Flood risk analysis: causes and landscape based mitigation strategies in Dire Dawa city, Ethiopia
Tóm tắt
In flood prone areas, understanding flood causing factors, assessing the flood induced risks and adopting landscape based mitigation strategies can increase the knowledge, awareness and individual initiatives to protect themselves and their properties using appropriate flood management measures before and during flood events. Dire Dawa city is located in the foothill of southern mountains from where rivers crossing the city are originated. The multidimensional causes of flood hazard and limited landscape based mitigation strategies in the study area have worsen the impacts of flooding. This study was conducted in the Dire Dawa city watershed with the aims of assessing flood causing factors and to propose landscape based flood mitigation strategies. To meet the intended objectives, the study employed the collection of both primary and secondary data. The primary data were collected from 110 households located in flood vulnerable villages. Moreover, the secondary data were collected from the Ethiopian Meteorology Agency, land use map of Dire Dawa city administration and government reports. Rainfall index method and descriptive statistics were used for analysis of primary data. The former was used to check the effect of intense rainfall and flood risk in terms of different duration yearly, monthly, daily and hourly basis, while the latter was used for identification of various factors precipitating flood risks of the study area. The analysis of secondary data employed morphometric analysis so as to identify flood susceptible sub-watersheds. Findings of the study indicated that flood risk in the study area has resulted from multiple factors such as intense rainfall, topography, encroachment to the river banks, institutional problems and aggravating factors resulted from power interruption during heavy rain and regime changes. More importantly, flood risk of the study area was found to be sensitive to hourly variation of rainfall distributions and varies on the location of the sub-watersheds. Following that, flood susceptibility of sub-watershed was ranked based on linear and shape morphometric parameters where higher values of linear and lower values of shape parameters were attributed to high flooding risk. Based on the prioritization of sub-watersheds’ susceptibility to flood risk through morphometric analysis, sub-watershed 5 and 18 were identified as the most flood risk susceptible watersheds demanding urgent landscape-based conservation measures. To this end suitable sites and sustainable water conservation structures are identified across the watersheds. Check dams, terracing, nala bunds, percolation tanks and storage tanks were proposed for different locations across the watershed as effective landscape-based flood risk mitigation strategies. The overall results of the study shows that managing the root causes of flooding at the upper catchments and adopting recommended proposed water conservation structures at proposed site helps to sustainably curb flood induced risks of Dire Dawa city.
Tài liệu tham khảo
Abrahams, A.D. 1984. Channel networks: A geomorphological perspective. Water Resource Research 20: 161–168.
Agarwal, R., P.K. Garg, and R.D. Garg. 2013. Remote sensing and GIS based approach for identification of artificial recharge sites. Water Resource Management 27 (7): 2671–2689. https://doi.org/10.1007/s11269-013-0310-7.
Agbola, S.B., O. Ajayi, J.O. Taiwo, and W.B. Wahab. 2012. The august 2011 flood in Ibadan, Nigeria: Anthropogenic causes and consequences. International Journal of Disaster Risk Science 3 (4): 207–217.
Al-Adamat, R., S. AlAyyash, H. Al-Amoush, O. Al-Meshan, Z. Rawajfih, A. Shdeifat, and M. Al-Farajat. 2012. The combination of indigenous knowledge and geo-informatics for water harvesting sitting in the Jordanian Badia. Journal of Geographic Information System 4: 366–376.
Alemayehu, D. 2007. Assessment of flood risk in Dire Dawa town, Eastern Ethiopia, Using GIS. Ethiopia: Unpublished Msc. Thesis, Addis Ababa University.
Ali, U., and A. Ahmad. 2014. Analysis of drainage morphometry and watershed prioritization of Romushi - Sasar catchment, Kashmir Valley, India using remote sensing and GIS technology. International Journal of Advanced Research 2 (12): 5–23.
