Andhra Pradesh Flood Modelling
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2/4/2010 FRAMEWORK DEVELOPMENT OF FLOOD HAZARD MITIGATION MODELLING and MANAGEMENT Decision Support Systems Andhra Pradesh flood modelling • 24 rivers to be modelled, including Godavari, Krishna, and Pennar • Flood forecasting in coastal districts • Network of real-time river and rainfall gauges • Rain gauges – 50 Nos • Rain & River gauges – 16 Nos Dr. K. J. Ramesh Adviser and Scientist ––‘G’‘G’ • River gauges – 28 Nos Ministry of Earth Sciences • Meteorological Stations – 5 Nos Govt. of India Accumulated Rainfall Area Plot Image Accumulated Rainfall Area Plot Image Accumulated Rainfall Area Plot Image Accumulated Rainfall Area Plot Image 1 2/4/2010 Accumulated Rainfall Area Plot Image Accumulated Rainfall Area Plot Image Accumulated Rainfall Area Plot Image Accumulated Rainfall Area Plot Image Accumulated Rainfall Area Plot Image Accumulated Rainfall Area Plot Image 2 2/4/2010 RAINFALL AT GULLALAMODHA 3 2/4/2010 Hazard Mitigation Modeling System for Floods Flood forecasting system Rainfall Data UP Inflow from Cyclone Model Model into Telemetry Data River River Channel IMD Network Mouths Survey ••Flood Watch Satellite Derived (region) Bank Levels Developed and Calibrated 1:1Mil Real time data management and To develop for Additional Inputs 1:250000 and From cyclone models from : 1:50000 display Measured Telemetry and Discharges ••UP Model Gauge Network from MIKE 11 CWC, Hydrology Network from IRC** Hydrological modelling 3D-DEM Completed 1: 50K ••Mike11 FF Decision Support System Process: 1:25 K GIS Offline Flood Simulated (Coastal Interface Flow Levels Watch 20Km stretch Hydrodynamic modelling with (Overlaying, and possible only) Zooming and Bank Other Data Input Overflows realreal--timetime updating ••Mike11 GIS Quantification VALUE ADDITION of Flooding Advisories/ Bulletins •Damage Quantification, Flood areas •Advisories for facilitating relief routing, Flood mapping and topographic Depth/Duration/ •Increase in Lead time Extent •Delta Water Management and Water Quality Management data management •Flood Control Strategies (long-term and short term mitigation plans) 4 2/4/2010 Rivers Models 1. Krishna 13. Gundlakama 2. Godavari 14. Swarnamukhi 3. Pennar 15. Kandaleru 4. Vamsadhara 16. Pampa 5. Nagavali 17. Elleru 6. Gosthani 18. Vogaru vagu 7. Meghadrigadde 19. Rammileru 8 Sarada 20. Errakalva 9 Varaha 21. Paleru 10. Thandava 22. Manneru 11. Tammileru 23. Nallamada 12. Gunderu 24. Romperu Extent of Proposed River Modelling UP Model GODAVARI RIVER • Upscaled Physically-based model designed: VISHAKHAPATNAM HYDERABAD – to simulate water exchanges between the land surface and the atmosphere KRISHNA RIVER – to simulate lateral transfer of water, solutes KEY and sediment BOUNDARY GAUGING STATION GAUGING STATION WHERE UPDATING WILL BE PERFORMED WITHIN MIKEFF – to be applicable from catchment-scale to DETAILED MIKE11 MODELS OF COASTAL PLAIN BAY OFBAY BENGAL OF BENGAL AND DELTAS CATCHMENTS MODELLED BY UP MODEL continental-scale SIMPLE MIKE 11 REPRESENTATIONS PENNAR RIVER MAJOR DELTA REGIONS COASTAL PLAIN SCALE 0 KM 100 UP Element Flow Routing • Precipitation • Channel transfer function approach An UP Element 1 • Evapotranspiration 3 – Analytic solution to St. Venant equations SNOW CANOPY PACK 3 6 – Linear superposition 3 2 SURFACE • Soil water storage 4 5 WATER • Surface runoff 8 SOIL WATER INTERFLOW MAIN 5 CHANNEL 7 GROUNDWATER NETWORK 1 PRECIPITATION Q 2 THROUGHFALL & SNOWMELT 3 EVAPORATION & TRANSPIRATION 4 INTERFLOW DISCHARGE 5 GROUNDWATER DISCHARGE 6 SURFACE RUNOFF 7 PERCOLATION & CAPILLARY RISE Q 8 INTER-ELEMENT EXCHANGES t 5 2/4/2010 6 2/4/2010 MIKE11 Model • MIKE11 is a one-dimensional mathematical model of river flow • Solves the 1-D form of the St.Venant equations providing a fully dynamic representation of river flow • Linkage to GIS, Flood Forecasting, and Flood Warning packages 7 2/4/2010 Basic data requirements for MIKE 11 GIS modelling • Flood Mapping: MIKE 11-GIS • River cross-sections • Fully integrated GIS based flood modelling • Maps of floodplains • Centred on ArcView GIS • Leverages full power of GIS for modelling • Historical river flow data • Pre-processing: Floodplain schematization • Tidal variations • Post-processing: Inundation maps • Data on structures along river that affect Comparison