewater Jan-Olof Drangert, Linköping University, Sweden Water ”will do the trick” Everyone wants water Water supply is a public concern, and attracts public and private investments Easy to charge for the water - if the supply is regular Sanitation versus Water
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1.2
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1.2 Resources: energy From waste via reuse to sustainability ? Where are the unlimited resources? What might be the problem to access them? Learning objective : to familiarise with a coordinated view on resources, and to understand the context and role of sanitation. Jan-Olof Drangert, Linköping University, Sweden
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Reflections on water and plant nutrients Water molecules cannot be manufactured or destroyed Water is renewable (sun- driven cycle) everywhere Water available in situ (rural, peri-urban) or imported (cities) Energy supplied by humans (rural) or electricity (urban) 70% of global water use is for crop production A balanced diet requires a loan of 1300m 3 /yr p person based on current practice. This is 70 times greater than the basic water need of 50 l per person per day. Phosphorus (P) cannot be manufactured or destroyed P is immobile and mined in only a few countries Food available in situ (rural) or mostly imported (cities) Energy supplied by humans and sun (rural) or fossil (urban) 90% of global rock P extrac- tion is for crop production A balanced diet results in depletion of 22.5 kg/yr of phosphate rock or 3.2 kg/yr of P per person based on current practices, of which 0.5 kg is found in the food. Jan-Olof Drangert, Linköping University, Sweden
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agri- culture households excreta organics food fertilizer Losses on farm choice rain & irrigation water evapo- transpi- ration no choice manure Jan-Olof Drangert, Linköping University, Sweden Input to and output from the food chain loss
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The water cycle – dynamics does the trick ” but, H 2 O is always on the move...” Instant snap shot: Ice caps 2.7% Rivers 0.0002% Lakes 0.007% Oceans 96.5% Clouds 0.001% Groundwater 0.7% Shortage of freshwater ! A dynamic perspective gives a better description: 4 600 years 3 000 years 8 days 16 000 years 280 days Renewable rain gives in 2000 years as much water as is in the oceans!!! Jan-Olof Drangert, Linköping University, Sweden
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Annual renewal and use of fresh water CountryH 2 O m 3 /person/ year km 3 /yr total in country Rivers from/to countries Portion being used Total use per year per person - by house- holds - by indu- stry - by agri- culture Sweden 21 110 176 +4 2 % 479 m 3 36% 55% 9% Holland 680 10 +80 16 % 1 023 m 3 5% 61% 34% Saudi Ara 160 2 0 164 % 255 m 3 45% 8% 47% Lebanon 1 620 5 16 % 271 m 3 11% 4% 85% India 2 170 1 850 +235 18 % 612 m 3 3% 4% 93% Tanzania 2 780 76 0 1 % 36 m 3 21% 5% 74% Kenya 590 15 0 7 % 48 m 3 27% 11% 62% Egypt 30 2 +56 97 % 1 202 m 3 7% 5% 88% USA 9 940 2 478 0 19 % 2 162 m 3 12% 46% 42% Chile 35 530 468 0 4 % 1 625 m 3 6% 5% 89% China 2 470 2 800 0 16 % 462 m 3 6% 7% 87% Source: P. Gleick, 1993
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Global scarcity of plant nutrients - a new driving factor for sanitation Phosphorus is a limited resource, and large untapped reserves will eventually only be found on sea shelves and as anthropogenic depositions in lake sediments. 95% of mined potash goes to the fertiliser industry and has no substitute. Mines exhausted in some 50 years. 60% of mined sulphur goes to fertilizer industry and has no substitute. Mines exhausted in some 20 years. Costly to recover these plant nutrients from lake sediments compared to trapping them directly at the source i.e.as output from households and industries. Nitrogen can be manufactured from the N in the air, but this requires much energy (1 litre of oil to produce 1 kg of nitrogen). D. Cordell & J-O Drangert, Linköping University, Sweden
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Phosphate Rock – Worldwide Estimates (thousands of metric tons) P scarcity is worse than oil scarcity because P CANNOT be substituted in food production Courtesy of Ian Caldwell, Stockholm Envrionment Institute, Sweden
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Food, water and nutrient flows food H2OH2O 1.5 l 1.1 l transpiration & evaporation 0.9 l Urine: 1.5 l Faeces: 0.15 l Jan-Olof Drangert, Linköping University, Sweden + nutrients Virtual water 4 cu.m.
