Flood Alert Flood Alert
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FLOOD ALERT FLOOD ALERT INTRODUCTION Based on the forecasts by the National Meteorological Agency (NMA), the DRMFSS‐led Flood Task Force comprised of representation from National Meteorological Agency (NMA), sectoral line ministries, UN agencies, NGOs and donors, under the Disaster Risk Management Technical Working Group (DRMTWG) has been reactivated to closely monitor the flood situation and facilitate timely preparedness and response measures. The Task Force prepared this Flood Alert, which indicates the forecast for the 2011 kiremt season and identifies flood risk areas in order to trigger timely mitigation, preparedness and response measures. The alert will be regularly updated inline with further forecasts by NMA and the development of the situation on the ground. Based on the alert, the taskforce will prepare a Flood Contingency Plan. BACKGROUND Flood, as one of the major natural hazards in Ethiopia, impacts lives and livelihoods in parts of the country. Flooding in Ethiopia is mainly linked with the national topography of highland mountains and lowland plains with natural drainage systems formed by the principal river basins. Most floods in the country occur as a result of river overflow following prolonged rainfall that causes rivers to runoff and inundate areas along their banks in lowland plains. Among the major river flood‐prone areas are parts of Oromia and Afar regions lying along the upper, mid and downstream plains of the Awash River; parts of Somali Region along the Wabishebelle, Genale and Dawa rivers; low‐lying areas of Gambella along the Baro, Gilo and Akobo rivers; downstream areas along the Omo River in SNNPR and the extensive floodplains surrounding Lake Tana and the banks of Gumara, Rib and Megech rivers in Amhara (see Map 1 below). Flash floods, which occur in lowland areas when excessive rain falls in the highlands, are also frequent in central and western Tigray; North and South Wollo, West Gojjam and Oromia zones (Amhara); North and West Shewa (Oromia); Wolayita, Hadiya, Guraghe and Sidama zones (SNNPR) and Dire Dawa and Jijiga Towns. Such flash floods are characterized by sudden onset with little lead time for early warning and often resulting in considerable loss of life and property. In addition to the historically flood prone areas in the country, new areas such as East and West Harerghe zones (Oromia) are emerging as flood‐vulnerable due to the effects of land degradation in the areas. 2 Map 1: Flood Prone Areas Flooding usually occurs at the peak of the kiremt rainy season (July and August) in most flood‐prone areas. In Somali and Gambella regions, flooding often happens during the months of August/September. Heavy belg/gu/deyr rains can also cause flooding. In Somali Region, excessive down pours could induce floods in October/November. In 2011, however, the belg rains will have lower contribution to the kiremt season flooding due to their poor performance and the resultant low soil saturation. 3 WEATHER OUTLOOK FOR THE KIREMT 2011 The National Meteorological Agency (NMA) weather outlook for the 2011 kiremt (June to September) season anticipates weak La Nina to near‐neutral global episodes during the season. The outlook indicates that the closest analogue years for the 2011 kiremt season are 1996, 2000 and 2008. Additionally, years 1974 and 1989 have been identified as analogue years. The 2011 kiremt weather forecast indicates:‐ • Normal onset and withdrawal of the kiremt rains; • The performance of the kiremt rains will be normal to above‐normal in South‐western, western, and central parts of the country; • The seasonal rains will peak in end of July and August; • There will be significant risk of flooding in flood prone areas of the country; • Occurrence of drought/moisture stress during the season is highly unlikely. Source – NMA 4 FORECAST FOR JUNE 2011 The NMA forecast for June 2011 indicates that a generally normal rainfall is likely to occur in the western half and central parts of the country. Accordingly, the kiremt rainfall in most of Amhara, Benishangul‐Gumuz, central and western Oromia, and most of SNNPR is expected to be normal to above‐normal during the month. On the other hand, Tigray, eastern Amhara, eastern Oromia and neighboring regions will have close‐to‐normal precipitation while some pocket areas will have below average rains. Lowland areas in eastern, southeastern and southern Ethiopia, where the dry season has already set in, are expected to remain dry except few pockets that will receive intermittent showers. Overall, the rains during the month would be favorable for meher agricultural activities, improvement of water and pasture availability and development of late planted belg crops as well as recently planted long‐cycle crops. Despite the forecasted favorable weather condition that will prevail during the month, NMA warns that heavy rainfall in western, central and northern Ethiopia could induce flash floods in some localities. RIVER