Flood Vulnerability Assessments and Scenario Landscape Planning of Communities Around Industrial Estates in Ayutthaya

Abstract

Thailand is vulnerable to severe flooding; for example, the 2011 flood affected 13 million people and caused significant socioeconomic damage. Because of a possible 100-year return period and other climate change effects, in 2012, industrial estates in Ayutthaya, such as the Rojana Ayutthaya Industrial Park, developed flood protection systems by raising the flood walls to around six meters above the mean sea level (MSL); however, the surrounding areas do not have comprehensive plans. This study analyzes the physical landscapes within a radius of two kilometers around Ayutthaya's industrial estate to assess flood vulnerability, after which we develop adaptation strategies based on community input for vulnerable areas. The topography and footprint maps are analyzed to identify the flood scenarios. To compare the urban and agricultural area differences, the highest 2011 water level of 5.30 meters above MSL was applied to identify two scenarios for moderate and extreme flood areas. Alternative mitigation solutions for both scenarios were discussed in a community focus group, which decided that the engineering resistance concept would best prevent moderate flooding because of the current flood protection levee improvements around the study areas. However, while the landscape resilience concept was seen by the communities as a more sustainable solution, it was considered difficult to implement due to land ownership issues. The moderate and severe flood mitigations are conceptually a resistance to resilience shift in flood control approaches, which could be adopted by other regions or countries that suffer similar problems.