Sanitation Options for Sustainable Housing A Decision Making Tool Jeremy Gibberd

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1 Sanitation Options for Sustainable Housing A Decision Making Tool Jeremy Gibberd

2 Format The current situation Settlement characteristics in terms of sanitation Sanitation types Sanitation Options for Sustainable Housing (SOSH) Application of the SOSH Conclusions

3 Housing, water and sanitation backlogs Housing backlogs 1994:1.5 million, 2011: 1.9 million, 2017: 2.3 million 13.7% of the population living in informal dwellings 1,755,000 households (3% population) did not have access to a water supply 17% had substandard sanitation (Statistics South Africa, 2018).

4 Water systems maintenance Municipal infrastructure Status of waste water treatment facilities 2014: 26% Critical, 31% High Risk, 26% Moderate, 16% Low Risk (Green Drop report, 2014) Reliability of supply : 50% Limpopo, Mpumalanga households reported interruptions of greater than 2 days Rapid increases in water outages in North West, gradual increase nationally Green Drop report

5 Water resource shortages Availability and cost of water 30% of South African towns are in water deficit Shortages expected in another 13% of towns within the next five years A further 12% in the next five to ten years (National Water Resource Strategy). Water tariffs increases ie 50% increase in Cape Town between 2016 to

6 Sanitation and health Cholera outbreaks and diarrheal disease linked to poor sanitation 15% of children s death in low and middle income countries are due to diarrheal disease. 9.3% of deaths of 5-year-olds attributed water, sanitation and hygiene in South Africa Cholera outbreaks: Zimbabwe (September 2018), the Congo (March 2018), Mozambique (February 2018), Tanzania (January 2018) (WHO, 2018).

7 Climate change impacts Climate change Higher temperatures will intensify water demands ( Longer dry spells and droughts will increase the possibility of water shortages and outages Storms and associated flooding are likely to affect water supply systems and affect water quality Patterns different across the country a differentiated approach is required Englebrecht, 2017

8 Climate change impacts Settlement characteristics and sanitation Permanence Density Water supply Availability of organic material Groundwater and flooding Cultural and social mores Municipal and local management capacity to develop and manage sanitation systems Capital for sanitation systems Ongoing funding for operation of sanitation system Englebrecht, 2017

9 Climate change impacts Sanitation types Flush with main sewage Flush with septic tanks Flush with conservancy tanks Neighbourhood bio filtration systems Pour flush Aqua privy Ventilated pit latrine Composting with offsite disposal Composting with onsite disposal

10 Flush toilet with mains sewage Systems cannot work without water Cost of water increasing (50% increase in Cape Town ) Mains sewage Water supply

11 Flush toilet with onsite septic tanks Periodic removal of sludge System cannot work without water Requires on space onsite Can be connected to field drains Onsite septic tank linked to field drain Water supply

12 Flush toilet with onsite conservancy tank Tank pumped when full Systems cannot work without water Significant costs associated with pumping conservancy tanks Onsite conservancy tanks Water supply

13 Flush toilet with neighbourhood biological Wastewater treatment plant Significant capital costs Maintenance capacity Local supply of treated water Treated water available for use Biological wastewater treatment plant Water supply

14 Aquaprivy Low water requirements Can be used indoors Access for occasional removal of solids Septic tank or conservancy tank

15 Pour Flush Used in Asia Not well know locally Septic tank or conservancy tank

16 Ventilated Pit Latrine Widely use in rural areas Potential for contaminating groundwater (if pit is not lined) Solid material removed occasionally or toilet moved

17 Composting toilet with offsite disposal Used in Germany, USA, Sweden, Haiti SOIL in Haiti produces compost that is sold as fertiliser Composting container

18 Composting toilet with onsite disposal Requires space onsite Produces compost that can be used in landscaping Composted material removed when full Composting container

19 Sanitation Options for Sustainable Housing (SOSH) Settlement characteristics Permanence Density Water supply Flooding Capital costs Ongoing costs Sanitation types Flush system Bio filtration Conservancy systems Aqua privy VIP Composting

