Abstract
Benefits of water quality improvement in eutrophicated Osaka Bay should be judged in terms of environmental values. In this study, the authors quantify TEV (Total Economic Value) of water quality improvement that is based on citizens' willingness-to-pay shown by questionnaire. The citizens which expect water quality improvement in the future, express their high valuation of water-related environmental amenity. Non-user benefits, which is constituted of option value, bequest value, vicarious value and existence value, is four times as large as user benefits. Therefore, non-user benefits should be added to user benefits in TEV. The estimated TEV of environmental services of bay water is about 500 million dollars per year in the osaka bay area, which corresponds to 0.11% of the annual gross domestic product in metropolitan Osaka with 17 million population.
