Blue-green or grey, how much is the public willing to pay?

Flood reduction infrastructure is a vital aspect of many urban and peri-urban areas. To date, the majority of flood reduction projects use traditional “grey” materials and techniques. However, the use of blue-green infrastructures (BGI) is becoming more popular. This paper explores residents’ preferences for BGI or grey infrastructure projects to reduce flood risk. A discrete choice experiment using a split sample methodology was employed to determine if residents of the Carlingford Lough catchment in Ireland prefer either type of infrastructure to reduce flood risk. A random parameter logit was applied to the data. The results reveal that for the average person, they have a preference for flood risk reduction resulting in a flooding event once every 25 years rather than once every five years. The average respondent also holds a preference for BGI based solutions as opposed to a grey infrastructure solution. However, respondent living in a flood-prone area show no greater preference for a BGI solution.