Non-market values pose a challenge in decision making. In a contribution to the issue, the study assesses the potential positive impact on residents’ wellbeing of improving the ecological status of water bodies making up the Saarijärvi watercourse in Central Finland, a region with numerous Natura areas. The benefits provided by the aquatic environment and the factors affecting them were assessed using the contingent valuation method (CVM). A split-sample design made it possible to analyse expressed uncertainty with two payment vehicles: in one, the question of uncertainty was included in the willingness-to-pay (WTP) questions (multiple bounded discrete choice, MBDC); in the other, it was queried separately after the payment card (PC) question. Where respondents saw added value in Natura 2000 sites and received new information on water management, they experienced increased wellbeing from improved water quality. Perceived importance of sustainable hydropower and water regulation also figured in a desire to improve the ecological status of waters in the region. The results show that there is a noticeable positive WTP among residents (N = 473) for improved water status and that estimated WTP differs according to uncertainty: mean WTP every year per individual fell in the range EUR 29.70 to EUR 75.50. Improvement of water status and protection of Natura 2000 sites were found to be mutually reinforcing goals. Higher net social benefits could be realized if implementation of the applicable directives were more closely coupled to regional planning.