Smart growth strategies are a key part of protecting water quality. Compact, mixed-use development means fewer paved and impervious surfaces, which helps reduce environmentally damaging stormwater runoff. Walkable neighborhoods with transportation choices mean fewer vehicle miles traveled, which helps reduce air pollution that falls into rivers as rain. And redeveloping greyfields or brownfields can significantly improve the environmental performance of a building site, while accommodating growth that might otherwise occur in greenfields.

Green infrastructure – including green roofs, rain gardens, tree plantings and permeable pavement – can go even further to protect water quality. Environmental advocates (including Smart Growth America) support rules that would require green infrastructure for new development projects as a way to protect waterways and water quality. But should redevelopment projects be subject to the same regulatory requirements for stormwater as greenfield development?

Because redevelopment already benefits water quality, and because it already faces greater regulatory and site-specific hurdles than greenfield development, many advocates argue no. Several groups, including Smart Growth America, have expressed concern that holding redevelopment projects to the same stormwater standards as greenfield development will raise the cost of these projects and discourage developers from reusing already-developed land. Water quality groups counter that evidence is lacking to support this fear, and that other regulatory factors are more significant in making development decisions.