Transcript Vision 2020
Vision 2030 – Water, sanitation and climate change: Policy implications Dr Guy Howard, DFID Dr Jamie Bartram, University of North Carolina at Chapel Hill Introduction Water and sanitation provision in the future must be resilient to climate change But: What factors contribute to the vulnerability of W&S technologies to climate change? What adaptations can be made to W&S to increase resilience to climate change? What are the policy implications? DfID-WHO Vision 2030 study DFID and WHO jointly commissioned study into watsan technology resilience to climate change Decadal forecasts for rainfall 2020 and 2030 by Hadley Centre (average and heavy 5-day events) Review of technology resilience by Uni Surrey Forward projections of coverage (total, urban, rural, and by technology) Example map: Annual average rainfall 2020 Water supply and sanitation 2020 Data collected for the 2008 JMP report disaggregated into individual improved technologies. Rural and urban coverage calculated Projections made to 2020 for rural and urban coverage. Projections for each technology normalised to ensure overall coverage did not exceed 100%. Projections represented graphically. Water supply coverage 2020 Sanitation coverage 2020 Insert image Climate resilience of watsan technologies Three methods used to assess the resilience of technologies to climate change: Literature review Interviews with W&S experts Questionnaire survey Results expressed as a series of vulnerability matrices Potential impact of climate change on sustainability of sanitation Potential impact of climate change on sustainability of water supply Policy implications Utilities more resilient because of strong potential adaptive capacity Only small number of technologies likely to have global application in future – others only regional or local - JMP criteria will need to change At-house water supply desirable – but not necessarily through piped water Policy implications cont'd WSPs provide framework for supporting adaptation - Risk-based approach covering source to cup But will need to develop scenario-based planning Need improved water resources management to support resilience Resilience – major findings All technologies have some potential resilience Actual resilience depends on local conditions and management Larger utility systems higher potential resilience than small towns and community management Resilience of water supply technologies Technology Resilience Issues Tubewells High Motorised pumping may pose challenge in drying environments Dug wells Low Problems with water quality and securing year-round supply already problematic Protected springs Low-medium Water quality threats from increased rainfall and reduced flow in drying environments Household roof rainwater Low Reduced frequency but more intense rain and drying environments pose threats Treatment processes Medium Processes are resilient, but management systems will determine actual resilience Piped water High inherent vulnerability, impact can be reduced with effective management Low Resilience of sanitation technologies Technology Resilience Issues Pit latrines High Many adaptations possible, but flooding will represent a particular challenge Septic tanks Low-medium Vulnerable to flooding and drying environments Modified sewerage Medium Less vulnerable than conventional sewerage to reduced water quantity, but flooding a threat Conventional sewerage Low-medium Risk from reduced water availability and flooding of combined sewers Sewage treatment Low-medium Treatment requirements may increase as carrying capacity reduces Policy issues: Centralise or decentralise? Decentralisation will hedge drought and floods risks BUT, management decentralisation has poor record of sustainability More frequent flooding increases importance of avoiding critical points Need to (re-)consider greater centralised management support Higher service levels and climate change Post 2015 targets need greater ambition! At-house piped water supply Unclear how many such supplies be delivered via piped systems Are alternatives (self-supply) viable? Monitoring needs to change Category Technologies/approach Potentially resilience to all expected climate changes Utility piped water supply (including treatment systems) Tubewells Pit latrines Low-flush septic systems Potentially resilience to most climate changes Protected springs Community-managed piped supplies High-volume septic systems Conventional and unconventional sewers Potentially resilience to restricted climate changes Rainwater harvesting Dug wells Key Conclusions 1. Need climate-smart policy and planning 2. Need to translate potential resilience into actual resilience 3. Despite uncertainty, sufficient knowledge for policy and planning in most regions 4. Need to resolve key knowledge gaps 5. Adapting to climate change may provide opportunities to improve sector delivery Vision 2030 – Water, sanitation and climate change: Policy implications Dr Guy Howard, DFID Dr Jamie Bartram, University of North Carolina at Chapel Hill