Abstract
Most Latin American demands for drinking water are in or near urban areas. However, population growth and untreated sewage disposal degrade water quality, with negative effects for biodiversity and ecosystem services. Mobilizing society to monitor quality of urban watercourses facilitates training and allows diagnosis that may further help implement mitigation and management strategies. Therefore, our research was conducted in a > 4000 km(2) metropolitan region of high human influence. Urban water body assessments were conducted by 1965 teachers and students and their consistency validated by rigorous scientific methods. The assessments revealed degradation of physical habitat, water quality, or biology in 91% of the evaluated urban stream sites. Increased knowledge concerning environmental stressors and biological responses by local citizens may increase their participation in public policy development and implementation. We conclude that participatory scientific monitoring is a viable way for improving science education, increasing social participation, and improving the ecosystem services provided by urban watercourses.