Altaf, F., G. Meraj, and S. Romshoo. 2013. Morphometric analysis to infer hydrological behavior of Lidder watershed, Western Himalaya, India. Geography Journal: 13, 1–13,14.
Ammar, Adham, Michel Riksen, Mohamed Ouessar, and Coen Ritsema. 2016. Identification of suitable sites for rainwater harvesting structures in arid and semi-arid regions: A review. International Soil and Water Conservation Research 4 (2): 108–120 https://doi.org/10.1016/j.iswcr.2016.03.001.
Bouwer, L.M. 2013. Projections of future extreme weather losses under changes in climate and exposure. Risk Analysis 33: 915–930.
Chandniha, S.K., and M.L. Kansal. 2017. Prioritization of sub-watersheds based on morphometric analysis using geospatial technique in Piperiya watershed, India. Applied Water Science 7 (1): 329–338.
Chow, V.T. 1964. Handbook of applied hydrology: A compendium of water-resources technology, 1495. New York: McGraw-Hill.
Chowdary, V.M., D. Chakraborthy, A. Jeyaram, Y.V.N.K. Murthy, J.R. Sharma, and V.K. Dadhwal. 2013. Multi-criteria decision making approach for watershed prioritization using analytic hierarchy process technique and GIS. Water Resources Management 27 (10): 3555–3571. https://doi.org/10.1007/s11269-013-0364-6.
Costa, J.E. 1987. Hydraulics and basin morphometry of the largest flash floods in the conterminous United States. Journal of Hydrology 93 (34): 313–338.
CSA. 2013. Population Projection of Ethiopia for all Regions at Woreda level from 2014–2017, Central Statistical Authority, Addis Ababa.
Dar, R.A., R. Chandra, and S.A. Romshoo. 2013. Morphotectonic and Lithostratigraphic analysis of Intermontane Karewa basin of Kashmir Himalayas, India. Journal of Mountain Science 10 (1): 1–15.
Dawod, G.M., M.N. Mirza, and K.A. Al-Ghamdi. 2012. GIS-based estimation of flood hazard impacts on road network in Makkah city, Saudi Arabia. Environmental Earth Science 67 (8): 2205–2215 https://doi.org/10.1007/s12665-012-1660-9.
Doocy S, Daniels A, Murray S, Kirsch TD.2013. The human impact of floods: A historical review of events 1980-2009 and systematic literature review. PLOS currents disasters. Edition 1.
Eze, E.B., and J. Efiong. 2010. Morphometric parameters of the Calabar river basin: Implication for hydrologic processes. Journal of Geography and Geology 2 (1): 18–26.
FAO. 1998. Irrigation and Drainage, No 56, FAO, Rome, Italy.
FAO. 2003. Land and water digital media series, 26. Training course on RWH (CDROM). Planning of water harvesting schemes, unit 22. Rome: Food and Agriculture Organization of the United Nations, FAO.
Farhan, Y. 2017. Morphometric assessment of Wadi Wala watershed, southern Jordan using ASTER (DEM) and GIS. Journal of Geographic Information System 9: 158–190.
Farhan, Y., and O. Anaba. 2016. Remote sensing and GIS approach for prioritization of Wadi Shueib mini-watersheds (Central Jordan) based on morphometric and soil erosion susceptibility analysis. Journal of Geographical Information System 8: 1–19.
Farhan, Y., and A. Ayed. 2017. Assessment of flash-flood Hazard in arid watersheds of Jordan. Journal of Geographic Information System 9: 717–751.
Funk, T. 2006. Heavy convective rainfall forecasting: A look at elevated convection, propagation and precipitation efficiency. In In proceedings of the 10th severe storm and Doppler radar conference. Des Moines, IA: National Weather Association.
Gardiner, V. 1990. Drainage basin morphometry. In Geomorphological techniques, ed. A.S. Goudie, 71–81. London: Unwin Hyman.
