본 연구에서는 과거 홍수로 인해 내수침수피해를 입은바 있는 서천군 장항읍 장항지구를 대상으로 도시유출모형인 SWMM모형을 적용하고, 조위영향을 고려한 침수방지대책을 수행하였다.
도시유출모형인 SWMM 모형의 구성 Runoff block, Transport block, Extran block에 대한 내용 및 기본이론을 소개하였으며, 대상유역에 대한 배수시설 현황 및 수리·수문 조사, 과거 침수피해 현황 조사를 실시하였다.
대상지구 침수대책은 우수관로의 통수능 부족과 외수위 영향에 의해 단일 시설물만으로 내수침수 해소가 불가능하므로, 개별시설물과 조합시설물의 평가를 통해 상습침수지역의 침수해소방안을 도출하였다.
Alternative Abstract
Recently, in Korea damages to life and properties are increasing due to local torrential rainfall over the years and as a result of global climate variability. Especially, this phenomenon causes serious damages in those areas changing to urbanization due to more vulnerable conditions
This study analyzing flood inundation based on two-dimensional urban flood runoff model (XP-SWMM Model) focusing on coastal urban areas. In future, the outcome of this study are expected to be utilized effectively in watershed management and policy establishment for the water resources manager.
After analyzing the localized torrential rainfall of August 2012, the areas subjected to flood was found to be 4.8ha employing the XP-SWMM Model with an overflow volume of 17,056㎥, and it was similar to the existing actual inundated area. The most affected areas were those with low flat geographical features and which are lacking in proper drainage facilities. These areas were also among those that are vulnerable to tidal waves and their consequences.
The capacity of existing conduits were reviewed after dividing into the natural release and those influenced by the tide level. The studied area was found flooded with only natural release even without considering the outside tide level effects. Further, it is evident that after considering the tide level, the flooded areas was increased in the study area(30,030㎥(131%)) compared to natural release inundated damage.
Flood prevention measures should be set up based on combined effects of natural releases and the tidal effects to increase the drainage capacity. As a result, optimistic flood prevention measures suggested for Janghang Zone 1, 2 are water detention and Gate pumping system and for Janghang Zone 3 is water detention, Gate pumping, and a specific drainage system.