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NUTRIENTS – and demography World Total 16 th - 21 st century Billion people 150016001700180019002000 3 6 2100 Jan-Olof Drangert, Linköping University, Sweden 20 th century 9 rural 21 th century urban
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Actual reuse of nutrients for urban agriculture & food security (in Swedish towns 1850 – 2000) 100% 50% 1870191019502000 waste pits + urine diversion + WC only WC + WWTP stop Jan-Olof Drangert, Linköping University, Sweden Proportion nutrients being reused Glass, tins, ceramics Heavy metals
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Human resources: capacity to manage sanitation arrangements Utility Household Work hoursPaying fees Level of management User contribution pit latrine urine- diverting toilet flush toilet, WWTP, wetland Grease trap, Organic waste septic tank sewerage water supply, biogas drainage Jan-Olof Drangert, Linköping University, Sweden sewerage Organic waste biogas
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”Manpower blindness”: driver of new responsibility sharing We tend to account only for what is done by governments and projects in water and sanitation What is done by residents and small entrepreneurs is rarely appreciated, if at all recognized (blindness) Yet, many urbanites survive thanks to such local initiatives Here, we pledge that both kinds of activities are needed to solve current sanitation problems Our pre-conceived views play a role Jan-Olof Drangert, Linköping University, Sweden
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1.3
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1.3 Resource Flows From where do resources come, and where do they end up? versus Learning objective: to grasp how resource flows are created and manipulated, and to become familiar with methods of analysing resource flows and the challenges they pose. Linear flow Loop Jan-Olof Drangert, Linköping University, Sweden
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Features of present policies and practices – and an anticipated paradigm shift Prime fertile soils converted to town areas Reduced recycling of organic material Less urban agriculture, etc. J-O Drangert, Linköping University, Sweden while we instead need more short loops for substances More linear flows
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What comes in …… Water 20-200 kg/p/day Food 1-2 kg/p/day Energy > 1 kg/p/day Consumer goods 1- ? kg/p/day Jan-Olof Drangert, Linköping University, Sweden house- hold
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… must go out Greywater 20-200 kg/p/day Solid waste 1 - ? kg/d/p Faeces 0.3 kg/d/p Urine 1.5-3 kg/d/p Jan-Olof Drangert, Linköping University, Sweden house- hold pollutants
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The trick is to bend today´s many linear resource flows Solid waste is the most visible output. It may be discarded or sorted and recycled. Scavengers perform an important service Faecal matter is very small in volume, but is a major health threat unless treated and used wisely Urine (urine) volumes are small. Bad odour may be a problem unless urine is returned to the soil Greywater is voluminous and a major challenge in dense areas but can be a useful product if handled well Stormwater may be a serious problem but harvesting it can augment household and irrigation water supplies Energy is invisible but heat may be recovered Jan-Olof Drangert, Linköping University, Sweden
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Water and nutrient ’kretslopp’ Rural home City with linear flows Sorting city food Wastewater = (greywater, urine, and faeces) WWTP Wastewater food chemicals J-O Drangert, Linköping University, Sweden Leaking pipes water
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Three examples of ’kretslopp’ thinking Fraction: Solid ‘waste’ Organic ‘waste’ Faecal matter Urine (urine) Greywater Stormwater In Stockholm sorted in 8 fractions, collected and reused organics composted together with hygien- ised dry faecal material collected and trucked to farm in situ after biological treatment infiltration (no heavy rains) In Kimberley No sorting, collected and put on landfills dried and composted used in situ or by truck to council gardens Greywater to pond after biological treatment, and rainwater to the same pond. Little rain. In Kampala No sorting, burnt in situ, the rest to landfill banana peels etc to animal feed dried and composted in situ or collected Infiltrated in situ and to drains In drains but flooding due to heavy rains Jan-Olof Drangert, Linköping University, Sweden Provides heating/energy Provides soil conditioner Liquid fertiliser Irrigation water and biogas Groundwater recharge Soil conditioner Liquid fertiliser Soil conditioner Liquid fertiliser Soil conditioner
