Households’ Preference for Payment Vehicles for Freshwater Lake Conservation: Evidence from Vellayani Lake, Kerala

Abstract

Background: Payment mechanisms shape how households consider contributing to freshwater conservation, but a preference for a collection channel is distinct from the amount respondents are willing to pay. This study examined stated preferences for two proposed payment vehicles for Vellayani Lake, Kerala. Methods: A cross-sectional survey of 200 households in Kalliyoor and Venganoor grama panchayats and Thiruvananthapuram Municipal Corporation was conducted in February–March 2026. A pre-tested structured interview schedule elicited socioeconomic information, lake-related perceptions and respondents’ preferences for payment through either a regular water bill or a separate Lake conservation fund. Frequencies, cross-tabulations and Pearson chi-square tests were used to examine unadjusted associations. Results: Payment through the water bill was selected by 129 respondents (64.5%; exact 95% confidence interval [CI]: 57.4–71.1%), and the conservation fund by 71 (35.5%). Among respondents reporting domestic water supply from the lake, 123/169 (72.8%) preferred the water bill, compared with 6/31 (19.4%) of those reporting no lake-derived domestic supply (χ²[1] = 32.65, p < .001; exact conditional odds ratio = 10.99, 95% CI: 4.07–34.91). Gender (p = .025) and age (p = .028) showed unadjusted associations, but neither met a conservative seven-test multiplicity threshold; income, perceived quality, importance of protection and study location showed no statistically significant associations. Conclusion: The water bill was the more frequently selected payment vehicle in this geographically restricted sample, especially among households reporting lake-derived domestic supply. These findings describe an unpriced stated choice and neither estimate willingness-to-pay amounts nor establish practical feasibility or future payment behaviour.