Abstract：
The State of Kerala has frequently been facing a series of flooding phenomena that have adversely affected its multiple sectoral growths. The floods of 2018 have happened to be one of the most devastating floods that have occurred in the State of Kerala. It was seen that nearly thirteen out of fourteen districts in Kerala were tremendously affected during the 2018 August floods. The worst affected districts during the 2018 floods were Trivandrum, Pathanamthitta, Idukki, Thrissur, Ernakulam, and Kottayam. A sub-region near the Karamana basin located in the Trivandrum district is considered for the present study. The Karamana sub-region is a highly urbanized area that is also more or less prone to intense riverine flooding. The major rivers-Karamana and Killi-along with their respective tributaries, are the water bodies in the study region. Extensive urbanization, along with the overflowing of rivers during monsoon seasons, has paved the way for intense flooding in the region. This, in turn, necessitates developing a flood model for the sub-region. The development of an efficient flood model will aid in understanding the future challenges related to a flooding event in a region. In this study, the flood return probability water levels for the 5-year, 10-year, 25-year, 50-year, 100-year, 250-year, and 500-year were estimated for the Karamana sub-region. Besides, the flood risk zoning for the study area was conducted and elaborated as very high risk, high risk, moderate risk, and low risk for the different areas of the sub-region. Overall, the study can be helpful in identifying the most vulnerable areas to flooding in the Karamana region. By the proper identification of vulnerable areas in the region, proper planning and early warning measures can be devised and carried out by policymakers.
摘要：
喀拉拉邦经常面临一系列洪水现象，对其多个部门的增长产生了不利影响。2018年的洪水恰好是喀拉拉邦发生的最具破坏性的洪水之一。可以看出，在2018年8月的洪水中，喀拉拉邦的14个地区中有近13个受到了极大的影响。2018年洪水期间受灾最严重的地区是Trivandrum，Pathanamthitta,Idukki,Thrissur,Ernakulam,还有Kottayam.本研究考虑了位于Trivandrum地区的Karamana盆地附近的一个子区域。Karamana次区域是一个高度城市化的地区，也或多或少容易发生强烈的河流洪水。主要河流-Karamana和Killi-以及它们各自的支流，是研究区域的水体。广泛的城市化，随着季风季节河流的泛滥，为该地区的严重洪灾铺平了道路。这个,反过来,有必要为该分区开发洪水模型。开发有效的洪水模型将有助于理解与该地区的洪水事件有关的未来挑战。在这项研究中,5年的洪水回归概率水位，10年,25年,50年,100年,250年,估计卡拉马纳次区域为500年。此外,对研究区进行了洪水风险区划，并阐述为非常高风险，高风险,中等风险，次区域不同区域的风险较低。总的来说,这项研究有助于确定卡拉马纳地区最易受洪水影响的地区。通过正确确定该地区的脆弱地区，决策者可以制定和实施适当的计划和预警措施。
