We hear a lot about infrastructure these days as our government debates economic stimulus spending. Green infrastructure is smart! It can entail green parking, green roofs, bioswales, rain gardens, rainwater harvesting, urban tree canopies, and permeable pavements. “Green infrastructure” is a catch-all term that refers to using plant-based infrastructure to better manage weather impacts. And during heat waves, these can keep buildings cooler, trees can cool street scapes, and rain gardens can treat stormwater.
Studies have found that green infrastructure typically has a significant, positive return on investment.
- For instance, one study notes that green infrastructure costs “$13 to $65 annually” to plant trees, but that the benefits range from $31 to $89 per tree.”
- According to another study, “the Philadelphia Water Department estimates that it can afford to spend up to $260,000 per acre on green infrastructure projects (green roofs, bioswales, rain gardens, etc.) rather than continue to treat the stormwater that otherwise would flow from these project areas into their combined sanitary/stormwater system.”
- A large part of the cost savings stems from the fact that green infrastructure helps combat combined highly unsanitary combined sewage overflows.