Setting Standards for Green Infrastructure Retrofits
CNT is pleased to announce the release of “Upgrade Your Infrastructure”—a new guide for helping cities set and meet annual goals for installing green infrastructure retrofits. The guide is part of a joint initiative between CNT, American Rivers and the Great Lakes and St. Lawrence Cities Initiative, with a grant from U.S. EPA Region 5.
Polluted stormwater is one of the greatest challenges we have to clean drinking water and surface waters in the Unites States. In highly urbanized environments, more than 90% of rainwater may run off impervious surfaces and enter sewer systems. When the combination of sewage and runoff exceeds the stormwater system’s capacity, untreated raw sewage discharges directly to surface streams resulting in Combined Sewer Overflows (CSOs) or Separated Sewer overflows (SSOs). Cities in at least 32 states are affected, with older communities in the Northeast and Great Lakes regions some of the most affected.
Retrofitting cities with green Infrastructure can be a cost-effective, flexible, and environmentally-sound strategy to manage stormwater runoff as a resource and reduce overflows from sewer systems. An increasing number of cities across the Great Lakes and nationally are making multi-million dollar investments in green infrastructure as part of their long term control plans for managing CSOs and, at the same time, reducing local flooding.
However, the current lack of a common methodology means that implementation can sometimes be adhoc, lacking a systematic approach. This new guide illustrates the use of a “Green Infrastructure Portfolio Standard”, which provides a pathway for cities to establish feasible annual retrofit goals, meet these goals with a simple methodology and demonstrate progress over the course of multiple years. The Guide provides examples from pilot retrofit programs in two major Midwest cities, Milwaukee, Wisconsin and Grand Rapids, Michigan that have shown tremendous success using this approach.