While our planet as a whole may never run out of water, it’s important to remember that clean freshwater is not always available where and when humans need it. In fact, half of the world’s freshwater can be found in only six countries. More than a billion people live without enough safe, clean water.

Humans cannot drink saline water, but, saline water can be made into freshwater, for which there are many uses. The process is called “desalination”, and it is being used more and more around the world to provide people with needed freshwater.

developed by a london-based start-up, QuenchSea is a portable, low cost desalination device that turns saltwater into fresh water. to do so, the apparatus combines a hydraulic system, a triple pre-filtration process, and a small reverse osmosis membrane to desalinate seawater into freshwater using human power only.

20 minutes

It can cost from just under $1 to well over $2 to produce one cubic meter (264 gallons) of desalted water from the ocean. That’s about as much as two people in the U.S. typically go through in a day at home.

Why can’t people drink sea water? Seawater is toxic to humans because your body is unable to get rid of the salt that comes from seawater. Your body’s kidneys normally remove excess salt by producing urine, but the body needs freshwater to dilute the salt in your body for the kidneys to work properly.

Human kidneys can only make urine that is less salty than salt water. Therefore, to get rid of all the excess salt taken in by drinking seawater, you have to urinate more water than you drank. Eventually, you die of dehydration even as you become thirstier.

in the sea, your body does not absorb salt, but it does lose water.

The picture isn’t much better for whales. Even though we haven’t hunted them on an industrial scale for decades, the ocean is still missing 66 to 99 percent of its blubbery behemoths. Blue whales, which urinate so prolifically, are at just 1 percent of their historic numbers in the Southern Hemisphere.

The ice in the Arctic and Antarctica is salt free. You may want to point out the 4 major oceans including the Atlantic, Pacific, Indian, and Arctic. Remember that the limits of the oceans are arbitrary, as there is only one global ocean. Students may ask what are the smaller salty water areas called.

Don Juan Pond

Most lakes have at least one natural outflow in the form of a river or stream, which maintain a lake’s average level by allowing the drainage of excess water. Some lakes do not have a natural outflow and lose water solely by evaporation or underground seepage or both. They are termed endorheic lakes.

A river is a natural flow of running water that follows a well-defined, permanent path, usually within a valley. A stream (also called a brook or a creek) is a natural flow of water that follows a more temporary path that is usually not in a valley.

Small rivers and streams may join together to become larger rivers. Eventually all this water from rivers and streams will run into the ocean or an inland body of water like a lake.

A river forms from water moving from a higher elevation to a lower elevation, all due to gravity. When rain falls on the land, it either seeps into the ground or becomes runoff, which flows downhill into rivers and lakes, on its journey towards the seas. Rivers eventually end up flowing into the oceans.

There are salt water rivers in different places of the world where ground water flows in contact with salt layers. There is a river in Catalonia named Ribera Salada (meaning salty river in Catalan).

A river that does not run dry at any time of year is carrying surplus water from precipitation that collects in the permeable rocks of hills and mountains that surround the watershed. Most rivers get their water from the mountains, where there is far more precipitation than over the lowlands.

In theory, rivers do dry up in the dry season(s). In many cases, major rivers are dammed to prevent too much water from flowing into the sea, to preserve navigability for commercial purposes. Before these dams were built, it was fairly common for major rivers like the Mississippi to dry up, and be less than 3 ft.

If it fell directly over local catchment, then it can come up and go down again in a 24-hour period. If it fell into a lot of upstream catchment as well as local, it might take several days for all that to clear.

Rivers are losing water for a variety of possible reasons, say the researchers, including the installation of dams and the use of water for agriculture. But in many cases the decrease in flow is because of climate change, which is altering rainfall patterns and increasing evaporation because of higher temperatures.

Future of South Aral Sea The South Aral Sea, half of which lies in Uzbekistan, was abandoned to its fate. Most of Uzbekistan’s part of the Aral Sea is completely shriveled up. Only excess water from the North Aral Sea is periodically allowed to flow into the largely dried-up South Aral Sea through a sluice in the dyke.

An arroyo (/əˈrɔɪoʊ/; from Spanish arroyo Spanish: [aˈroʝo], “brook”), also called a wash, is a dry creek, stream bed or gulch that temporarily or seasonally fills and flows after sufficient rain.

A dam is a barrier that stops or diverts the flow of water along a river. Humans have built dams for thousands of years. Dams are built for many purposes.

A river begins at a source (or more often several sources), follows a path called a course and ends at a mouth or mouths. The water in a river is usually confined to a channel, made up of a stream bed between banks. In larger rivers there is often also a wider floodplain shaped by flood-waters over-topping the channel.

1. Toward the middle of a river, water tends to flow fastest; toward the margins of the river it tends to flow slowest. 2. In a meandering river, water will tend to flow fastest along the outside bend of a meander, and slowest on the inside bend.