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1.4 Demographic Change Learning objectives: to gain insights about the role of demography in sanitation planning and implementation Jan-Olof Drangert, Linköping University, Sweden The Urban Sanitation Challenge World population (in billions): 2000 2050 (estimate) Total 6 9.3 Rural 3 3 Urban 3 6 Thus, new housing on virgin land in new cities provides excellent opportunities for new sanitation options to fulfil the Millennium Development Goals for sanitation Jan-Olof Drangert, Linköping University, Sweden Population growth rates and the proportion living in informal settlements: means for the largest cities (%) % 30 25 20 Informal settlements Population growth/year 15 10 5 LA & C = Latin America and the Caribbean 0 Africa Asia LA & C Oceania Europe Source: UNDP & Unicef, 2003 City council capacity to do its part % Proportion of wastewater being effectively treated 90 80 70 Treated wastewater 60 50 40 30 20 10 0 Africa Asia LA & C America Europe Source: UNDP & Unicef, 2003 Evolution of the relationship between residents and utilities in Sweden subscriber 1970 customer 1990 partner Time Supply of water All want to connect H2Olaw All water can be cleaned Simple treatment plants Jan-Olof Drangert, Linköping University, Sweden Price Demand Envir. law Cannot treat all water at acceptable cost Demographic patterns are decisive: The growth-infrastructure hypotheses Population transition transition Time Slow development of the infrastructure Lowering portion or even absolute decrease of infrastructure Rapid improvement Jan-Olof Drangert, Linköping University, Sweden How to manage sanitation arrangements? A key question is about control, not degree of centralisation. Two extremes: 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 WC & sewerage Septic tank Turn-key Dry urinediverting toilet Own-key Aqua privy Dug latrine Jan-Olof Drangert. Linköping University, Sweden Example 1: Evolution of w&s in Kisumu town, Kenya Population 350,000 300,000 200,000 100,000 Independence 50,000 1900 Ownkey Turn-key 1950 1963 2000 Source: Drangert et al., 2002 Norrköping (in Example 2: Evolution thousands) of w&s in Norrköping, Sweden Norrköping 140 (thousands) Town area expansion 120 Town area expansion 100 80 p ip e d w a t e r Town area expansion s e w e ra g e wc N o rrk ö p in g 60 First piped water 40 20 00 20 90 19 80 19 70 19 60 19 50 19 40 19 30 19 20 19 10 19 00 19 90 18 80 18 70 18 60 18 18 50 0 Source: Drangert & Hallström, 2002 Hypotheses on best management option Population transition transition proportions Time Turn-key own-key Turn-key own-key Turn-key own-key Jan-Olof Drangert, Linköping University, Sweden Economicdevelopment Development and Water Supply in ain ' Secondary city' UK Economic and W&S Cranfield, National GDP per person real with 0.88% and 2.15% per year trend lines National GDP per person real with 0.88% and 2.15% per year trend lines $40,000 $35,000 $30,000 $25,000 $20,000 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 High-inc $15,000 Present upper $10,000 middle-income Household toilets generally achieved Present lower middle-income $5,000 Present low-income economies average GNI pc at PPP 'Cost reflective tariffs' required for newly privatised providers (300 year sewer replacement cycle?) Source: Cranfield university, UK 20 00 19 75 19 50 19 25 19 00 18 75 18 50 18 25 18 00 $0 Evolution of indoor water taps in rural Sweden 10 Mil 90% 100% BUT, what about the impact of urbanisation? 63% 5 Mil 50% 70% 29% 17% 10% 1900 1950 2000 Gradual improvement towards full coverage Jan-Olof Drangert, Linköping University, Sweden 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 However: We still act as if we were a few hundred million people on earth! Jan-Olof Drangert, Linköping University, Sweden