Preserving water quality, which has at least four of the ten characteristics of a "wicked problem", is fundamental for economic development, ecosystems function, and human wellbeing. Consequently, identifying suitable public policies or technological solutions that can maintain or restore affected ecosystems, especially in river catchments, is a huge challenge. Understanding diverse stakeholder perspectives on important aquatic ecosystem services is critical to improving water governance and quality. This study uses the Q-methodology to identify and analyze perspectives about aquatic ecosystem services in the Olifants River catchment, one of the most important and polluted in South Africa, across six diverse stakeholder groups competing for its limited water resources. The Q methodology is a semi-qualitative methodology that can systematically recover detailed views of the subjective perceptions diverse stakeholder groups hold on a given topic. Our results suggest existence of three significant and conflicting perspectives. The "conservationists" prioritize regulation and supporting services, the "water users" give highest priority to water for domestic and other private uses, while the "planners" rank mastering the environment for societal benefits highest. Equally importantly, our results suggest the possibility of solutions that can deliver services ranked highly by some stakeholders without compromising the welfare of others who hold neutral perspectives towards them.