This paper reports the results of a large contingent valuation survey to estimate the social benefits of water quality improvements in the watershed. Early results indicate a willingness to pay (WTP) for residential water quality improvements of up to $4.50 per household per month (19% of the average water bill), with a somewhat lower value for preserving the environmental quality of parkland in the watershed. Using a 5% discount rate, this translates into a demand for water quality projects in the region with a capital value of nearly 91100 per household. The narrowness of the estimated range of WTP values, and their similarity to values found in other studies, suggests that our estimates are a reliable measure of the monetary value of social benefits from water quality improvements in the region. The main socio-economic determinants of willingness to pay appear to be household income, number of children, perception of existing water quality, and awareness of environmental issues on the part of survey respondents.