1 4 Demographic Change Is urban isation a
1. 4 Demographic Change Is urban isation a solution or a prob for impro lem ving san itation? 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 (%) % LA & C = Latin America and the Caribbean Source: UNDP & Unicef, 2003
City council capacity to do its part % Proportion of wastewater being effectively treated Treated wastewater Source: UNDP & Unicef, 2003
Evolution of the relationship between residents and utilities in Sweden subscriber 1970 customer partner 1990 Time Supply of water All want to connect H 2 Olaw All water can be cleaned Price Envir. law Demand Simple treatment plants ety i c o cal s mi e h C Jan-Olof Drangert, Linköping University, Sweden Cannot treat all water at acceptable cost
Demographic patterns are decisive: The growth-infrastructure hypotheses Population 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
Example 2: Evolution of w&s in Norrköping, Sweden Norrköping (thousands) Town area expansion First piped water Source: Drangert & Hallström, 2002
Hypotheses on best management option Population transition proportions Time Turn-key own-key Jan-Olof Drangert, Linköping University, Sweden
Economic development and W&S in Cranfield, UK National GDP person real with 0. 88% and 2. 15% per year trend lines 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
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 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
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