Planner’s Portfolio: Green Stormwater Infrastructure

The most recent issue in the Planner’s Portfolio series focuses on Green Stormwater Infrastructure.

Green Stormwater Infrastructure (GSI) utilizes landscaped areas to address stormwater runoff. It is a cost-effective approach to manage the impacts of stormwater by directing it away from municipal stormwater systems and into vegetated areas that are designed to infiltrate, or absorb, the runoff.

GSI offers a range of benefits beyond stormwater management and can contribute to the beautification and regreening of an area while also increasing pedestrian safety along roadways. Many public works projects, such as new streetscapes, offer a great opportunity to incorporate GSI into their community as a part of other, ongoing improvement efforts.

For example, in the past, street specifications often required unnecessarily wide streets. More recently, studies show that narrower street widths can accommodate local traffic volumes and parking while also calming traffic. By modifying side streets to be narrower, long-term repaving and maintenance costs are lowered and the reclaimed area provides space to install green stormwater infrastructure. Infiltration gardens in curb bump-outs can manage significant amounts of stormwater runoff along a roadway.

Improving the design of streets and parking lots along Activity Corridors can turn a functional feature into an asset. Aesthetics are improved by adding swales, rain gardens, tree islands, and hardy landscaping to streets and parking lots. If curbs are depressed, pressure on the municipality’s stormwater conveyance system can be reduced by directing water off of the street and into planted areas designed to handle the stormwater.

For more information, check out the Green Stormwater Infrastructure issue or the entire Planner’s Portfolio series.