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Environmental Flows Assessment

Environmental Flows Assessment. Objective Based Flow-Setting In certain cases, people intend to have specific pre-defined ecological, economical and social objectives for the river. Scenario Based Flow-Setting

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Environmental Flows Assessment

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  1. Environmental Flows Assessment • Objective Based Flow-Setting • In certain cases, people intend to have specific pre-defined ecological, economical and social objectives for the river. • Scenario Based Flow-Setting • if water managers are able to understand and make decision on water allocations and scenarios for trade offs in managing and balancing the water demands/requirements.

  2. Building Block Methodology • Building Block Methodology – one of the most comprehensive methodology • Bottom up approach • Much detailed and can be tailored to suit local conditions • Most frequently used holistic methodology • Rigorous and well documented

  3. Building Block Methodology • Flexible to accommodate other local aspects, like religious and spiritual requirements (hence applicable for Indian rivers) • Functions well in data-rich and data-poor situations • Links to external stakeholders and public participation processes • Applicable to regulated and non-regulated river regimes • Moderate to highly resource intensive

  4. Building Block Methodology

  5. Stage A: Scoping Task 1: Initiate EFA assessment (level of detail, define methodology) Task 2: Constitution of the assessment team Task 7: Ecological and Social Importance and Sensitivity Task 3: Zone the study area Task 8: Define reference conditions Task 1: Hydrological yield analysis Task 4: Habitat integrity Task 9: Define present ecological status Task 2: Scenario analysis Task 5: Site Selection Task 10: Define environmental objectives Task 3: Decision Task 6: Surveys and measurements Biological Surveys Hydraulic survey Hydrological analysis Geomorphological survey Water Quality analysis Social survey Stage D: Negotiation Stage B: Preparation for theAssessment Stage C: EFA Setting workshop Stage E: Implementation and compliance monitoring

  6. Flow Indicators Fish, Dolphins, Invertebrates, Algae, Religious rites, Livelihoods, Channel processes Habitats Activities Processes Required • Objectives • GANGA EFA: Promote the sustainable use of water resources in the Ganga to: • - Ensure ecological integrity • Provide livelihoods • Maintain sacred values Hydrology Cubic metres per second of Water required Hydraulics Depth Velocity Width Substrate 7

  7. Zone I: Upper Reach (Gangotri to Rishikesh) Zone II: Reference zone (U/S of Garhmukteshwar to Narora) Zone III: Middle Reach (Narora to Farrukhabad) Zone IV: Lower Reach (Kannuaj to Kanpur) Rishikesh Narora Kannauj

  8. Zone 2 U/S of Garhmukteshwar to Narora (Reference Zone) Zone 1 Gangotri to Rishikesh Zone 3 Narora to Farrukhabad Zone 4 Kannauj to Kanpur

  9. Components • Hydrology - Identify and review previous hydrological modeling studies and assessment of their usability - To set up model and calibrate under existing conditions of land and water use - Examine the feasibility of different ways of modeling the past ‘natural’ and present-day flows, using observed flow data

  10. Components • Fluvial Geomorphology and hydraulic modeling for maintaining sustainable flows • Analysis of sediments in the river, and the assessment of the effects that will result from different flow regimes • Analyse the channel and floodplain morphology in terms of the geomorphic features, and their stability • Generate the cross section and longitudinal profile for hydraulic modelling • Habitat preferences of selected Aquatic species • Assess present condition in terms of the difference between the reference condition and survey results • Describe measured depths, average velocities and substratum types most commonly associated with sensitive species and families, and/or with maximum biodiversity

  11. Components • Economic and Livelihood objectives for Maintaining Sustainable Flows - Evaluate livelihood activities and its implications on environmental flows of the river • Assessment of Cultural & Spiritual in stream flow required for Maintaining Sustainable Flows • Representation of the river in mythology, folklore, folk art and popular literature and art • Historical evidence of civilizations along the river, and its influence on society • Cultural, Religious, spiritual importance of the Ganga, with focus on rituals and festivals 6. Water Quality and Pollution • Generation of data on water quality parameters that is not available from any sources, but considered essential by the water quality group (samples from 30 locations) • Assessment of various types of pollution loads in different stretches/sub-stretches

