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

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

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 Water Supply (Quantity and Quality) Stressors Shocks Seasonality Rainfall Temperature Infrastructure Policies Livelihood / Domestic Water Security Outcomes “Top-Down” View of Water Supply Vulnerability

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

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

8. A. Multiple Stressors: 0 500 1500 1000 Both climate models and station rainfall data suggest slight increasing trend in annual rainfall 1900 1950200019751925 Doddaballapur Annual Rainfall (mm/year)

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

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

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

12. 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 2: GW Pumping Hypothesis 3: Eucalyptus Plantations Hypothesis 4: “Million Puddle Theory” Hypothesis 1: Temperature rise

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

18. B. Multiple Scales – Missing Linkages Institutions Infrastructure 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.

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

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

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

22. C. Multiple concerns Inadequate water quality Groundwater and surface water highly contaminated Groundwater samples by taluk (sub-district) Concentration* (mg/L) Heavy metalsFecal coliform Cr 6+ :0.05 mg/l Al 3+ :0.03 mg/l 0 MPN/100L Anekal 0-364 PeenyaCr 6+ = 16-320-88 DoddaballapurAl 3+ = 350-300 Kanakapura Present Ramanagara Present

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

24. C. Multiple concerns Declining GW availability 1974 1996 (14) (9) (0) Water Level (meters below ground level) Source: Srikanta Murthy, 2011 Sample hydrograph in Yelahanka* *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 Resource Unsustainability T= 0 Present T= X Future Drought/ Seasonal Vulnerability T= 0 Present T= X Future Chronic Scarcity/ Inequity

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

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 Sharachchandra Lele Veena Srinivasan Bejoy Thomas Priyanka Jamwal Shrinivas Badiger Durba Biswas Pennan Chinnasamy Meghana Eswar T. Zuhail Kiruba Haran Karthik Madhyastha Swati Sulgana Sanjeev Kenchaigol Interns Malvika Sayan Tagore Nagaraju Shilpa Tata Social Welfare Trust Project Sheetal Deepthi