maps Duration maps flow • Analysis with other GIS data River Pennar Input Data Model • Daily and hourly flow data from CWC • Model extends from Somasila to Bay of Bengal • Somasila Dam outflow discharges from • The total modelled length of the River Penneru is around 117 km Irrigation Dept. • River Channel Survey Data • Major structure is Somasila dam • One existing CWC station at Nellore is present within model reach • Topographic data from Survey of India Schematic diagram of Pennar model with UP inputs Calibration of Pennar river flooding of August 1988 Comparison of observed and measured water levels at Nellore gauge for 1988 event (Somasila Dam discharges decreased by 20%) 13 12 11 Modelled 10 CWC Observed 9 Water Level (m ) 8 7 25/08/1988 04/09/1988 14/09/1988 24/09/1988 04/10/1988 0:00 0:00 0:00 0:00 0:00 Comparison of observed and measured discharge at Nellore gauge for 1988 event (Somasila Dam discharges decreased by 20%) 3500 3000 2500 2000 Modelled 1500 CWC Observed 1000 Discharge (cumecs) 500 0 25/08/1988 04/09/1988 14/09/1988 24/09/1988 04/10/1988 0:00 0:00 0:00 0:00 0:00 8 2/4/2010 Calibration for Pennar river flooding of November 1991 Calibration for Pennar river flooding of October 2001 Observed versus modelled w ater levels at Nellore for 1991 Comparison of modelled and observed discharge at Nellore Anicut flood event 12000 15 10000 8000 Modelled discharge 12 Modelled Observed discharge 6000 CWC Observed 9 4000 Water Level (m ) Discharge (cumecs) Discharge 2000 6 0 29/10/1991 08/11/1991 18/11/1991 28/11/1991 08/12/1991 14/10/2001 16/10/2001 18/10/2001 20/10/2001 22/10/2001 24/10/2001 0:00 0:00 0:00 0:00 0:00 00:00 00:00 00:00 00:00 00:00 00:00 Date Observed versus modelled discharge at Nellore for 1991 flood event Comparison of modelled and observed water level at Nellore 7000 Anicut 6000 18.00 5000 17.00 4000 Modelled Modeled water levvel 16.00 3000 CWC Observed Observed water level 15.00 2000 Discharge (cumecs) 14.00 1000 Water level (m) 0 13.00 29/10/1991 08/11/1991 18/11/1991 28/11/1991 08/12/1991 12.00 0:00 0:00 0:00 0:00 0:00 14/10/200 16/10/200 18/10/200 20/10/200 22/10/200 24/10/200 1 00:00 1 00:00 1 00:00 1 00:00 1 00:00 1 00:00 Date Inundation map of Nellore District (Units:Cm) Inundation map for October 2001 flood event FLOOD WATCH The Strengths of MIKE Flood Watch A Management System for Real-Time Flood Forecasting and Warning A fast and reliable system for real-time operation Direct-access time series database MIKE Flood Watch is a decision support system Integration with external databases, e.g. Oracle for real-time flood forecasting combining an Automatic import of telemetric data advanced time series data base with the MIKE 11 Data quality control and data processing facilities hydro- dynamic modeling and real-time GIS presentation facilities forecasting system, MIKE11 FF together with the Automatic forecasting and storage of results Geographical Information System (GIS), Arc Dissemination of flood maps, flood warnings, View GIS bulletins and graphics on the World 9 2/4/2010 DISTRICT INUNDATION WARNING REPORT KRISHNA DISTRICT Nellore District Flood Inundation Map Date & Time of Information : 23 April 2001 8:00 PM Fax / email output Date & Time of Transmission : 23 April 2001 8.15 PM Front page of River Pennar District Level flood inundation report River Kandaleru e.g. District Collectors, district River Swarnamukhi government offices Severely Max Flood Depth affected + 24 hours +48 hours +72 hours M ax Flood Depth and Tim e M an d als Thotlavalluru 0 m 0.25 m 1.5 m 1.5 m 25/04/01 12.00pm Pam idim ukkala 0 m 0.6 m 1.5 m 1.6 m 25/04/01 6.00pm Ghantasala 0 m 0.25 m 1 m 1.2 m 25/04/01 10.00am M achilipatnam 0 m 0.2 m 1,2 m 1.3 m 25/04/01 12.00pm 0 m 0.6 m 1.6 m 1.9 m 25/04/01 9.00pm Challapalle 0.2 5 m 1 m 1.6 m 1.7 m 25/04/01 8.00pm Avanigadda 0.2 5 m 1 m 1.5 m 1.5 m 25/04/01 7.00pm Koduru 0 m 1 m 1.4 m 1.5 m 25/04/01 8.00pm Nagayalanka DSS Outputs – District Level DSS Outputs - Bulletin 10 2/4/2010 Bulletin Types BULLETIN No. CONTENT Routine Daily State-wide Report based on both 1 Districts and Catchments/Areas Specific District Report with 2 Mandal forecast inform ation District Report with 3 indicative Mandal inundation data District Report with 4 indicative Mandal ‘assets at risk’ assessment Catchment/Area based 5 Flood Forecasting Station R e p o rt 11.