A New Approach
Green infrastructure offers promising solutions to help remove contaminants from storm water before it reaches our water supply or sewer system. It is designed to mimic nature, filtering stormwater through a rain garden or porous pavement, for example. In recent years, many cities have proposed dealing with sewer overflows with a much greater reliance on green infrastructure instead of traditional gray infrastructure, such as pipes and tunnels.
Blueprint Columbus
The US Environmental Protection Agency recognizes the importance of allowing cities to take into consideration all of the regulatory challenges of complying with the Clean Water Act, and prioritize work to achieve water quality goals more efficiently. They issued a policy encouraging cities to integrate the work needed to comply with both stormwater regulations and elimination of sewer overflows, and strongly promoting the use of green infrastructure to meet these challenges.
Columbus Responds
As a result, the City asked Ohio EPA for permission to delay some of the WWMP projects to allow time to explore whether there is a better alternative; the original plan relied only on tunnels or gray infrastructure.
Specifically, the City wanted to create an Integrated Plan with two main elements:
Remove stormwater from sewers (known as I/I removal or inflow/infiltration). This includes removing I/I from private sources, such as a homeowner’s sewer lateral (the line between the house and the City’s sewer - see larger illustration).
- Route stormwater to green infrastructure for treatment prior to being released. Green infrastructure includes neighborhood improvements in public right-of-ways, such as porous pavement sidewalks, rain gardens and trees. The removal of vacant housing to create pocket parks was also part of the vision.
What are the Benefits?
Potential benefits of this plan are enormous. This plan will significantly improve water quality compared to the gray infrastructure planned in the WWMP. In addition, green infrastructure has been recognized as providing many ancillary benefits, such as air quality improvements, habitat and more. It will also put Columbus ahead of any future stormwater regulations.
There are many other benefits to our community, such as improved property values and helping to stabilize some of our most challenging neighborhoods. These improvements will require perpetual maintenance, which will in turn lead to permanent jobs.
Challenges
While there are many benefits, there are also many challenges presented by this plan. Removing I/I from private property is much more visible and invasive from the homeowner’s perspective. The City may need to: replace/rehab downspouts and gutters, disturb front and back yards, build in the street right-of-way.
The Process
In 2012, Ohio EPA granted the City’s request. The City submitted its integrated plan, known as Blueprint Columbus, and Ohio EPA approved the plan in December, 2015.