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Where do we go from here? SustainabilitySustainability Interpretation of the ’waste hierarchy’ Solid waste Reuse/recycle Incinerate Liquid waste Sludge Land fill Polluting discharges Reuse/recycle Jan-Olof Drangert, Linköping University, Sweden NEW! Reduce generation and polluting content in goods - protecting & promoting human health, - not contributing to environmental degradation or depletion of resource base, - being technically and institutionally appropriate, economically viable and socially acceptable
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Material Flow Analysis for human settlements MFA uses the principle of mass balance: input = output + accumulated stock in the system and provides a systematic description of the flow of goods, materials or substances through various processes and out of the system. Process 1 Process 2 input Process 3 output Jan-Olof Drangert, Linköping University, Sweden
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A resource flow model for a hamlet 46 Courtesy of Jenny Aragundy, Ecuador
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47 The Stockholm model to improve sustainability Courtesy of Stockholm Water Company
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food hydrosphere waste handling consumption deposit/ landfill livestockagriculture urine faeces Modelling the situation (MFA) Select the material, product or chemical you are interested in Include all the flows, uses, losses and disposals Find estimates for all flows and stocks 4 STEPS in modelling: (1) Description of the system (2) Formulation of model equations, (3) Calibration, and (4) Simulation incl. sensitivity and uncertainty analysis Decide the boundaries of your system (dashed line) Jan-Olof Drangert, Linköping University, Sweden
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Example 1: Actual reuse of nutrients from urban households in agriculture 100% 50% 1870 1910 19502000 waste pits + urine diversion +WC only WC+WWTP stop Jan-Olof Drangert, Linköping University, Sweden Proportion being reused Heavy metals Glass, tins, ceramics
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Ex. 1 cont.: Examples of ranges for parameters Neset and Drangert, 2010
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Ex. 1 con´t Sensitivity analysis The filled curves represent calculated averages, while coloured areas between the dotted curves indicate uncertainty ranges due to estimated input data (in kg phosphorus per capita per year) Source: Neset and Drangert, 2010 Phosphorus reuse and phosphorus losses 1870-2000
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Example 2: Eutrophication of Lake Dianchi, China 55% of TP 45% of TP Kunming city Farmland P leakage river downstream 385 tonnes 33 tonnes Jan-Olof Drangert, Linköping University, Sweden Production Consumption
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Dianchi faeces flush urine flush laundry kitchen bath industrial discharge HH denitrificationstreet runoffroof runoff runoff comb. sewer infiltration incl. river water exfiltration wrong connection storm sewer separate storm water drainage treated wastewater overflow out of CSO tank overflow out of combined sewer WWTP sludge CSO tank Ex. 2 Con't Urban P flow to Dianchi Lake, China Source: Huang et al., 2007
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Ex 2 Con't Outcome to guide a new strategy 1. A major problem is that during heavy rains the wastewater bypasses the WWTP and washes all wastewater straight into the lake. 2. Groundwater and stormwater enter the poor-quality sewers and make up a large portion of the water coming to the WWTP 3. Even with the best available treatment technology (BAT with 98% P removal etc.) the discharge would still be twice what the lake can accommodate. 4. Source-control measures such as urine-diversion toilets and P-free detergents and body care products are required to avoid discharging untreated wastewater downstream the lake and, thus, just moving the environmental problems. Source: adjusted from Huang et al., 2007 Do not mix waste streams Infiltrate rainwater locally Source separate urine
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Example 3 : P flows through Hanoi City Source: Montangero et al., 2004
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Ex. 3 con't Phosphorus flows in Hanoi City Courtesy of Agnes Montangero, 2007 Composting Agriculture Market Sewerage & drainage Landfill Organic waste collection On-site sanitation House- holds Water supply
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Ex. 3 con't : Feeding the people of Hanoi - a sensitivity analysis Source: Montangero et al., 2007 2007 (3 M) Business as usual 2015 (5 M residents) No septic tanks No-meat diet
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Example 4: Nutrients and food security- a simplified global mass balance Source: Clift and Shaw 2011, based on Cordell and others
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Securing a sustainable phosphorus future The future is not all dark! Ex 4 con't
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Principle: Organic ≠ other solid waste Stormwater ≠ sewage Industrial ≠ household wastewater Black toilet water ≠ greywater Faeces ≠ urine Strategies for sanitation improvements Jan-Olof Drangert, Linköping University, Sweden