WATER LEVELS Overall, the current water level in the dams is not at concerning level. According to the monitoring data (June8, 2011) from Ministry of Water and Energy (WoWE), the current water level in the major dams stands at: Koka 103.49 m; Melka Wakena 2509.78 m; Tana 1785.98 m; Gibe 1655.03 m; Fincha 2215.02 m; and Tekeze, 1123.09 m. Seasonal reservoir level predictions are undertaken based on analogous years and meteorological forecasts which are required to determine when water should be released from the dams in order to minimize the risk of flooding. FLOOD RISK AREAS AND THE PROSPECT OF FLOODING In line with the NMA forecast, flooding is expected in all flood prone areas of the country with high probability in western, northwestern and central parts of the country. The kiremt rain this year started slightly earlier than normal in many areas of the country. This could heighten levels of soil saturation, increasing the concern for possible landslides and flooding. Amhara: Expansion and increase in surface water levels in Lake Tana, and overflow of the Rib and Gumera rivers in South Gondar, Gilgel Abay river in West Gojam, and Dirma and Megech rivers in North Gondar can cause flooding in surrounding areas, including Fogera, Libo Kemkem and Dera (South Gondar); Achefer, Bahir Dar Zuriya and Bahir Dar Town (West Gojjam). Similarly, pocket areas in Antsokia (North Shewa); Kobo and Delanta (North Wollo); Wegdi, Dawint, Mekdela, Kalu, Werebabo, Tenta, Legambo, Albuko and Argoba (South Wollo); Dembia (North Gondar); and Dewa Chefa, Kemise Town, Jile Tumuga and Artuma Fursi (Oromia) are also prone to falsh flooding that originate from neighboring highland areas. In 2011, areas surrounding Lake Tana are expected to experience flooding. Gambella: Among the major rivers in the region that cause flooding are Baro, Gilo, Jikawo and Akobo. Flood‐prone woredas include Akobo, Lare, Itang, Gambella Zuria, Gambella Town, Jor, Gog, Jikawo, Wanthoa, Dima, and Lower Abobo. Gambella is one of the areas where high risk of flooding is indicated this year. SNNPR: Dasenech and Nyangatom woredas in the lower parts of Omo River, and areas surrounding Woito River in South Omo zone as well as Shashego woreda in Hadiya zone are 5 among the flood‐prone areas in the region. Other flash flood and landslide‐prone areas include Humbo and Kindo Koisha (Wolayita), Kemba, Bonke, W/Abaya, and Arbaminch Zuria (Gamo Gofa); Humbo (Wolayita); Hula, Dale, Loka Abaya, Shebedino woredas and Awassa town (Sidama zone); Kochere (Gedeo); Shashego (Hadiya); Sodo Kella (Gurage); Dalocha, Lanfaro, Siltie and Sankura (Siltie); Decha woreda and Bonga Town (Keffa); Dasenech, Nangatom, Hamer, N/Ari and S/Ari (South Omo), and Alaba Special Woreda. Oromia: Among the flood‐prone woredas in the region are Sebeta Hawas, Becho and Illu (Southwest Shewa); Ejere, Welmera, Ada Berga, Ginde Beret, Chelia and Meta Robi (WestShewa); and Dugda Bora, Adama, Boset and Fentale (East Shewa). Tigray: Alamata and Raya Azebo (Southern Tigray); Atsbi Wonberta and Kilte Awulalo (Eastern Tigray); and Kefta Humera (Western Tigray) are the major flood‐prone woredas in the region. Afar: Zones located in the Awash basin area (Zones 1 and 3) are prone to river flooding while Zones 2, 4 and 5 are vulnerable to flash floods coming from Tigray and Amhara highlands. Flood prone areas in the region include Mille (Zone 1); Abala (Zone 2); Afambo, Awash Fentale, Dubti, Aysaita, Bure Mudayitu, Gewane, Dulecha and Amibara (Zone 3); Gulina and Yallo (Zone 4); and Dalifage, Telalak and Dawe (Zone 5). Somali: Areas along the WabiShebelle, Genale and Dawa Rivers are parts of the flood‐prone areas in the region. These include West Imi, Dolo Bay and Chereti (Afder); Kelafo, Mustahil, Ferfer and East Imi (Gode); and Dolo Ado (Liben). MOST LIKELY SCENARIO Based on the forecasted weather for the coming kiremt season, flooding is expected in the western, northwestern and central parts of the country. In this regard, areas around Lake Tana in Amhara, parts of Gambella, and areas along the Awash basin in Afar are likely to be affected by floods. Moreover, flash floods are anticipated in most prone areas. PREPARDNESS MEASURES TO MITIGATE AND ENSURE TIMELY RESPONSE TO FLOODS In an effort to mitigate the impact of the anticipated floods and facilitate timely response, a Flood Contingency Plan is being prepared to outline expected sectoral requirements, as well as preparedness and response activities. In order to minimize the likely adverse impacts of flooding, appropriate mitigation and preparedness measures should be undertaken. These activities should include dissemination of early warning information to populations at risk, enhancing communication linkages between woreda officials in highland areas that receive heavy rainfall and those downstream that are at risk of flooding, dam management, strengthening flood protection structures, reactivation of regional flood taskforces in areas that are likely to be affected, and preparation of evacuation plans.