Girma, M., and V. Bhole. 2015. Morphometric characteristics and the relation of stream orders to hydraulic parameters of river Goro: An Ephemeral River in Dire-Dawa, Ethiopia. Universal Journal of Geoscience 3 (1): 13–27.
Gupta, A., and R. Ahmad. 1999. Geomorphology and the UrbanTropics: Building an Interface between research and usage. Geomorphology 31 (1–4): 133–149.
Horton, R.E. 1932. Drainage basin characteristics. Transactions of American Geophysical Union 13: 350–361.
Horton, R.E. 1945. Erosional development of streams and their drainage basins: Hydro-physical approach to quantitative morphology. Geological Society of American Bulletin 5: 275–370.
International Strategy for Disaster Reduction (ISDR). 2008. Disaster risk reduction strategies and risk management practices: Critical elements for adaptation to climate change. In Submission to the UNFCCC Adhoc working group on long term cooperative action.
Jonkman, S.N. 2005. Global perspectives on loss of human life caused by floods. Natural Hazards 34 (2): 151–175.
Jung, J.W., H.N. Park, D.H. Choi, S.S. Baek, K.S. Yoon, W.J. Baek, J.A. Beam, and B.J. Lim. 2013. Analysis of first flush of recreation park and removal rate according to rainfall-runoff storage depth. Journal of Korean Society on Water Environment 29 (5): 648–655.
Kanth, T.A., and Z. Hassan. 2012. Morphometric analysis and prioritization of watersheds for soil and water resources Management in Water Catchment using geo spatial tools. International Journal of Geology, Earth and Environmental Sciences 2: 30–41.
Krishnamurthy, J., G. Srinivas, V. Jayaram, and M.G. Chandrasekhar. 1996. Influence of rock types and structures in the development of drainage networks in typical hard rock terrain. ITC Journal 3 (4): 252–259.
Kumar, R., S. Kumar, A.K. Lohani, R.K. Nema, and R.D. Singh. 2000. Evaluation of geomorphological characteristics of a catchment using GIS. GIS India 9 (3): 13–17.
Kumar, T., A.K. Gautam, and D.C. Jhariya. 2016. Multi-criteria decision analysis for planning and management of groundwater resources in Balod District, India. Environmental Earth Science 75 (649) https://doi.org/10.1007/s12665-016-5462-3.
Langbein, W.B. 1947. Topographic characteristics of drainage basins. U.S Geological Survey Water Supply Paper 986: 157–159.
Lenderink, G., and E. van Meijgaard. 2008. Increase in hourly precipitation extremes beyond expectations from temperature changes. Nature Geoscience 1: 511–514.
Miller, J.D., and M. Hutchins. 2017. The impacts of urbanization and climate change on urban flooding and urban water quality: A review of the evidence concerning the United Kingdom. Journal of Hydrology and Regional Studies 12: 345–362 https://doi.org/10.1016/j.ejrh.
Miller VC.1953. A quantitative geomorphic study of drainage basin characteristics in the Clinch Mountain area, Varginia and Tennessee, project NR 389042, tech Rept 3., Columbia University, department of Geology. 1–30.
Moglen, G.E., E.A. Eltahir, and R.L. Bras. 1998. On the sensitivity of drainage density to climate change. Water Resource Research 34: 855–862.
Nijland, H.J. 2005. Sustainable development of floodplains (SDF) project. Journal of Environmental Science and Policy 8: 245–252.
Nyamathi, S.J., Kavitha, B. 2013. Morphometric analysis and runoff estimation of a catchment using different data set”, Research and Reviews: Journal of Engineering and Technology. Volume 2, No 13, July – September, 2013, pp. 87–94.
Ologunorisa, T.E., and A. Adejumo. 2005. Public perception of flood Hazard in the Niger Delta, Nigeria. The Environmentalist 25 (1): 39–45.
Ozdemir, H., and D. Bird. 2009. Evaluation of morphometric parameters of drainage networks derived from topographic maps and DEM in point of floods. Environmental Geology 56: 1405–1415.
