CRWA's Blue Cities Initiative incorporates the design of natural green corridors and infrastructure to help treat stormwater runoff before it enters the Charles and its tributaries, through plant filtration and infiltration into the ground – all while enhancing neighborhoods and connecting existing open spaces.
|Impacts of Urbanization on the Natural Water Cycle, Image source: U.S. Environmental Protection Agency|
Massachusetts receives about 45 inches of precipitation every year. In the natural environment, almost half of this rainfall filters into the ground, and nearly all the rest returns to the sky as water vapor. In cities, we have paved over the ground and cut down many of the trees that turn water into vapor. The result: well over 50 percent of the rain in a typical year quickly becomes polluted stormwater runoff. Developed areas are designed to collect and discard rain quickly, dumping runoff in rivers through storm drains. Bigger storms overwhelm the system, resulting in flooding and, depending on the infrastructure, combined sewer and sanitary sewer overflows.
To make rain once again an asset that replenishes aquifers, and to reduce the pollution from stormwater and the risk of flooding from storm events, CRWA is working to reengineer urban landscapes to function more naturally. By designing natural green corridors and infrastructure that can soak up water and carry it slowly through the city, “Blue Cities” designs also enhance neighborhoods and connect existing open spaces.
CRWA’s work includes partnering with others to build and monitor our demonstration projects, modeling the potential impacts of large scale Blue Cities designs, and training other environmental advocates, local residents, and municipal officials.
Projects within the Blue Cities Initiative fall under three main categories. To learn more about CRWA’s current Blue Cities projects, explore the links below:
Green Infrastructure Demonstration Projects
Science and Technical Analysis