There are misconceptions related to stormwater and Green Stormwater Infrastructure (GSI) that we will address in a series of blog postings. This first part addresses stormwater as a larger concern than what falls under environmental protection regulations. Future posts provide facts about GSI best management practices such as pervious surfaces, cold climate functionality, and other topics that present common misconceptions identified by the Vermont Green Infrastructure Roundtable. We hope that these posts will foster greater integration of GSI practices throughout the Vermont landscape.
When you hear the word stormwater, what images come to mind? More than likely, stormwater looks something like this:
For a variety of reasons, we tend to associate stormwater with the urban environment, where precipitation lands on and flows over hard surfaces, picks up pollutants, and is rapidly conveyed though a complex system of drains, pipes, and culverts to local streams or other waterways. However, stormwater is problematic in other parts of the landscape, as well. Farm fields, back roads, rural areas, and even forested lands all generate stormwater to varying degrees, particularly when soils are compacted. So why do we think of stormwater as solely an urban problem?
The 1987 amendments to the federal Clean Water Act (the “Act”) was likely the driving force behind this notion. The original Act focused on managing discharges from “point sources” – discrete conveyances that discharge directly into waterways, such as discharges from industrial plants or sewage treatment facilities. The 1987 amendments expanded the Act to cover urban “non-point sources” of pollution– those diffuse, precipitation-driven pollution sources. These changes that attempt to control pollutants running off of hard surfaces in our larger cities and now our smaller municipalities are necessary to continue to make progress in restoring water quality envisioned by the original Act.
It is important to shift our thinking to more broadly in order to minimize or avoid impacts from stormwater across many landscapes, which is especially important in a rural state such as Vermont. Stormwater also looks like this:
Stormwater is a collective problem: the activities we conduct- from maintaining lawns to home construction- have the potential to contribute pollutants to our waterways.
The pollutants carried by stormwater include nutrients such as phosphorus and nitrogen, sediment, metals, and other chemicals. These pollutants can accumulate in our waterways, causing impacts that can last decades.
Often the best strategy to manage stormwater is not to collect and convey it through a centralized system of pipes and basins, but to “Slow It, Spread It, and Sink it” – strategies that capture, treat, and infiltrate, stormwater at the locations where it is generated. These GSI strategies will help keep stormwater being generated on all lands from polluting downstream waterways.
Here are some resources to help manage stormwater from a number of sources: