Bangladesh Flood Risk Update Flood Risk Rising World Food Programme (WFP) Disaster Risk Reduction (DRR) 29 th August 2008

Overview Factors contributing to higher risk Regional Geography; Up-Stream Perspective Situation in Bangladesh Situation Upstream Risk of significant flooding is now higher; situation has changed Higher risk areas in Bangladesh Preparedness Actions Needed

Regional/Upstream Perspective Critical In an average year, during May-October, about 1 trillion cubic meters of water flows through Bangladesh 17% of that water comes from rainfall inside Bangladesh 83% is “In-flow”; from rain and rivers outside the country 78% of the in-flow comes via the three main rivers; Bhramaputra-Jamuna, Ganges/Padma, and the Meghna Regional perspective (i.e. Upstream monitoring…) matters; - - A lot !! Source: Banglapedia

M e g h n a Brahmaputra Ganges-Padma Tista Assam Bihar Assam Sikkim Nepal Assam Meghalaya Bhutan Up-Stream Basins and Rivers 1. Bihar/W. Bengal: Ganges-Padma 2. Assam: Brahmaputra-Jamuna + Sikkim: Tista 3. Meghalaya/Assam: Meghna

Approach/Methodology For Each Basin (Map-Zone) we look at Known/Confirmed Flooding Events (if any) Causes; Updates River Levels: current River Level: forecasts and trends Rainfall: forecasts and trends Flood Risk:near term (approx. next 3-5 days)

M e g h n a Ganges-Padma 1 Assam Bihar Assam Nepal Meghalaya Bhutan Up-Stream Basins and Rivers 1. Bihar/W. Bengal: Ganges-Padma Sikkim

Major Floods in Bihar India What Happened? Nepal’s Kosi River Dam breaks; 18 th August; embankments downstream breached Major flooding occurs in Nepal, and downstream in Bihar Bihar: 2-3 Million people affected, Nepal: more than 100,000 displaced

Where in Nepal and India? Proximity to Bangladesh? Origin of Kosi Flood W. Bengal Kathmandu Nepal

Causes of Kosi Flood? Heavy Rainfall? Rainfall: 11 th -20 August 2008 Percent of Normal 2008 vs. Avg. ( % Change ) 400% 200% 125% 110% 90% 75% 50% 25% 10% Notes: 1.Kosi Dam breaks 18 th August 2.Rainfall was 2 to 4 times ( %) higher than Normal for period 11 th -20 th August. 3.Heavy Rains not wide-spread; but location specific at Nepal-India Kosi area border. 4. Not entirely clear whether rain highlighted in map played a “causal” role. 5. Rainfall Source: USAID FEWSNET RFE-2 6. “Normal” based on a 7 yr. Average. Nepal India Bangladesh Bhutan Bihar West Bengal West Bengal

Proximity to Bangladesh? Zoomed View Nepal Bihar Bangladesh Rajshahi Nawabganj Rangpur Bihar W. Bengal

FFWC Padma Stations relatively close to W.Bengal/Bihar What is happening w/ river levels in these areas? Source: FFWC 29 Aug Source: Google Maps, Maplandia

Graphs of Water Levels (Hydrographs) 2 FFWC Stations; Padma River Nawabaganj District Trends; Flat/Steady Trends at 3 Normal (Green) Stations also flat/steady

What is happening w/ river levels Up-Stream: Bihar and Surroundings ? 21 Stations at or above Warning Level. 13 of 21 at Danger Level or Higher 8 of 21 at Warning Level or Higher and below Danger Level Source: India Central Water Commission River level measurements taken morning of 29 th August Information above pertains to Bihar, W. Bengal, Jharkhand Data changes Frequently; latest Updates available at : water.com/ffs/index.htm water.com/ffs/index.htm

Up-Stream River Level Trends Bihar and Surroundings Number of Stations 26 Aug27 Aug28 Aug29 Aug Warning Level (or Higher) Danger Level (or Higher)

Rainfall Forecast: Bihar and Surroundings Total Rain: Morning of 29 th Aug. thru Morning of 1 st Sept. Bihar and Surroundings mms. Rain Forecast: Very Light to Light

What is happening w/ river levels Up-Stream: Assam and Surroundings ? 8 Stations at or above Warning Level. 3 of 8 at Danger Level or Higher 5 of 8 at Warning Level or Higher and below Danger Level Source: India Central Water Commission River level measurements taken morning of 29 th August Information above pertains to Bihar, W. Bengal, Jharkhand Data changes Frequently; latest Updates available at : water.com/ffs/index.htm water.com/ffs/index.htm

M e g h n a Brahmaputra Ganges-Padma Tista 2 Assam Sikkim Nepal Assam Meghalaya Bhutan Up-Stream Basins and Rivers 2. Assam: Brahmaputra-Jamuna + Sikkim: Tista

Up-Stream River Level Trends Assam and Surroundings Number of Stations 26 Aug27 Aug28 Aug29 Aug Warning Level (or Higher) Danger Level (or Higher)

Rainfall Forecast: Assam and Surroundings Total Rain: Morning of 29 th Aug. thru Morning of 1 st Sept. mms. Rain Forecast: Light to Moderate Assam and Surroundings

What is happening w/ river levels Up-Stream: Meghalaya-Assam and Surroundings ? 8 Stations at or above Warning Level. None at Danger Level or Higher One at Warning Level or Higher and below Danger Level Source: India Central Water Commission River level measurements taken morning of 29 th August Information above pertains to Bihar, W. Bengal, Jharkhand Data changes Frequently; latest Updates available at : water.com/ffs/index.htm water.com/ffs/index.htm

M e g h n a Brahmaputra Ganges-Padma Tista Nepal Bhutan Up-Stream Basins and Rivers 3. Meghalaya/Assam: Meghna Meghalaya 3

Up-Stream River Level Trends Meghalaya-Assam and Surroundings Number of Stations 26 Aug 27 Aug28 Aug29 Aug Warning Level (or Higher) Danger Level (or Higher)

Rainfall Forecast: Meghalaya-Assam and Surroundings Total Rain: Morning of 29 th Aug. thru Morning of 1 st Sept. mms. Rain Forecast: Light to Moderate Assam Meghalya

Bangladesh South-East Chittagong, Cox’s Bazar and Surroundings In addition to the analysis presented in previous slides Very Heavy Rain has fallen in SE Bangladesh; and Flash Flooding has occurred Some assistance has been provided; GoB and UNICEF

Conclusions/Recommendations Flood Risk in Bangladesh has become higher in recent days; mostly because of heavy rain and high river levels Up-Stream; and also because of heavy rain in some areas of Bangladesh Situation has deteriorated and may continue to deteriorate in coming days Close Monitoring needed Stepping up preparedness for potential rapid response warranted