ارزيابي روش سريع آب‌گرفتگي شهري مبتني بر عوارض زمين: عمق، سطح و حجم آب‌گرفتگي

Assessment Rapid Urban Inundation Method Based on Urban Terrain: Depth, surface and volume of inundation

ﻣﺪلﻫﺎي رﮔﺒﺎر-آﺑﮕﺮﻓﺘﮕﯽ ﻣﺒﺘﻨﯽ ﺑﺮ ﻫﯿﺪروﻟﻮژي و ﻫﯿﺪرودﯾﻨﺎﻣﯿﮏ ﺑﻪ ﺗﻌﺪاد زﯾﺎدي داده )ﺟﺰﺋﯿﺎت زﻣﯿﻦ، ﺳﯿﺴﺘﻢ ﻓﺎﺿﻼب و داده ﮐﺎرﺑﺮي اراﺿﯽ( ﻧﯿﺎزﻣﻨﺪ اﺳﺖ. در اﯾﻦ ﻣﻘﺎﻟﻪ ﺑﻪ ﻣﻨﻈﻮر ﺗﻌﯿﯿﻦ ﺳﺮﯾﻊ وﺿﻌﯿﺖ آﺑﮕﺮﻓﺘﮕﯽ ﺗﻨﻬﺎ ﺑﺎ ﭼﻨﺪ داده ورودي و ﻣﻌﻤﻮﻻ در دﺳﺘﺮس، ﯾﮏ روش ﺷﺒﯿﻪﺳﺎزي رﮔﺒﺎر- آﺑﮕﺮﻓﺘﮕﯽ ﺷﻬﺮي )USISM( ﻣﺒﺘﻨﯽ ﺑﺮ ﺳﺎﻣﺎﻧﻪ اﻃﻼﻋﺎت ﺟﻐﺮاﻓﯿﺎﯾﯽ اراﺋﻪ ﺷﺪه اﺳﺖ. روش USISM ﯾﮏ ﻧﻮع ﻣﺪل ﻫﯿﺪروﻟﻮژﯾﮑﯽ ﺗﻮزﯾﻌﯽ ﺳﺎده ﺷﺪه ﺑﺮ اﺳﺎس ﻣﺪل ارﺗﻔﺎع رﻗﻮﻣﯽ ﻣﯽﺑﺎﺷﺪ. در اﯾﻦ روش، ﻓﺮورﻓﺘﮕﯽ ﻫﺎ در زﻣﯿﻦ ﺑﻪ ﻋﻨﻮان ﺳﻄﻮح اﺻﻠﯽ آﺑﮕﺮﻓﺘﮕﯽ در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﻣﯽﺷﻮﻧﺪ. ﻣﻘﺪار آﺑﯽ ﮐﻪ ﻣﯽﺗﻮاﻧﺪ در ﻫﺮ ﻓﺮورﻓﺘﮕﯽ ذﺧﯿﺮه ﺷﻮد ﺗﻮزﯾﻊ ﻧﻬﺎﯾﯽ آﺑﮕﺮﻓﺘﮕﯽ را ﻧﺸﺎن ﻣﯽدﻫﺪ. ﺳﻄﺢ رواﻧﺎب ﺣﻮﺿﻪ و ﺣﺪاﮐﺜﺮ ﺣﺠﻢ ذﺧﯿﺮه ﺑﺮاي ﻫﺮ ﻓﺮورﻓﺘﮕﯽ و ﺟﻬﺖ ﺟﺮﯾﺎن ﺑﯿﻦ اﯾﻦ ﻓﺮورﻓﺘﮕﯽ ﻫﺎ ﻫﻤﻪ در ﺷﺒﯿﻪﺳﺎزي ﻧﻬﺎﯾﯽ آﺑﮕﺮﻓﺘﮕﯽ در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪهاﻧﺪ. روش ﺳﺎزﻣﺎن ﺣﻔﺎﻇﺖ ﺧﺎك اﻣﺮﯾﮑﺎ ﺑﺮاي ﻣﺤﺎﺳﺒﻪ رواﻧﺎب رﮔﺒﺎر، و ﯾﮏ ﻣﻌﺎدﻟﻪ ﺑﯿﻼنآﺑﯽ ﺑﺮاي ﻣﺤﺎﺳﺒﻪ ذﺧﯿﺮه آب در ﻫﺮ ﻓﺮورﻓﺘﮕﯽ اﺳﺘﻔﺎده ﺷﺪه اﺳﺖ. ﻧﺘﯿﺠﻪ ﻧﺸﺎن ﻣﯽ دﻫﺪ ﮐﻪ در ﻫﺮ 4 واﻗﻌﻪ رﮔﺒﺎري ، ﻣﺘﻮﺳﻂ ﺧﻄﺎﻫﺎي ﻧﺴﺒﯽ ﻋﻤﻖ در ﮐﻠﯿﻪ ﻣﮑﺎنﻫﺎي آبﮔﯿﺮ ﮐﻤﺘﺮ از 20 ﻣﯽﺑﺎﺷﺪ، در ﺣﺎﻟﯽﮐﻪ ﻣﺘﻮﺳﻂ ﺧﻄﺎﻫﺎي ﻧﺴﺒﯽ ﻣﺴﺎﺣﺖ و ﺣﺠﻢ ﺑﯿﺶ از60 % ﻫﻢ ﻣﯽ ﺑﺎﺷﺪ ﻟﺬا روش USISM ﻗﺎﺑﻠﯿﺖ ﺑﺎﻻﺗﺮي در ﺷﺒﯿﻪﺳﺎزي ﻋﻤﻖ ﻧﻬﺎﯾﯽ آبﮔﺮﻓﺘﮕﯽ ﻧﺴﺒﺖ ﺑﻪ ﺳﻄﺢ و ﺣﺠﻢ آبﮔﺮﻓﺘﮕﯽ دارد ﻫﻤﭽﻨﯿﻦ روش USISMﻣﯽﺗﻮاﻧﺪ ﻣﮑﺎن ﻫﺎي ﻧﻬﺎﯾﯽ آﺑﮕﺮﻓﺘﮕﯽ در ﻣﻨﻄﻘﻪ ﺷﻬﺮي را ﺗﻌﯿﯿﻦ و ﻋﻤﻖ و ﺳﻄﺢ آﺑﮕﺮﻓﺘﮕﯽ را ﺑﻪ ﺳﺮﻋﺖ ﻣﺤﺎﺳﺒﻪ ﻧﻤﺎﯾﺪ و ﻟﺬا در ﻣﺪﯾﺮﯾﺖ ﺑﺤﺮان ﺷﻬﺮي ﻧﻘﺶ ﺑﺴﺰاﯾﯽ را اﯾﻔﺎ ﮐﻨﺪ .

Storm-inundation models based on hydrology and hydrodynamics require a large amount of input data (detailed terrain, sewer system and land use data). In this paper, in order to determine inundation conditions quickly with only a few usually available input data is proposed an urban storm-inundation simulation method (USISM) based on Geographic Information System (GIS). The USISM is a simplified method of distributed hydrological model based on DEM, in this method depressions in terrain are regarded as the basic inundated area. The amount of water that can be stored in a depression indicates the final inundation distribution. The runoff and maximum storage volume for each depression and the flow direction between these depressions are all considered in the final inundation simulation. The SCS method is used to calculate storm runoff and a water balance equation is used to calculate the water storage in each depression. The result shows that in all four-storm event, the average relative depth errors of depth in all inundation sites are less than 20%, while the average relative errors of area and volume are more than 60% Therefore, the USISM method has a higher ability to simulate the final depth of inundation than the surface and volume of inundation. The result reveals that the USISM method could find the inundation locations in the Damghan Urban Watershed and calculate inundation depth and area quickly and therefore display a significant role in the management of the urban crisis.