Do you see why this pool cover is not exactly the same as a real drainage basin? There is no outlet for water to exit the "watershed", as almost all watersheds have, such as a stream flowing out of the watershed. Thus, in our pool watershed, you can see how a large "lake" is forming. Rain and snow are key elements in the Earth's water cycle, which is vital to all life on Earth. Rainfall is the main way that the water in the skies comes down to Earth, where it fills our lakes and rivers, recharges the underground aquifers, and provides drinks to plants and animals.
The USGS follows four basic steps for collecting streamflow data. The following example uses a streamgage though more portable methods are also frequently used. Read on to learn more. Water is nature is never really totally clear, especially in surface water, such as rivers and lakes.
Water has color and some extent of dissolved and suspended material, usually dirt particles suspended sediment. Suspended sediment is an important factor in determining the quality of water. The banner picture shows it all — Superhighways! Streets and pavement! House roofs! These are all "impervious surfaces"; impervious to the water from precipitation. When it rains in this locale, water no longer seeps into the ground, but now runs off into storm sewers and then quickly into local creeks.
Localized flooding is too often the result. Skip to main content. Search Search. Water Science School. Watersheds and Drainage Basins. Get SW data. Surface Water Information by Topic Learn more. Science Center Objects Overview Related Science Publications When looking at the location of rivers and the amount of streamflow in rivers, the key concept is the river's "watershed". A tributary at the arctic-boreal transition in the Agashashok River Watershed This picture gives a good representation of a watershed.
Animation of water draining from neighboring basins. Below are other science projects associated with watersheds and drainage basins. Filter Total Items: 4. Year Select Year Apply Filter. A major divide that separates smaller watersheds can be found in the West African country of Ghana. However, there are a number of smaller rivers, such as the Ankobra and Tano Rivers, that are not tributaries of the Volta. They flow independently into the Gulf of Guinea. A minor divide separates rivers that will later converge , or form a confluence.
Most river systems have minor divides. North America's Missouri and Mississippi Rivers form a minor divide. The Missouri River's watershed extends as far north as the Canadian province s of Alberta and Saskatchewan, and as far south as the U. However, the Missouri is a tributary of the Mississippi River. Minor divides are not huge obstacle s to navigation.
Engineer s on ships can usually navigate across a minor divide—the watersheds ultimately flow together. Major divides and continental divides, however, can be very difficult to navigate. Natural features can sometimes help explorers navigate major divides. The Chicago Portage, for instance, is a natural water gap formed through glaciation —the same process that created the Great Lakes. The Chicago Portage links the watersheds of the Great Lakes and the Gulf of Mexico, and is the key reason the city of Chicago became such an important shipping and industrial hub.
Water gaps such as the Chicago Portage are rare, however. In most cases, engineers and geographers must rely on both watercraft and terrestrial transportation to navigate divides. Before the Industrial Revolution , explorers had to portage between major divides. To portage is to carry boats or other vessel s across dry land. For large ships, portaging can be a long, difficult, and expensive journey. Smaller watercraft, such as canoe s, are easier to portage than large ships. For this reason, Native Americans were more skillful at portaging around the rivers of North America than European explorers, who brought large, heavy sailing vessels.
The Industrial Revolution changed the way sailor s navigated. Engineers constructed dam s and canal s between divides. River management techniques controlled the amount of water flowing through parts of a river, and portaging became less necessary. The canals of the St. Lawrence Seaway are an example of industrial technology crossing a major divide. The canals make it possible for ships from the Atlantic Ocean to cross the divide separating the ocean from the watershed of the Great Lakes.
Ships can efficient ly transport both finished good s, such as shoes or cars, and raw material s, such as timber and iron , between the Great Lakes region and the rest of the world. Map courtesy National Geographic Society. Great Divide. Great Lakes. Industrial Revolution. Lawrence Seaway.
Media Credits The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. Water can take many forms, either as a solid, liquid, or gas, but it is more common to see water in its liquid form. We see water in oceans, seas, lakes, streams, ponds, and rivers. Rivers are the foundations of most human settlements; many communities are situated near river systems or river basins.
A river basin is also known as a catchment area, drainage basin, or catchment basin. It can have smaller sub-basins that combine to form a larger water basin. When rain falls or when ice and snow melts, the water that comes from them flows towards a river basin before exiting towards the river, lakes, oceans, or sea. River basins are usually separated by ridges, mountains, and hills.
The water that comes from different sources, such as rivers, ponds, creeks, rainfall, or melting snow and ice flows through them and into the water basin and out into another body of water, usually a larger one.
These landforms are called watersheds which are the divides or elevations that separate the river basin or catchment area. They are also known as drainage divides because they divide the river system or river basins from other river systems.
A watershed is also a term that is being used in the North American region to refer to a water basin which is smaller in size and flows into a smaller outlet such as a stream or wetland. Watersheds are considered part of a water basin. In other regions of the world, watersheds are the drainage divides that cut through a river system.
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