  12. Arriving at E-Flows STEP 1: Hydrology and Hydraulics Cross Sections for each zone

  13. STEP 2: Flow motivations Flow recommendations based on requirements of biodiversity, Livelihoods, Culture/Spiritual needs, Geomorphology

  14. Maintenance Flows The Maintenance Flows are for "normal" years, not very wet or not very dry, here one would expect all the ecological functions and processes: • fish breeding • floodplain wetlands full • sediment transport etc. Maintenance Flows would be equaled or exceeded during 70 years out of 100; however flows would be lower for 30 years out of 100 or in other words, 70% probability on the flow duration curve. For a long-term E-Flow, the water volume required would be at maintenance recommendations or higher for 70% of the time, and between drought and maintenance for 30% of the time.

  15. STEP 3: Calculating critical flows

  16. Critical flows • Kaudiyala: • January maintenance flow: fluvial geomorphology • August maintenance flow: biodiversity • Kachla Ghat & Bithoor: • August flows (both during maintenance and drought years): cultural and spiritual • Almost half of the critical flow recommendations were influenced by biodiversity requirements

  17. STEP 4: Calculating annual E-Flows requirements • Driest and wettest months under maintenance and drought conditions (January – driest month and August – wettest month) • E-Flows values were calculated, based on inputs from working groups, by hydrologist for other months of the year by means of interpolation • Monthly flow volumes for each month of the year for low-flow and high-flow components calculated

  18. Arriving at E-flows

  19. Results: Zone 1, Maintenance Flows Site -Kaudiyala E-Flows: 72% of Mean Annual Runoff Present day flows could not be calculated, as flow release data from the Tehri Dam was not available 72% MAR

  20. Results-Zone 3: Narora–Farrukhabad Maintenance Flows 45% MAR Site –Kachla Ghat E-Flows requirement: 45% of MAR Present day flows does not meet E-Flows requirement during the lean season

  21. Results - Zone 4: Kanauj- Kanpur Maintenance Flows Site EF4 – Bithur E-Flows: 47% of MAR Present day flows not meeting E-Flows requirements for lean months 47% MAR

  22. Key Issues Access to observed long term hydrological data, is critical for assessing flows and this would have considerably increased the confidence in the environmental flow assessment. Further calibration and verification of the existing rated cross-sections, and the establishment of additional cross-sections, would also increase confidence in the flow recommendations Relationships between indicator fish, invertebrates and flow would allow more precise flow recommendations More precise relationships between water quality parameters and flowwould have allowed the prediction of the effects of recommended flows on water quality to be assessed

  23. E-flows • Not a one time flow; Regime of flows • Assess E-flows using a holistic approach: hydrology, hydraulics, fluvial geomorphology, water quality, socio-cultural-spiritual, biodiversity and livelihood • Need to be an integral part of the EIA & CIA • Bottoms up-project, sub-basin to basin level; • Existing projects • Trade-off analysis • Need to place it in the context of river basin management plan

  24. E-flows • Implementation & monitoring • Joint monitoring • Whether required releases are being made • Impacts • Adaptive process needed in E-flows assessment and implementation • The EF process should be embedded in a framework of inclusive stakeholder understanding and participation, and preferably within a broader context of IWRM

  25. Partners Facilitation: Prof Jay O’Keeffe, (formerly UNESCO-IHE, Netherlands) & Dr Vladimir Smakhtin, IWMI Biodiversity: Prof Prakash Nautiyal, Garhwal University Cultural/Spiritual: Prof Ravi Chopra, People’s Science Institute Livelihoods: Prof Murali Prasad, IIT Kanpur Geomorphology: Prof Rajiv Sinha, IIT Kanpur Water Quality: Prof Vinod Tare, IIT Kanpur Hydraulics: Prof A K Gosain, IIT Delhi Hydrology: Dr Vladimir Smakhtin, Dr Luna Bharati, IWMI

  26. THANK YOU

  27. Building Block Methodology

  28. Desktop (Half-Day) Different EF Assessment Methodologies Over 200 methodologies

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