Vermont residents’ intentions to adopt green infrastructure

Mar. 29th 2019
rain garden

Poor stormwater management can contribute to waterbody impairment and poor water quality by increasing runoff, flooding, stream bank erosion, and transporting pollutants. Causes of water quality impairment in Vermont include point and non-point source pollution from stormwater runoff from development. Residents and property owners can help with stormwater management by implementing Green Stormwater Infrastructure (GSI). GSI can help improve water quality and storage through mimicking natural ecosystem functions that promote infiltration and treatment. GSI can be integrated with existing stormwater management practices, and can extend beyond water-related benefits to provide temperature and erosion control, pollinator-friendly habitat, and aesthetic, recreational, and cultural benefits. GSI can include rain barrels, infiltration trenches, bioretention, green roofs, and pervious pavement.

A recent study by researchers from the University of Vermont looked at key factors that influence residential intention to adopt specific GSI practices and barriers to this adoption. They conducted a statewide survey of Vermont residents to study barriers to adoption, intention to adopt, and adoption of seven GSI practices. Survey questions also asked whether residents had experienced property or basement flooding, washout and erosion of driveway to house, and if stormwater or flooding was a problem in their neighborhood. Focusing on rain gardens, actively diverting roof runoff, and infiltration trenches, they used spatial analysis to evaluate responses within town, rural, urban, and watershed contexts to better understand how different spatial, social, and physical factors might impact residents’ intention to adopt specific GSI practices.

Overall, approximately 65% of respondents said that they had already adopted or intended to adopt at least one GSI practice. A little more than half of respondents reported no adoption of GSI. Separately, about two-thirds said they were not likely to adopt GSI practices. Diversion of roof runoff was the most frequently reported practice for both adoption and intention to adopt.

Perceived barriers to adoption varied with GSI practice and other contextual factors. A significantly greater number of respondents stated that permeable pavers were too costly compared with other practices. Lack of information was reported to be a barrier to adoption for tree box filters, rain gardens, and permeable pavers more frequently than for infiltration trenches and roof runoff. While fewer households from towns with MS4 permits reported “no need” for adoption of rain gardens, significantly more households reported “not enough space,” “doesn’t look good,” and “against property rules.” A little over half of all households surveyed experienced at least one problem with erosion, washout, flooding or stormwater runoff.

Researchers found that intention to adopt rain gardens, actively diverting roof runoff, and infiltration trenches varied with barriers to adoption, household attributes, and stormwater contexts from the household to watershed scale. For example, infiltration trenches were favored by households experiencing on-site and neighborhood stormwater problems where rain gardens may have been perceived to have benefit at more distant scales. GSI practices like diversion of roof runoff may have important motivational value as a green behavior to households beyond only addressing stormwater.

Since there is no one-size-fits-all GSI solution for stormwater management in a complex social-ecological landscape, it is important to understand how different factors influence adoption of GSI practices. These findings can help inform effective strategies for municipalities and watershed organizations to improve stormwater management among many types of residents. Planners and policy-makers that want to encourage residential adoption of GSI can use this study to develop strategies to address different drivers and barriers to GSI adoption reported by residents.