Economic Valuation of Canals and Tributaries’ Water Quality Improvement in Bangkok

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Muhammadmunit Phimpraphan
Udomsak Seenprachawong


This study aimed to analyze and estimate willingness to pay (WTP) and its determinants for the waterway quality improvement by using the samples in five districts of the Bangkok area and also to approximate the economic value of such a program. It is also meant to gauge individuals’ WTP for two scales of area development with three waterway improvement levels divided into six scenarios. Scenarios I, II, and III represent levels 1 (slightly), 2 (significantly), and 3 (completely) of improvement for only the nearest canal. Scenarios IV, V, and VI represent levels 1, 2, and 3 of improvement for all canals in the Bangkok area. The Contingent Valuation Method (CVM) has been deployed to value the proposed scenarios. The data set used in the econometric analysis consists of 626 responses for Single-Bounded Dichotomous Choice (SBDC) and Double-Bounded Dichotomous Choice (DBDC) elicitation formats. As a result, the individuals’ socioeconomic characteristics, which significantly affect the WTP, comprise awareness of the waterways’ quality problems, education, and age. The WTP values in scenarios I to VI, estimated with the SBDC model, are approximately 71.05, 71.51, 121.31, 73.43, 125.45, and 198.05 baht per month per household. However, such values, estimated with the DBDC model, are approximately 75.91, 96.93, 145.39, 111.78, 153.54, and 198.29 baht per month per household. The DBDC model gave a smaller variance of estimated WTP and complied more with the scope test. The total economic value of the improvement program estimated from the individuals’ WTP is approximately 1,093.11 Million baht annually.

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How to Cite
Phimpraphan, M., & Seenprachawong, U. (2024). Economic Valuation of Canals and Tributaries’ Water Quality Improvement in Bangkok. Connexion: Journal of Humanities and Social Sciences, 13(1), 34–53. Retrieved from
Research article


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