Using a diffusion of innovation lens to understand homeowner support for septic system to sewer system conversions.

Water quality impairment linked to household septic systems presents a significant challenge for environmental management professionals given the costs and complexity of encouraging residents to convert to sewer systems. Septic-to-sewer conversion programs may be more effective if they employ innovative techniques such as social marketing to accelerate engagement, but there is a lack of the necessary formative audience research available on which to promote sanitation-related technologies and behaviors using these types of strategies. We used Diffusion of Innovations theory as a lens through which to view support for septic-to-sewer conversion programs, considering perceptions of relative advantage, compatibility, complexity, and observability as factors (i.e., barriers, motivators) in the decision to convert to sewer. We collected data from 518 septic system owners in the state of Florida, USA. Four out of ten respondents indicated there were septic-to-sewer conversion plans in place in their community, and most of these individuals reported the plans were voluntary rather than mandatory. Residents with plans in place had more favorable perceptions than those without such plans and were largely supportive of septic-to-sewer conversion programs. Ordinal regression revealed compatibility and observability were significant predictors of residents' support for septic-to-sewer conversion. When conversion project status variables were added to the final ordinal model, compatibility remained a significant predictor, and completed conversion status also predicted support. Environmental management professionals should consider using characteristics of compatibility and observability to bolster engagement in septic-to-sewer conversion programs, and consider integrating the influences of other communities with completed conversion programs.