An innovative application of the Contingent Valuation Method in the context of prioritising and assessing investments in improving waterway health is described. The approach provides respondents with a feedback loop that allows for a reassessment of amounts bid across a range of investment categories. It allows respondents the opportunity to consider trade-offs between different categories of waterway health investment and between overall waterway health expenditure and spending on other goods and services. The process also reinforces the consequentiality of the survey, thus encouraging the truthful revelation of preferences, and reduces the risk of part-whole bias. The results provide policy-makers with cost-effective inputs into practical decision making contexts.