Adapting to Climate Change in Urbanizing Watersheds ( ACCUWa )

1. Adapting to Climate Change in Urbanizing Watersheds (ACCUWa) SITUATION IN ARKAVATHY BASIN VeenaSrinivasan Fellow, Ashoka Trust for Research in Ecology and the Environment June 18th 2013

2. Objective: Comparative study of climate change-water vulnerability and adaptation in 2 urbanizing watersheds CAUVERY BASIN KARNATAKA Arkavathy Watershed: Peri-urban Bangalore, 4,250 sq.km TAMIL NADU Noyyal Watershed: Peri-urban Coimbatore, 3510 sq km KERALA River Basin Boundary State Boundary

3. Arkavathy Watershed • Tributary of Cauvery • ~1/3 of Bengaluru, 4 Class II towns Sources of Water • Arkavathy River (almost dry) • Import from Cauvery (limited by Tribunal) • Intensive pumping of groundwater (declining) • Rainwater + wastewater (small)

4. Challenges in developing theoretical framework and methods A. Multiple Stressors B. Multiple scales with missing linkages C. Multiple Concerns

5. A. Multiple Stressors:Traditional Natural Science Framework “Top-Down” View of Water Supply Vulnerability Infrastructure Policies Stressors Shocks Seasonality Rainfall Temperature Livelihood / Domestic Water Security Outcomes Water Supply (Quantity and Quality)

6. A. Multiple Stressors: < -5% Projected Increase in Rainfall 2035 A1B Scenario -5% - 0% 0% - 5% 5% - 10% 10% - 15% Source: BCCI-Karnataka, 2011 Both climate models and station rainfall data suggest slight increasing trend in annual rainfall.

7. A. Multiple Stressors: < -5% Projected Increase in Rainfall 2035 A1B Scenario -5% - 0% Arkavathy Basin 0% - 5% 5% - 10% 10% - 15% Source: BCCI-Karnataka, 2011 Both climate models and station rainfall data suggest slight increasing trend in annual rainfall

8. A. Multiple Stressors: Doddaballapur Annual Rainfall (mm/year) 1500 1000 500 0 1925 1975 1900 1950 2000 Both climate models and station rainfall data suggest slight increasing trend in annual rainfall

9. A. Multiple Stressors: Inflows into TG Halli Reservoir (mcft/year) YET inflows into the TG Halli reservoir, which supplies Bengaluru, exhibit a sharp declining trend. (No new upstream dams either)

10. A. Multiple Stressors:Traditional frameworks inadequate Rainfall Water Supply Clearly the approach of blindly applying historical rainfall-runoff relationships to predict future water supply is not valid.

11. A. Multiple Stressors:Need to account for multiple change drivers

12. A. Multiple Stressors:Need to account for multiple change drivers Hypothesis 1. Increase in evapotranspiration due to temperature increase => decrease in flow.

13. A. Multiple Stressors:Need to account for multiple change drivers Hypothesis 2. Excessive GW Pumping reducing base flow

14. A. Multiple Stressors:Need to account for multiple change drivers Hypothesis 3. Increase in “green water use” via plantations decreasing recharge

15. A. Multiple Stressors:Need to account for multiple change drivers Hypothesis 4. Unplanned urbanization causing water to collect in a “million puddles” and evaporate

16. A. Multiple Stressors:set up rival hypotheses Hypothesis 1: Temperature rise Hypothesis 2: GW Pumping Hypothesis 3: Eucalyptus Plantations Hypothesis 4: “Million Puddle Theory”

17. H Livelihood / Domestic Water Security Outcomes N S Household Individual influence P F B. Multiple Scales – Missing LinkagesClimate variability occurs at the basin scale, whereas vulnerability is experienced at the household scale. Social Scientists “Bottom-up” View of Water Supply Vulnerability Vulnerability Context Shocks Seasonality Trends Policies Institutions Processes Source: DFID’s Sustainable Livelihoods Framework

18. B. Multiple Scales – Missing Linkages Institutions No transparency on how water is allocated both within towns, across different towns, and between industrial and city supply during wet and dry periods, so hard to determine how resource variability translates to household vulnerability. Infrastructure

19. B. Multiple Scales – Missing Linkages Arkavathy water supply Cauvery water supply Different areas are vulnerable to different supply variability pathways. E.g. selected pockets get “Cauvery supply” the rest are dependent on groundwater.

20. C. Multiple Concerns Human Well-being T= 0 Present T= X Future Drought/ Seasonal Vulnerability

21. C. Multiple concernsInadequate water supply Overall- most parts of Arkavathy basin do not receive enough public supply. (However, different data sources are not consistent.)

22. Groundwater and surface water highly contaminated C. Multiple concernsInadequate water quality

23. C. Multiple concernsDeclining SW availability In most places the Arkavathy River is completely dry.

24. C. Multiple concernsDeclining GW availability Sample hydrograph in Yelahanka* (0) Water Level (meters below ground level) (9) (14) Source: Srikanta Murthy, 2011 1974 1996 *Although groundwater levels have been increasing in places within the city mainly due to pipeline leakage

25. C. Multiple Concerns Human Well-being T= 0 Present T= X Future T= 0 Present T= X Future T= X Future T= 0 Present Chronic Scarcity/ Inequity Resource Unsustainability Drought/ Seasonal Vulnerability

26. Research Methods Land, Labor, Commodity Markets Assets, Income Land use Land use decisions Global Climate Change Adaptation, coping Water Users Livelihood / Domestic Water / Economic Production / Environment Outcomes Institutions Water Quantity and Quality Available Watershed Temp and Rainfall Infrastructure Wastewater Topography, Geology, Soils Extraction

27. Need an approach that considers all these A. Multiple Stressors B. Multiple scales with missing linkages C. Multiple Concerns

28. THANK YOU!! Team Members IDRC CCW SharachchandraLele VeenaSrinivasan Bejoy Thomas PriyankaJamwal ShrinivasBadiger DurbaBiswas PennanChinnasamy MeghanaEswar T. Zuhail Kiruba Haran KarthikMadhyastha Swati Sulgana SanjeevKenchaigol Interns Malvika Sayan Tagore Nagaraju Shilpa Tata Social Welfare Trust Project Sheetal Deepthi