1. Rainwater Harvesting (RWH) Project EPPC: Climate Change Information and Research Date: 12 August 2016 1

2. Overview of the presentation Water and Changing Climate Climate Change Projections in Gauteng Rainwater harvesting-advantages and disadvantages Alignment with the National Priorities Where to from here 2

3. Water and Changing Climate Climate change impacts in South Africa are likely to be felt primarily via effects on water resources. Projected impacts are due to changes in rainfall and evaporation rate. Development options will likely be influenced by the opportunities and constraints that arise from climate change impacts on the water sector. 3

4. Water and Changing Climate To build resilience to climate change in the water sector, resource planners need to ensure: - Policy review for enabling flexible frameworks; - Flexible and robust infrastructure planning; - Maintaining and rebuilding ecological infrastructure in vulnerable systems; - Institutional oversight to ensure that water- related institutions build adaptive management capacity; and - Sustainable and locally accessible financial management. 4

5. Climate Change Projections in Gauteng (GCCRS,2011) Mean Annual Temperature is projected to be 2 to 3°C by 2050s and 3 to 6°C by 2090s. Rate of change of Gauteng temperature per decade is expected to be 0.25 to 0.5°C by 2050s and 0.5 to 1°C by 2090s. Evaporation from dams and soil in Gauteng is expected to increase by 5% to 10% in the 2050s and by 15% to 25% in the 2090s. 5

6. Climate Change Projections in Gauteng Region is however expected to have 0 to 40% increase in rainfall by 2050s and 20% to more than 60% increase in some parts by the 2090s; Increase in rainfall intensity and the resulting flash floods is already being experienced in the region. Given these projections, promoting roof top RWH technology giving special attention to effectiveness of the RWH system is an implementation of adaptation strategy 6

7. RWH Rainwater tank has three basic elements: roof top (catchment area), gutters (conveyance system) and storage tank, while RWH could be more complex system RW collected can be used for variety of applications which include: toilet flushing, washing, drinking for animals and gardening 7

8. RWH When treated properly, can be used for drinking as well The concept of harvesting rainwater in the event of scarcity is not entirely new idea Common use the rainwater harvesting for household gardens Can be used in communal space, such as landscaping for around clinics, commercial buildings, malls, parking areas, etc. 8

9. RWH Advantages Easy to maintain (mosquitoes can easily be managed if proper screens are installed) Reducing water bills Managing stormwater at source helps mitigate the negative impacts of urbanisation on water quality and flow Reduces floods and soil erosion Making use of a valuable resource that is FREE 9

10. In ground RWH 10

11. Rainwater tanks 11

12. RWH continue Disadvantages Regular maintenance Roof materials may leach toxins. Anaerobic conditions can develop in RWH storage tanks where the stormwater has high levels of organic matter and the residence time is long can lead to odour problems. Initial high costs Relatively expensive means of harvesting and reusing stormwater. Storage limits 12

13. Alignment with national priorities The National Climate Change Response Policy specifically states “poor storm water drainage systems and urban induced soil erosion result in flash flooding. Increased storm intensity due to climate change exacerbates such problems”. 13

14. Alignment with national priorities Furthermore, the Gauteng Climate Change Response Policy, (GDARD 2011) specifies that “all new urban developments of communal and private infrastructure are required to incorporate elements of storm water infiltration rather than channeling it as run- off into storm water drains”. It also states “Requirements for rainwater harvesting from buildings are part of building codes for new construction.” 14

15. Where to from here? The proposed project has three phases: Phase 1- 2016-17 Collect data and analyse existing rainwater systems in the province in terms of effectiveness of water collection, water use and simplistic Cost-Benefit Analysis. The data to be collected in urban and rural areas, government and donor projects as well as private sector. The data from Green Building Council will also be used. The data will be entered into a database including spatial details for further analysis Support and review by the GCRO, DWS and WRC through Steering Committee (possible partnership with municipality) Develop criteria for RWH selection for different application types (school, community project in rural area and townships, small holdings, dense urban areas, landscaping around clinics, etc.) 15

16. Phase 2- 2017-18 Select location and RWH types for 400 different intervention projects (tanks and more complex RWHs) based on results of Phase 1 and inputs from Steering Committee Identify and capacitate the NGOs/CBOs to train communities in installation of tanks and RWHs Procure and oversee installation of tanks and RWHs Set up reporting system to monitor RWH effectiveness 16

17. Phase 3- 2018-19 Monitor and evaluate effectiveness of Phase 2 projects. Promote and support manufacturing of the low cost tanks and RWHs in Gauteng Awareness building on benefits of rainwater harvesting Annual reporting and analysis of impacts of the existing and newly build systems For better analysis of impacts need to keep reporting for at least 3 years 17

18. For more information Rina Taviv CCIR 011 240 3177 Ndivhudza Nengovhela CCIR 011 240 3399 18

19. Questions Thank you 19