Whose view do we use? Comparing expert water professional and lay householder perspectives on water-saving behaviours

Applying behavioural science to complex issues, like water demand management, requires behaviour prioritisation for focused program design. This requires tools and data to support decision-making. Some sectors obtain expert-derived data to fill gaps for statistical modelling. However, there is an ongoing debate over use of expert, versus lay, stakeholder perspectives. We extend previous research by examining perceptions held by expert water professionals (n = 44), and lay householder (n = 151) stakeholders, regarding household water-saving behaviours and barriers to participation. We find consistency between expert and lay perceptions on behavioural participation rates and impact on water saving, but less agreement on the effort required for behaviour adoption. Such inconsistency on perceptions of effort could have implications for behaviour selection and intervention design. Our findings suggest that expert-derived data could be used for behaviour prioritisation, but lay input is valuable when everyday (curtailment) or maintenance type water-saving behaviours are under consideration.