Enhancing the effectiveness of flood road gauges with color coding

Abstract

Recent years have witnessed many drowning tragedies on roads, even where flood gauges were equipped to warn drivers about the depth of the flood water. The effectiveness of traditional flood gauges using the digit representation has been questioned. According to the attention–knowledge–compliance three-stage model, we propose that color coding can improve the effect of flood gauges. The present study compared the performance of a prototypical color flood gauge with two types of digit flood gauges in four experiments. Our results revealed a general advantage of color flood gauges over digit flood gauges in all testing conditions (with or without reflection and dynamic or static observation), which was manifested in both a sample of people lacking driving experience and a sample of experienced drivers. Specifically, the mean accuracy of color gauge conditions in the four experiments increased by at least 16%, and the mean response time to the color gauge was shortened by at least 0.8 s compared with the digit gauge. The substantial benefit of color gauges over digit gauges suggests that color coding can be used to improve the effectiveness of flood gauges on flood-prone roads. Because of its low cost, the color coding flood gauge may be useful in the developing world to warn against extreme rainfall.