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As we develop our cities and towns, we replace forests and meadows with buildings and pavement. And now when it rains, the water often called runoff or stormwater runs off roofs and driveways into the street. Runoff picks up fertilizer, oil, pesticides, dirt, bacteria and other pollutants as it makes its way through storm drains and ditches - untreated - to our streams, rivers, lakes and the ocean.
Polluted runoff is one of the greatest threats to clean water in the U. When we take action to soak up the rain, we keep rain closer to where it falls and reduce the runoff from our roofs, driveways, and parking lots.
Reducing runoff can help prevent water pollution, reduce flooding, and protect our precious drinking water resources. When we soak up the rain, we also help beautify our neighborhoods and bring many other benefits to our communities:. 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 miles downstream from the headwaters. Stay up to date about the Bay! Sign Up. And it offers steps that local, state, and federal governments can take to reduce pollution and achieve clean water for local streams, rivers, and the Chesapeake Bay. Download it today [pdf]. Your donation helps the Chesapeake Bay Foundation maintain our momentum toward a restored Bay, rivers, and streams for today and generations to come.
Do you enjoy working with others to help clean the Chesapeake Bay? Do you have a few hours to spare? Whether growing oysters, planting trees, or helping in our offices, there are plenty of ways you can contribute.
Runoff Pollution Runoff Pollution Urban and suburban polluted runoff is a significant source of harmful nitrogen pollution that continues to grow in the Chesapeake watershed. Stand with CBF as we protect the Bay from polluted runoff. Your submission includes periodic e-mail updates from CBF. However, when water has no way to enter the ground, like when it falls onto a parking lot, it will keep travelling above ground until it hits the nearest river, lake, or sea.
Since this water had no opportunity to deposit whatever it grabbed along the way, it deposits that matter into the water body, where it can begin to have negative effects on the ecosystem. Somewhat diabolically, some of the organisms that most benefit from this are invasive species that are already hurting the ecosystem. As these species feed on the nutrients brought to them by storm water, they continue to outcompete other species, thus aggravating the negative effects they have on food chains.
As phytoplankton and plants bloom and grow from the runoff nutrients , it would be natural to think that they would at least contribute oxygen to the surrounding water, encouraging the existence of other non-photosynthetic species. Somewhat ironically, the opposite is often true. As more of this plant matter grows, more dies and sinks to the bottom of the water body. Bacteria waiting at the bottom then feed on this dead matter while using oxygen and creating more carbon dioxide.
This oxygen-free zone pushes species of fish and other mobile species out, creating an area that is almost unusable in any commercial or recreational way. As the water goes from a beautiful blue swimming hole to a green swampy mess, fewer people will want to use it for swimming or fishing, or even for just looking at.
Quickly, money from tourism and recreation will dry up and leave these areas with a green water body that is doing nothing but hosting extensive plant life. Endangered native species will either begin the painful road toward extinction or move on to a different, more hospitable area. In fact, due in part to the growth of this phenomenon, more than 20 percent of the 10, known freshwater fish species have either gone extinct or become endangered in the past few decades. All of this to say, eutrophication is bad for the health of aquatic ecosystems, as well as the economic health of the communities that are built around them.
The first thing we need to do to address the problem of nutrient-rich stormwater runoff is finding out what exactly is causing it. First and foremost, where are the nutrients coming from? Certainly there is some floating around the environment for water to pick up on its long journey to the sea.
However, the major source of these nutrients, as well as other chemicals like pesticides, are lawns and farms. Water captures the fertilizer that residents put on their lawns and gardens, as well as the pesticides that people apply to the plants that reside in those gardens. Farms also use massive amounts of fertilizer, and animals that are raised on these farms create manure that also contributes to this pollution. Pollution from nutrient-rich stormwater runoff.
Emergency Management. Survey Manual. When rain falls onto the landscape, it doesn't just sit there and wait to be evaporated by the sun or lapped up by the local wildlife—it begins to move due to gravity. Some of it seeps into the ground to refresh groundwater, but most of it flows down gradient as surface runoff.
Runoff is an intricate part of the natural water cycle. After a heavy rainfall you might see sheets of water running downhill When rain falls onto the earth, it just doesn't sit there, it starts moving according to the laws of gravity. A portion of the precipitation seeps into the ground to replenish Earth's groundwater. Most of it flows downhill as runoff. Runoff is extremely important in that not only does it keep rivers and lakes full of water, but it also changes the landscape by the action of erosion.
Flowing water has tremendous power—it can move boulders and carve out canyons; check out the Grand Canyon! Runoff of course occurs during storms, and much more water flows in rivers and as runoff during storms. For example, in during a major storm at Peachtree Creek in Atlanta, Georgia, the amount of water that flowed in the river in one day was 7 percent of all the streamflow for the year.
That part of the precipitation, snow melt, or irrigation water that appears in uncontrolled not regulated by a dam upstream surface streams, rivers, drains or sewers.
Runoff may be classified according to speed of appearance after rainfall or melting snow as direct runoff or base runoff, and according to source as surface runoff, storm interflow, or groundwater runoff.
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