Panhalkar, S., and B. Gowtham. 2011. Site suitability analysis for ground water recharge in Dudhaganga Bain, India, a geo-informatics approach. National Journal of chembiosis 2 (1): 1–13.
Prinz, D., and A. Singh. 2000. Technological Potential for Improvements of Water Harvesting. Germeny: Prepared for Thematic Review IV.2: Assessment of Irrigation Options http://www.dams.org/.
Ramaiah, S.N., G.S. Gopalakrishna, S. Srinivasa, and Md Najeeb. 2012. Morphometric analysis of sub-basins in and around Malur Taluk, Kolar District, Karanataka using remote sensing and GIS techniques. Journal of Nature Environment and Pollution Technology 11: 89–94.
Ratnam, K.N., Y.K. Srivastava, and V.R. Venkateswara. 2005. Check dam positioning by prioritization of micro-watersheds using SYI model and morphometric analysis -remote sensing and GIS perspective. Journal of the Indian Society of Remote Sensing 33: 25–38.
Rudraiah, M., S. Govindaiah, and V.S. Srinivas. 2008. Morphometry using remote sensing and GIS techniques in the sub-basins of Kagna river basin, Gulburga district, Karnataka, India. Journal of Indian Society of Remote Sensing 36: 358.
Schumm, S.A. 1956. Evolution of drainage systems and slopes in badlands at Perth Amboy, New Jersey. Geological Society of American Bulletin 67: 597–646.
Shang, J., and P. Wilson. 2009. Watershed urbanization and changing flood behavior across the Los Angeles metropolitan region. Natural Hazards 48: 41–57.
Singh, P., A. Gupta, and M. Singh. 2014. Hydrological inferences from watershed analysis for water resource management using remote sensing and GIS techniques. Egyptian Journal of Remote Sensing Space Science 17: 111–121.
Singh, S., and M.C. Singh. 1997. Morphometric analysis of Kanhar river basin. National Geographical Journal of India 1: 31–43.
Smith, K.G. 1950. Standards for grading textures of erosional topography. American Journal of Sciences 248: 655–668.
Strahler, A.N. 1964a. Quantitative geomorphology of drainage basins and channel networks. In Handbook of applied hydrology, ed. V.T. Chow, 439–476. New York: McGraw-Hill.
Strahler, A.N. 1964b. Quantitative geomorphology of drainage basins and channel networks section 4–2, handbook of applied hydrology, Ven Te chow, 4–35. New York: McGraw-Hill.
Verstappen, H.T. 1995. Aerospace technology and natural disaster reduction. In Natural hazards: Monitoring and assessment using remote sensing technique, ed. R.P. Singh and R. Furrer, 3–15. Oxford: Pergamon Press.
Yonas, T.A. 2015. Increased frequency of flash floods in Dire Dawa, Ethiopia: Change in rainfall intensity or human impact? Natural Hazards 76 (2): 1373–1394.
Youssef, A.M., B. Pradhan, and A.M. Hassan. 2011. Flash flood risk estimation along the St. Katherine road, southern Sinai, Egypt using GIS based morphometry and satellite imagery. Environ Earth Science 62: 611–623 https://doi.org/10.1007/s12665-010-0551-1.
Youssef, A.M., B.D. Pradhan, A.F. Gaber, and M.F. Buchroithner. 2009. Geomorphological hazard analysis along the Egyptian Red Sea coast between Safaga and Quseir. Natural Hazards and Earth System Sciences 9 (3): 751.
Youssef, A.M., S.A. Sefry, B. Pradhan, and A.E. Alfadail. 2016. Analysis on causes of flash flood in Jeddah city (Kingdom of Saudi Arabia) of 2009 and 2011 using multi-sensor remote sensing data and GIS. Geomatics, Natural Hazards and Risk 7 (3): 1018–1042. https://doi.org/10.1080/19475705.2015.1012750.