Community involvement and local flood early warning with low-tech approaches for small rivers in the Philippines Hilton Hernando Philippine Atmospheric, Geophysical & Astronomical Services Administration Olaf Neussner Deutsche Gesellschaft fuer Internationale Zusammenarbeit (GIZ) 28 May 2013, Seoul, Republic of Korea 10/23/11 Seite 1 Page 1
Philippines: average of about 30 flood events per year!! T. Marce - SW (Aug. 2004) Ondoy (Sept. 2009) SW Monsoon (Aug. 2012) T. Pedring (Sept. 2011) T.S. Sendong (Dec. 2011) T. Frank (June 2008) Ormoc Flood 1991 Typhoon Pablo (Dec. 2012) Hilton Hernando, Olaf Neussner 10/23/11 Seite 2 Page 2
Only 5 river basins with telemetered Flood Forecasting & Warning System For other smaller basin / watershed areas: CBFEWS (LFEWS) is still the best and preferred alternative. (innovative, inexpensive yet robust, strong community participation) Hilton Hernando, Olaf Neussner 10/23/11 Seite 3 Page 3
The Community-Based or Local Flood Early Warning System (CBFEWS/LFEWS) Key elements of an LFEWS: 1. Risk knowledge 2. Monitoring & Warning 3. Info Dissemination & Communication 4. Response capability Hilton Hernando, Olaf Neussner 10/23/11 Seite 4 Page 4
Binahaan Flood Early Warning System Example of LFEWS program in the Philippines Data from Rain/River Gauges in Tingib Binahaan River Pastrana Warning to Municipality Dagami Warning to Municipality Binahaan Watershed 10/23/11 Warning to Barangay 1. Data gathering 2. Warning to municipalities 3. Warning to villages 4. Warning to households 5. Evacuation Flood-prone Area Tanauan Hilton Hernando, Olaf Neussner 10/23/11 Seite 5 Page 5 Evacuation Evacuation Warning to Barangay Palo Warning Warning to Municipality tomunicipality Operation Center
RISK KNOWLEDGE Community-based Participatory risk mapping: - People know frequently occurring hazard events well (e.g. floods). - Location of households and other assets - Encoded in GIS for overlaying with existing (scientific and topographic) maps. Community-based mapping in GIS Hilton Hernando, Olaf Neussner 10/23/11 Seite 6 Page 6
MONITORING & WARNING Manual and an automatic (radio linked) rain gauges Hilton Hernando, Olaf Neussner 10/23/11 Seite 7 Page 7
MONITORING & WARNING Manual and automatic (radio linked) water level gauges Hilton Hernando, Olaf Neussner 10/23/11 Seite 8 Page 8
MONITORING & WARNING Community volunteer with display of rain sensor on the roof; below student volunteers doing rainfall observations Hilton Hernando, Olaf Neussner 10/23/11 Seite 9 Page 9
INFO DISSEMINATION & COMMUNICATION Flood Warning Levels Flood Level 1 Alert / Stand By Three stages Prepare / Get set Flood Level 2 Preparation Ready Flood Level 3 Evacuation Hilton Hernando, Olaf Neussner 10/23/11 Seite 10 Page 10 Go
INFO DISSEMINATION & COMMUNICATION Flood Warning Levels High probability of flood Flood is inevitable within some hours Flood coming any time? WL >= 1.5m @ LMWD, or RG >= 80mm/h @ LMWD. Condition (Binahaan River) WL >= 2.0m @ LMWD Flood will be at San Benito Bridge in <5 hours. WL >= 2.5m @ LMWD Flood is past San Benito Bridge and will reach other barangays any time. Hilton Hernando, Olaf Neussner 10/23/11 Seite 11 Page 11
INFO DISSEMINATION & COMMUNICATION Who needs to do what at the three warning levels? MDRRMO (Operation Centre) Radio, telephone (landline, mobile) Barangay Dev. Council (DRRM Committee) Bells, megaphone, SMS, messenger Households Hilton Hernando, Olaf Neussner 10/23/11 Seite 12 Page 12
INFO DISSEMINATION & COMMUNICATION Municipal DRRM Office Warn all BDRRMCs in flood-prone area. Inform about flood, advice to start slow preparatory activities, gather children, animals Alert MDRRMO staff and ask them to go on standby Alert Search and Rescue Teams and ask them to go on standby Inform PNP Check status of/access to and prepare municipal Evacuation Center Listen to status report on DYMP Warn all BDRRMCs in flood-prone area. Advice households to prepare for evacuation: Prepare Emergency Pack for five days (water and food, cloth, etc.) Secure vulnerable items in household Prepare and open municipal evacuation Centers (e.g. lights, water, food, toilets, beds, blankets, medicine, etc.) Listen to status report on DYMP Advice all BDRRCs in flood-prone area. Order households to evacuate and bring emergency pack for at least 5 days Check evacuated houses Head count at evacuation center Listen to status report on DYMP Hilton Hernando, Olaf Neussner 10/23/11 Seite 13 Page 13
RESPONSE CAPABILITY Drills Active participation of locals in providing warnings, e.g. Bells, etc. Evacuation Drill in St. Bernard, Southern Leyte Evacuation drills strengthen LFEWS ownership of communities Hilton Hernando, Olaf Neussner 10/23/11 Seite 14 Page 14
RESPONSE CAPABILITY Improved Evacuation Centres Hilton Hernando, Olaf Neussner 10/23/11 Seite 15 Page 15
RESPONSE CAPABILITY Search & Rescue Capacity Training Strong Participation of Community Members Hilton Hernando, Olaf Neussner 10/23/11 Seite 16 Page 16
Water level [m] LFEWS in action Alert Level 2 issued Alert Level 3 issued Alert Level 3 lifted Flood starts Hilton Hernando, Olaf Neussner 10/23/11 Seite 17 Page 17
Community members and governmental rescue professionals work hand in hand Ormoc, Leyte, 27/28 Dec. 2011 Bulacan, Sept. 2011 Hilton Hernando, Olaf Neussner 10/23/11 Seite 18 Page 18
Summary How is the Local Flood Early Warning System established and how does it perform? LFEWS costs 30,000 40,000 US$ in the Philippines Cost Benefit Analysis says this is profitable after eight years (less damages than costs) Run by non professionals but with guidance from professionals Many successful warnings were issued by eight LFEWS Very low failure rate (one false alarm only) Population has more time to prepare for floods; damages reduced Can be replicated in other countries without a problem Involvement of volunteers in response strong but weak in data transmittal Hilton Hernando, Olaf Neussner 10/23/11 Seite 19 Page 19
Way forward... Flood modelling Simulation of situations that did not happen yet in order to be able to prepare for them Replication in the Philippines: PAGASA and GIZ currently supports the establishment of eight more LFEWS in different parts of the country Hilton Hernando, Olaf Neussner 10/23/11 Seite 20 Page 20
Flood model Ormoc City 525mm/ 24h (Theory) Juan Hilton Hernando, Olaf Neussner 10/23/11 Seite 21 Page 21
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