As water flows off of our streets, parking lots, and building rooftops, it picks up all kinds of pollutants like pet waste, sediment, fertilizers, pesticides, oil, and automotive fluids. If it does not evaporate or soak into the ground—nature's "green filter"—and if untreated or poorly treated, the contaminated runoff adversely affects water quality and aquatic life in local streams, the rivers into which they feed, and ultimately the Chesapeake Bay. As more houses, roads, and shopping centers are built, more of this polluted stormwater or runoff makes its way through gutters and storm drains to the nearest stream.
Urban and suburban polluted runoff is a not only a major source of nitrogen pollution to the Bay, it is the only source that is still increasing. It is one of the major reasons that the Bay remains on EPA's "dirty waters" list and is now subject to the Chesapeake Clean Water Blueprint. Though responsible for greater percentages of pollution, agriculture and sewage treatment plants have been making greater progress.
As impervious surfaces channel large quantities of rainwater into streams at high velocity, the runoff wreaks havoc. The flow scours stream banks, destabilizes stream contours and alters depths. It muddies drinking water sources and also carries bacteria, making the treatment and use of such water more expensive.
In the Bay's tributaries, eroded material and dirt from the land become suspended in the water, blanketing aquatic habitat. This sediment keeps sunlight from reaching underwater grasses. As these plants die, the animals that rely on them are imperiled.
And it is not only wildlife that is endangered by stormwater pollution. The state of Maryland, for example, cautions people not to swim in waterways for 48 hours after a heavy rain. Stormwater carrying bacteria has resulted in serious illnesses. In urban and suburban areas where ground surfaces have been hardened and the polluted water has no place to go, local streets and basements often flood, causing repeated and costly damage to homes and businesses.
Better stormwater management is an increasingly necessary—but admittedly expensive—proposition for local governments. CBF is introducing local Bay jurisdictions to a new way of financing green infrastructure for stormwater management, called "impact investment"—and its additional benefits, such as creating local sustainable jobs and more healthy, vibrant communities.
Additional information about stormwater management can be found at the following websites:
From Our Blog
November 9, 2018
We face numerous issues cleaning up the Chesapeake Bay and its rivers and streams. And these issues are interconnected.
October 17, 2018
Garden mud, rain, and rocks were Rafiyqa Muhammad's playground growing up in a south-Harrisburg, PA neighborhood. Today, she's back in that neighborhood, empowering the community through rain gardens and green infrastructure.
October 24, 2018
One of the most ambitious and challenging efforts to reduce the pollutant payload that flows into the Susquehanna, other Commonwealth waterways, and down to the Chesapeake Bay has taken root—the Keystone 10 Million Trees Partnership.
October 3, 2018
At Pennsylvania's Misty Mountain Farm, riparian forest buffers, no-till, and cover crop farming techniques improve soil and water quality, leading to success for business and the Bay.
September 20, 2018
Veteran newspaper photographer John Pavoncello has been eye-to-eye with all kinds of human drama.
31 Jul 2018 Pavoncello Media Productions 00:02:16
This video captures the devastating effects of heavy rains that pummeled Pennsylvania the week of July 23, 2018. These scenes were shot on July 26, the day before the river crested.
09 May 2017 Facebook 00:00:11
The James River in Richmond overflowed its banks after heavy rain washed huge amounts of dirt and pollutants into the current. Clear, clean water turned the color of chocolate milk. Even days after the storm the surge continues as runoff flows 200 miles downstream from the headwaters.
24 Aug 2016 0:01:22
In the summer of 2016, CBF tested bacteria levels in local Pennsylvania streams after heavy rains, finding troubling results.