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1.4
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1.4 Demographic Change Is urbanisation a solution or a problem for improving sanitation? Learning objectives: to gain insights about the role of demography in sanitation planning and implementation Jan-Olof Drangert, Linköping University, Sweden
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The Urban Sanitation Challenge World population (in billions): 2000 2050 (estimate) Total 6 Rural 3 Urban 3 3 6 Jan-Olof Drangert, Linköping University, Sweden Thus, new housing on virgin land in new cities provides excellent opportunities for new sanitation options to fulfil the Millennium Development Goals for sanitation 9.3
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Population growth rates and the proportion living in informal settlements: means for the largest cities (%) % Source: UNDP & Unicef, 2003 LA & C = Latin America and the Caribbean
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Treated waste- water City council capacity to do its part Source: UNDP & Unicef, 2003 % Proportion of wastewater being effectively treated
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Evolution of the relationship between residents and utilities in Sweden 1970 1990 subscriber customer Supply of water All water can be cleaned All want to connect Simple treatment plants H 2 O- law Price Demand Envir. law C h e m i c a l s o c i e t y Cannot treat all water at acceptable cost partner Time Jan-Olof Drangert, Linköping University, Sweden
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Demographic patterns are decisive: The growth-infrastructure hypotheses Population Time transi- tion Slow develop- ment of the infrastructure Lowering portion or even absolute decrease of infrastructure Rapid improvement Jan-Olof Drangert, Linköping University, Sweden
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How to manage sanitation arrangements? Turn-key management where a utility (private or public) provides the service and the residents just pay the bill Own-key management where single households or housing associations initiate, build and control, while they put to use available skills, materials, and other local resources Turn-key Own-key WC & sewerage Dry urine- diverting toilet Dug latrine Aqua privy Jan-Olof Drangert. Linköping University, Sweden A key question is about control, not degree of centralisation. Two extremes: Septic tank
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Example 1 : Evolution of w & s in Kisumu town, Kenya 1963200019501900 Turn-key Own- key Source: Drangert et al., 2002 350,000 200,000 300,000 100,000 50,000 Population Indepen- dence
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Example 2: Evolution of w & s in Norrköping, Sweden Source: Drangert & Hallström, 2002 Norrköping (thousands) First piped water Town area expansion
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Hypotheses on best management option Population transi- tion own-key Jan-Olof Drangert, Linköping University, Sweden proportions Turn-key Time
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Water Closets becoming popular in capital city Newly installed WCs discharging to ditches, Hagley Road Ordure is emptied anywhere at nightfall; The city’s first public wash house opened in Kent Street Mind where you tread, Sir, for the children have been here' One third of city using unimproved pit latrines First sewage farm acquired City trying to convert to bucket latrines as improvement 'One in three artisan families still had to share external toilet with neighbours' 45% households access bucket latrines (1 per 10 HHs) 15% using unimproved pit latrines; Over half houses get WCs - most still outside open 'drainage [in one slum court] is so vile that the air seems positively putrid' 20% lacking a WC Still shared toilets for slums Household toilets generally achieved 'Cost reflective tariffs' required for newly privatised providers (300 year sewer replacement cycle?) Source: Cranfield university, UK Economic development and W&S in Cranfield, UK National GDP per person real with 0.88% and 2.15% per year trend lines
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Evolution of indoor water taps in rural Sweden 19001950 100% 10 Mil 17% 2000 50% 29% 63% 70% 10% 90% Gradual improvement towards full coverage BUT, what about the impact of urbanisation? 5 Mil Jan-Olof Drangert, Linköping University, Sweden
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Why do we often act as if we were only a few hundred million people on earth? Small farmers understand and practise reuse, but urban residents do not Ever more people live in big villages, towns and cities Most farmers have had access to chemical fertilisers this far Change comes with a cost But, there is also a saving; better food security Local experience global understanding Jan-Olof Drangert, Linköping University, Sweden However: We still act as if we were a few hundred million people on earth!
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