Trees and other plant-life also capture the nutrients that the water brings along. 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.
The drizzling or pounding rain picks up and mixes with what's on the ground: Oil, grease, metals and coolants from vehicles; Fertilizers, pesticides and other chemicals from gardens and homes; Bacteria from pet wastes and failing septic systems; Soil from construction sites and other bare ground; Soaps from car or equipment washing; and Accidental spills, leaky storage containers, tobacco spit and whatever else ends up on the ground.
Why is stormwater a problem? Poorly managed stormwater causes three big problems: Pollution from stormwater contaminates our waters, closes local businesses, and harms or kills fish and other wildlife.
As stormwater passes over developed land, it picks up pollutants and transports them to the nearest storm drain and eventually Puget Sound's rivers and bays. Flooding harms streams and wetlands and destroys habitat needed for fish and other wildlife. Unable to soak into the ground, stormwater quickly flows or floods downstream from developed land during the rainy season.
As a result, floods can damage homes and businesses, flood septic system drain fields and overwhelm streams, wetlands and wildlife habitat. Water shortages in growing communities may occur, especially in developed areas with impervious surfaces or areas where water cannot filtrate through, such as roads, parking lots and rooftops.
The impervious surfaces keep rainfall from soaking into the ground and replenishing groundwater and streams used for drinking water or fish habitat. What can you do? You can do a lot to help minimize stormwater problems Start with doing one of the actions on the following top 10 list: Maintain your car or truck. Never dump anything down a storm drain. Always recycle used oil, antifreeze and other fluids. Fix oil leaks in your vehicles. Wash your car at a commercial car wash rather than in the street or in your driveway.
If you wash your car at home, wash it on your lawn. Drive less. In the process of erosion, runoff can carry away the fertile layer of topsoil. Farmers rely on topsoil to grow crops.
Tons of topsoil are lost to runoff every year. People can limit runoff pollution in many ways. Farmers and gardeners can reduce the amount of fertilizer they use.
Urban areas can reduce the number of impervious surfaces. Soil acts as a natural sponge, filter ing and absorbing many harmful chemicals. Communities can plant native vegetation. Shrubs and other plants prevent erosion and runoff from going into waterways. Stormwater Runoff Stormwater runoff is the runoff drained into creeks, bays, and other water sources after a storm. Stormwater runoff includes all debris, chemicals, and other pollutants picked up by the rain or snow. Pesticides can be fungicides which kill harmful fungi , insecticides which kill harmful insects , herbicides which kill harmful plants , or rodenticides which kill harmful rodents.
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Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. Of that, only about 1. Too much manure, fertilizers or sediment may pollute lakes, streams and rivers. Improper use or disposal of pesticides, herbicides or medicines for humans or animals may also cause water quality problems. Excess nutrients from manure or other agricultural runoff raise the amount of nitrogen or phosphorus in the water.
These increases make algae bloom and lower oxygen levels in the water. The increases also make water plants grow too much. Algae blooms, lower oxygen levels and larger plants hurt the life that lives in our water. It also harms water habitats, ruins the natural beauty and can prevent us from using our lakes, streams and rivers for recreation.
Many cities and towns, homes, businesses and farms rely on groundwater for clean drinking water.
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