R/E-22e

Impact/Outcome:

Relevance: Urban stormwater runoff is a growing source of pollution to the Chesapeake Bay, and one of the hardest to combat. Reducing this form of pollution requires that stakeholders be convinced to take action, often at their own expense, to minimize common nutrient pollutants, including nitrogen and phosphorus in fertilizers, from running off their land and washing down storm drains. In order to control stormwater runoff, residents and landowners need to be convinced to install best management practices that help retain and infiltrate stormwater onsite. Many people believe that holding standing water, whether in a garden feature, a rain barrel or pond, will increase the number of mosquitoes in their yards. However, not using these practices results in more stormwater pollution.

Response: Dr. Paul Leisnham of the University of Maryland worked with Maryland Sea Grant Coastal Resilience Fellow Kanoko Maeda and undergraduate assistants to design and distribute a questionnaire that assessed residents' knowledge of and behavior towards urban stormwater and mosquito production in backyard landscapes. They also tested how residents responded to print educational material regarding BMPs and stormwater management. Further, researchers conducted mosquito surveys to test if the most common backyard stormwater structure (disconnected downspouts that drain into gardens rather than sewers) provided habitat for more mosquitoes than backyard containers that collect water (e.g., buckets, birdbaths).

Results: The questionnaire showed that residents who knew more about water resources and BMPs lived in households that used BMPs more often. Residents’ familiarity with BMPs strongly varied with ownership status. Respondents 50 years of age or older were most likely to practice source reduction in disconnected downspouts. Printed educational material did little to change residents’ behavior. These results suggest that careful development and distribution of educational messaging may help residents better understand stormwater management. Mosquito surveys revealed that disconnected downspouts resulted in many fewer mosquitoes than other backyard containers. The research team shared this vital information with households, homeowner associations, and nonprofit groups to dispel the myth that stormwater structures produce mosquitoes and to encourage more residents to use practices to reduce runoff.