Drain Detectives: Lessons Learned from Citizen Science Monitoring of Beach Drains

Abstract

Stormwater drains are common features at city beaches. Stormwater impact from drains is well understood, but the extent and impact of dry-weather flows on water quality and therefore on swimmers is not. Traditional beach monitoring may not be sensitive or frequent enough to assess this risk from drains, and investigation of dry-weather pollution is limited by relatively slow turnaround times for laboratory analysis. This case study describes lessons learned from a trial of citizen science and water quality sensors to monitor drains for dry-weather flows. This involved the use of smartphones and data-collection platforms for community monitoring at signed drains and by trained citizen scientists. Monitoring consisted of photos, observations, and water sampling. A key lesson from the trial was how citizen science can enhance data collected by sensors or by traditional monitoring. Citizen scientists collected data that sensors could not provide on flows, such as size and colour at outlets, and whether flows reached the bay. When combined with sensor data, drains were risk profiled, with higher-risk drains investigated further. Another lesson learned was to adequately resource in-person engagement and communications to motivate and retain citizen scientists. Underestimating resources for engagement translated into less data collected. Community data from signs was a valuable addition, but could have been maximised by simplifying data collection and ensuring signs were close to where observations or photos needed to be taken. The approaches trialled and lessons learned from this project are informative for the design and delivery of similar projects.