Valuation of in-stream water quality improvement via fuzzy contingent valuation method

Abstract

Society benefits from rivers in many aspects. To the extent of water resources management, one of the salient issues is that the social benefit of in-stream water quality improvements is often difficult to be quantified for possible cost justification in many water pollution control programs. The difficulties arise from that many service flows of water quality are not channelled through the market system to consumers and producers. With different socio-economic structures, such valuation could be even more challenging when taking river basins with low-income level into account. Recent advances in fuzzy set theory provide a germain insight to viewing the instream water quality as a kind of fuzzy resource due to varying awareness of the quality of life. This paper provides a technical analysis using the fuzzy contingent valuation mothod (FCVM) to value in-stream water quality improvements in terms of three fuzzy resources from aesthetic to recreational, and to ecological aspects. Traditional CVM may allow interest groups or affected parties to join and present a more flexible asset assessment with respect to the prescribed environmental features in the river corridor. Yet the FCVM provides a mechanism that lies in providing a mapping (via fuzzy set theory) from a survey of respondents' valuation of subjective assessments of water quality into objective economic measures in terms of water quality parameters that management can more directly manipulate. With this new tool, the traditional CVM assessment outputs in a well-developed river basin may even lead to derive a simular valuaton function in a form of a regression equation in a developing river basin where the incme level is relatively low. As part of the sustainablity analysis basin wide, a case study in Taiwan showed that such effort may provide supportive information for cost benefit analysis in many water pollution control programs corresponding to different temporal and spatial scales.

Variación temporal y espacial de la calidad de las aguas superficiales en la subcuenca del río Virilla (Costa Rica) entre 2006 y 2010

“…Este procedimiento puede mejorar la comprensión de los diversos procesos y fenómenos involucrados en las matrices ambientales. El FCA evalúa la VLJQLÀFDFLyQ GH FDGD FRPSRQHQWH GH XQ VLVWHPD en términos de pesos predeterminados y disminuye la complejidad (o falta de claridad) por medio de funciones de pertenencia (Chen et al, 2005) que conducen a una mayor sensibilidad analítica en comparación con técnicas de evaluación similares (Guleda et al, 2004). También resuelve los problemas de contorno borroso y controla los efectos de error de seguimiento (Wang, 2002).…”

Sizing an Off-stream Reservoir with Respect to Water Availability, Water Quality, and Biological Integrity

“…Efforts to control water pollution bring substantial direct and indirect benefits, such as ecological and recreational benefits. None of these benefits can be easily quantified and included in the objective function although the treatment costs for water quality improvement can be easily considered in the model formulation [8]. In acknowledging such costs, however, society also benefits from rivers in many aspects.…”

Watershed-based point sources permitting strategy and dynamic permit-trading analysis

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