Tennessee Technological University Faisal Hossain Tennessee Tech UNIVERSITY Potential Role of SWOT for International Issues of Surface Water Monitoring Faisal Hossain Department of Civil and Environmental Engineering Tennessee Technological University SWOT Hydrology Workshop The Ohio State University, Sept 15-17, 2008

Tennessee Technological University Faisal Hossain Tennessee Tech UNIVERSITY OUTLINE 1.Society – What are the policy implications that freely available water storage (+flux) would have for water management? 2.Potential of SWOT for Bangladesh: Accuracy of SRTM data for discharge estimation of Brahmaputra river (braided) in Bangladesh.

General Problem of Transboundary Flow Forecasting in the Developing World: The Story of the Niger River Question: How does a downstream nation monitor early the evolution of river flow across political boundaries of 5 nations, 11 administrations and a diverse landscape? km long, 2,113,200 km 2 2. Flows through 5 countries 4. Frequent river flooding induced by heavy rainfall 3. Drainage area comprised of 11 countries 5. Diverse climate, rainfall regime, soil conditions, topography = varying response of landscape to rainfall Tennessee Tech UNIVERSITY

Tennessee Technological University Faisal Hossain Tennessee Tech UNIVERSITY  Hydro-political limitations worsen at the shorter time scales 214 International River Basins in 1979 UN Register 261 in 2002 (Updated) 145 countries are associated in IRBs.. > 50% of total surface flow Percentage Area (of an IRB) Number of Countries 91-99% % % % % % % % %9 1-10%11 Transboundary Flow Forecasting: The Global Picture on International River Basins Source: Dr. Aaron Wolf, Oregon State University Distribution of treaties with allusion to transboundary flood management

Tennessee Technological University Faisal Hossain Tennessee Tech UNIVERSITY Overview of Surface Water-related Hazards in Bangladesh Average inundation 22% 68% area inundated in 1998 About 1/4 th of the country susceptible to tidal surges Over 3000 km river bank will be eroded by 2025 Water scarcity in 7 months a year The geographical location and average land levels of Bangladesh are conducive to Flood Erosion Storm Surge Drought Source: Institute of Water Modeling - Bangladesh

Tennessee Technological University Tennessee Tech UNIVERSITY Routine Surface Water Monitoring Needs of Bangladesh Flood Forecasting during Monsoon Season. About 30 river stations. Forecasts for public - 3 days. 10 day to seasonal forecast under prototype. Source: Flood Forecasting and Warning Center; Danger Level RHWL 3-Day Water Level Forecast

Challenges of Flood Forecasting in Bangladesh Bangladesh comprises only 7% of Basin area. Lack of upstream (transboundary) stream flow in real-time limits forecasting range to ~ 3 days. (10 day ensemble forecast in 2009) High costs and maintenance issues for In- situ rainfall and stream gage network 21 day forecast is IDEAL according to Asian Disaster Preparedness Center for South Asian nations Tennessee Tech UNIVERSITY

Impact of Large-scale Water Diversion Projects in Upstream Nations? Tennessee Tech UNIVERSITY The Indian River Linking Project (IRLP) Increase of anthropogenic alteration of long-term surface water distribution through planned large- scale water resources project in upstream nations will make downstream nations more dependent on water storage-level information from SWOT. Use of stand-alone ‘natural’ models will not be able to provide answers to all key questions on future water availability.

Tennessee Technological University Tennessee Tech UNIVERSITY Space-borne Discharge Estimation of Brahmaputra River (a Braided River) What is the Uncertainty of satellite interferometry (SRTM) - based discharge estimation of braided rivers? SRTM Overpass – Feb 20, 2000 Land/Water Mask SRTM elevation data Braided rivers have not been well-studied

Tennessee Technological University Faisal Hossain Tennessee Tech UNIVERSITY Space-borne Discharge Estimation of Bangladesh Rivers Bathymetry data of Brahmaputra river cross sections from IWM Water slope derived from SRTM Uniform flow conditions: Water surface slope=Energy gradient: Manning’s equation

Tennessee Technological University Tennessee Tech UNIVERSITY Hamski et al (2008) – ASLO – American Society of Limnology and Oceanography Conference March 2-7, Orlando, Florida. Low flow (dry season) discharge estimated by satellite interferometry comparable to natural low-flow variability Space-borne Discharge Estimation of Bangladesh Rivers

BM establishment with RTK-GPS Tidal Discharge Measurement ADCP Measurement Spot Level using Total Station Alignment Survey using ProXR DGPS Bathymetry Charting Availability of Infrastructure for Ground Truth Data for SWOT in Bangladesh IWM – Bangladesh offers a range of archived data and river measurement capability for SWOT validation Tennessee Tech UNIVERSITY

Tennessee Technological University Faisal Hossain Tennessee Tech UNIVERSITY ACKNOWLEDGEMENTS 1.Dennis Lettenmaier – for facilitating the connection to SWOT 2.Ohio State University – Doug Alsdorf and James Hamski 3.University of Mississippi: Dr. Azad Hossain. 4.Institute of Water Modeling – Bangladesh: Abu Saleh Khan, Zeaul Huq, Mahbubur Rahman and Bushra Nishat. 5.Dhaka University - Bangladesh: Dr. Khaled Hassan.

Tennessee Tech UNIVERSITY THANK YOU! QUESTIONS? Main Message Recap 1. Increase of anthropogenic alteration of long-term surface water distribution through planned large-scale water resources project in upstream nations will make downstream nations more dependent on water storage-level/flux information from SWOT for day to day and long- term planning 2. Ganges-Brahmaputra- Meghna Basins are home to one fifth of humanity with regions vulnerable to sea level rise. 3. Virtual SWOT should include Ganges-Brahmaputra- Meghna Basins