20 Sanitation Options for Sustainable Human Settlements (SOSH)

21 Settlement Flush toilet and mains sewage Flush toilet and onsite septic tanks Flush toilet with conservancy tank Flush toilet and neighborhood plant Aqua privy and onsite septic tank Pour flush and onsite septic tank Ventilated pit latrine Composting toilet with offisite disposal Composting toilet with onsite disposal Temporary informal settlement Permanence Portability and reuseability of sanitation Not permanent Sanitation can be moved and reused May be permanent in the future Sanitation can be moved and reused with difficulty Is permanent Sanitation is not portable or reuseable Density of human settlement Onsite space requirements of sanitation Settlement has housing with yards Sanitation requires external space locally Settlement has housing with small yards Sanitation requires space under latrine Dense urban settlement with no yards Sanitation does not require any additional space Water availability Water requirements No water available on site Suitable for use in area with no water Very limited water available on site Suitable for use in area with very little water Piped water available on site Suitable for use in area with plentiful supply of water Organic material availability Organic material No organic matter available Sanitation requires organic material on site Organic material available nearby Sanitation requires organic material nearby Organic material available on site Sanitation does not require organic material Groundwater and flooding Potential for polluting groundwater High ground level water/flooding likely Can be used in areas with flooding / high water table Hig ground level water/flooding possible Can be used where there is a high water table High levely ground water/flooding will not occur Can be used in areas with no flooding / high water table Culture and society Sanitation Highly conservative Likely to be regarded as conservative Partially open to innovation Neither conservative or innovative Welcomes innovation Likely to be regarded as highly innovative Municipal/local management capacity Shared / external responsibility High capacity Can be used where there are high levels of external support Partial capacity Can be used where there is some external support No capacity Can be used where there is no external support Capital available for sanitation Capital cost Very little capital available for construction Can be constructed with very little capital Some capital available for construction Can be constructed with medium capital costs Capital available for construction Can be constructed with high capital costs Funding available for operational costs Ongoing costs Very little funding for operation Can be operated with very low running costs Some funding available for operation Can be operated with medium running costs Funding for operation Can be operated within high operational budgets Alignment Settlement Informal settlement, on the periphery of a town, newly established, medium density, limited funding Alignment: Composting toilets

22 Settlement Flush toilet and mains sewage Flush toilet and onsite septic tanks Flush toilet with conservancy tank Flush toilet and neighborhood plant Aqua privy and onsite septic tank Pour flush and onsite septic tank Ventilated pit latrine Composting toilet with offisite disposal Composting toilet with onsite disposal Student housing on campus Permanence Portability and reuseability of sanitation Not permanent Sanitation can be moved and reused May be permanent in the future Sanitation can be moved and reused with difficulty Is permanent Sanitation is not portable or reuseable Density of human settlement Onsite space requirements of sanitation Settlement has housing with yards Sanitation requires external space locally Settlement has housing with small yards Sanitation requires space under latrine Dense urban settlement with no yards Sanitation does not require any additional space Water availability Water requirements No water available on site Suitable for use in area with no water Very limited water available on site Suitable for use in area with very little water Piped water available on site Suitable for use in area with plentiful supply of water Organic material availability Organic material No organic matter available Sanitation requires organic material on site Organic material available nearby Sanitation requires organic material nearby Organic material available on site Sanitation does not require organic material Groundwater and flooding Potential for polluting groundwater High ground level water/flooding likely Can be used in areas with flooding / high water table Hig ground level water/flooding possible Can be used where there is a high water table High levely ground water/flooding will not occur Can be used in areas with no flooding / high water table Culture and society Sanitation Highly conservative Likely to be regarded as conservative Partially open to innovation Neither conservative or innovative Welcomes innovation Likely to be regarded as highly innovative Municipal/local management capacity Shared / external responsibility High capacity Can be used where there are high levels of external support Partial capacity Can be used where there is some external support No capacity Can be used where there is no external support Capital available for sanitation Capital cost Very little capital available for construction Can be constructed with very little capital Some capital available for construction Can be constructed with medium capital costs Capital available for construction Can be constructed with high capital costs Funding available for operational costs Ongoing costs Very little funding for operation Can be operated with very low running costs Some funding available for operation Can be operated with medium running costs Funding for operation Can be operated within high operational budgets Alignment Settlement Student housing, in centre of town, campus site, medium density, limited funding Alignment: Neighbourhood bio filtration

23 Climate change impacts Conclusions Flush toilet and pit latrine based sanitation appear increasingly vulnerable under climate change and urbanisation (water scarcity, irregular supply, flooding, increasing densities, reduced food security, biodiversity loss) Sanitation Options for Sustainable Human Settlements methodology: Supports a re-evaluation of flush toilets and pit latrine sanitation. Enables basic assessments of settlements in terms of characteristics such as permanence, flooding, water availability, costs, and social and cultural mores, as a prerequisite for the selection of sanitation. Advocates an evaluation of local sanitation development and management capacity. Encourages consideration of alternative sanitation systems that do not use water, treat wastewater locally and provide valuable fertiliser.

24 Climate change impacts Thank you, Questions? Jeremy Gibberd,