The Riverfly Partnership, launched in 2004, is a UK network of organisations and individuals working to protect river habitats and macroinvertebrate communities. The Riverfly Partnership's Anglers' Riverfly Monitoring Initiative (ARMI), launched in 2007, supports citizen science volunteers to monitor macroinvertebrates in their local rivers. In Manchester and surrounding areas, ARMI monitoring began in 2011 with volunteers from a fishing club active across the Irwell catchment. Whilst there has been mixed success establishing a robust long-term monitoring program, volunteers investigate issues raised by the local community and data provide a baseline against which river pollution events can be compared. For example, in April 2017 citizen scientists responding to a report of dead crayfish by an angler identified a pollution incident resulting in a catastrophic loss of macroinvertebrates along a 19 km reach of the River Irwell. Recognizing the limitations of the ARMI methodology for urban and degraded rivers nationwide led to the development of the Urban Riverfly index through the Riverfly Partnership so that citizen scientists can more effectively contribute to the work of government agencies mitigating urban river pollution. Citizen science has importantly been a catalyst for public engagement and environmental projects which should encourage wider public participation in river catchment management.