Forget investments in pipes and stormwater holding ponds when it comes to highway and other urban development projects. This is old school thinking.

New school: Think green infrastructure or low-impact designs as the new business opportunities for controlling stormwater runoff.

Instead of relying on pipes and concrete to quickly transport stormwater runoff to a large retention pond, low-impact designs capture the runoff at the source and encourage runoff to filter through the ground. For example: sustainable landscaping, vegetable swales, rain gardens and rain barrels.

That’s a key take-home message from a recent House Water Resources and Environment Subcommittee hearing. Click here for an overview of the committee’s plan.

The panel heard how three cities (Dallas, Milwaukee and Kansas City, MO.) are experimenting with new ways to control stormwater runoff, especially the combined sewer overflows (CSO) created when huge storms flood into municipal sewer systems. These CSO incidents overwhelm treatment capacity and dump untreated sewage into waterways and drinking water supplies.

Dallas mayor, Tom Leppert, was enthusiastic about the potential effectiveness of green infrastructure investments his city has made.  “It’s a myth,” he says, that green infrastructure and low-impact designs are more expensive than traditional engineering solutions. Going green “does not mean it’s automatically more costly,” he told the panel.

However, other mayors raised concerns about the escalating costs of creating massive underground pipes and retention basins needed to isolate stormwater and prevent sewage overflow incidents.

But it was committee chairman, James Oberstar (D-MN), who raised the prospect of creating federal mandates to incorporate low-impact design standards into federally funded projects. Examples of these technologies include:

• green roofs
• downspout disconnection programs
• urban tree planting
• adding green space
• permeable pavements, and
• curb cut-outs.

During the panel’s Q&A session with the mayors, Oberstar was energetic in supporting low-impact design criteria as a much cheaper and more sustainable way to control stormwater runoff. His committee is considering mandating changes in zoning specs to force urban designers and developers to incorporate green infrastructure controls into future highway and other federally supported projects.

Oberstar’s statement is here.

Tags: green infrastructure, green technology, low-impact designs, runoff, stormwater, zoning