Like many other aging cities across North America, Detroit faces infrastructure challenges around water. The city’s sewer system is combined to collect rainwater runoff, domestic sewage, and industrial wastewater in the same pipes. When heavy rains occur, the system’s capacity is overwhelmed, and sewage-contaminated waters flood basements and overflow into rivers and ultimately the Great Lakes. These events are called combined sewer overflow discharges, or, CSO’s.
With increased heavy rain and storm events occurring due to climate change, and as a requirement of the EPA’s Clean Water Act to completely eliminate CSO’s, Detroit is under significant pressure to improve its existing stormwater and sewage system. However, the costs of implementing traditional “gray” infrastructure improvements—such as new pipes and larger containment facilities—are only increasing, with current estimates at $1.2 billion.
How The Nature Conservancy is helping
To help reduce or offset these costs, The Nature Conservancy is collaborating with the local government, communities, and private businesses to promote green infrastructure, an engineered design that uses green space and natural plant material to absorb, retain, and slow stormwater runoff. Green infrastructure reduces the amount of water entering a storage facility for treatment, reduces CSO’s, and decreases surface flooding. This leads to improved water quality in adjacent rivers and lakes, as well as attractive green spaces that contribute to neighborhood revitalization by offering recreational areas and beautification opportunities.
In addition to working with the city to integrate green infrastructure into new stormwater management plans, the Conservancy is providing technical assistance in developing a number of new policies that will help to finance and encourage green infrastructure solutions within Detroit. These policies will create the enabling conditions for economic markets and private investment in support of public amenities in a number of innovative ways.