Creating Urban Flood Vulnerability Assessment tool for ArcMap Software using ModelBuilder and Python

 Over the past 20 years, flood disasters have consisted of 47% of the world's weather-related disasters, which has affected over 2.19 lives in Asia. Likewise, Iran has not been an exception and has always experienced severe damages due to floods. Hence, flood vulnerability assessment (FVA) is vital to mitigate incoming damages. However, the assessments require thorough theoretical knowledge and excellent software skills, limiting widespread usage of such evaluations and increasing financial and temporal requirements. This research aims to create an ArcGIS tool for non-expert ArcMap users to enable them to assess the flood vulnerability without any in-depth knowledge of the software. 

 Firstly, different papers regarding urban FVA were reviewed, and accordingly, the most frequent assessment indicators were identified. Hence, to assign weights to the indicators, the questionnaire method has been employed to ask experts' opinions. Then, indicators were scored, employing the AHP method, using Expert Choice software. Afterward, to create the tool, ModelBuilder was used to design and arrange process flow, and Python language was used to create required ArcMap processing tools that are not built-in in the software. 

 The created tool consists of 56 processes, 15 ArcMap built-in processing tools, and three Python scripted processing tools, namely a logical tool. To run the tool, users must determine six input files, a saving directory, and the name of the case study. The tool saves the outputs in a GDP named after the case study within the user-defined directory. Moreover, to increase the tool's usability for different case studies, the weights of the default indicators' weights can easily be changed in the dialog box. Moreover, the dialog box's language is Persian to provide a user-friendly interface. The tool generates an FVA map and six vulnerability indicator maps to enable users to analyze vulnerability status according to each indicator. The tool is available in TLX format and can be easily added to ArcToolbox. Furthermore, to test the tool's performance, Chaloos city was assessed using it. According to the results, 14 percent of the city, most of which are located proximate to the Chaloos river, is marked as highly vulnerable; 56 percent of the city is marked as vulnerable, and 30 percent of the city is marked as least vulnerable.

 According to the performance test, the processes were completed in nearly nine minutes, and all the outcomes were generated and saved correctly.