Approaches to water infrastructure are changing rapidly, with “green” alternatives to traditional stormwater capture and filtration -- such as rain gardens, green roofs, and permeable pavement -- becoming more commonplace, and cities exploring how to reuse vacant or abandoned property for this purpose.

Through case studies of national and local examples, we found that green infrastructure is a viable, realistic option for reducing stormwater runoff, but it is by no means a “silver bullet,” standalone solution. In most cities, it is paired with grey infrastructure to provide a more holistic and beneficial approach to stormwater and water quality management that can lower costs and improve overall capture. Most cities include green infrastructure through an integrated plan or a revised plan developed in response to the escalating costs of EPA Clean Water Act consent decrees. The most common financing tools were bond sales, small grants when available, and storm water fees, almost always paid through utility rate increases. It has become increasingly common to charge stormwater fees based on the amount of impervious surface on a parcel. Although the initial cost of green infrastructure was far less than that of traditional sewer systems, annual maintenance costs must be taken into account to create a more accurate comparison.