Subsidence sinkholes in karst terrain are a common geological hazard, which can lead to natural disasters in the natural and built environment. Groundwater ingress is the main factor leading to subsidence. Previous research has focused on the qualitative analysis of the influence of groundwater, although limited research into critical triggering conditions of groundwater has been undertaken quantitatively. Water seepage into soil is the starting condition in the development of subsidence sinkholes. This paper focuses on testing the anti-permeability strength as the critical triggering condition in the formation of subsidence sinkholes, and develops a design and methodology to test its value quantitatively. The methodology is applied in an industrial park of Guilin, China, to assess the probability of forming subsidence sinkholes. Results indicate that there is a low susceptibility to the formation of subsidence sinkholes under current conditions in the ground-truth investigation.