2007-07-07 08:16:18 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Other - Science
Usually rainfall, just by damming a stream or river. But some have it piped in from places like the Hetch Hetchy Reservoir over 100 miles away. Some pump from the California Aqueduct. Some pumped storage reservoirs pump water up into the lake, to be used later to generate hydroelectric power during peak usage periods. Some small ornamental ones just use the city water supply.
2007-07-07 16:24:52 · answer #1 · answered by Frank N 7 · 0⤊ 0⤋
The water from man-made lakes is extracted mostly from gigantic aquifers of sulphuric acid that are located up to two miles underground, mostly in the Western Canadian Provinces. Since the water is indeed a deadly acidic substance, it is necessary before transport to use a neutralizing agent(usually the sap from Amazonian rubber trees-these represent a great bulk of rainforests that are being cut down), to turn the sulphuric acid into stable, drinkable water. NAFTA, which you may have heard of, was a law enacted to allow easier trucking access from Canada to the U.S., so that the water could be brought over in far greater quantities, and was probably the greatest victory that the man-made lake or "reservoir" lobby has ever made in Congress. The downside is that the rainforests are being cut down in massive numbers to fulfill the need for neutralized water that only increases as more reservoirs are put in every day. Additionally, Mexico, Canada's neighbor to the East, is being poisoned by the toxic by-products of the conversion process, which include flouride and aspartame.
Why all the man-made lakes? Well, water weighs a lot, up to 21 lbs. per gallon, depending on its gypsum density, and the weight of man-made lakes that are not used for drinking or irrigation push down on the tectonic plates beneath the earth, along the Mesozoic layer, and cause oil to bubble up from the earth's core. Well, obviously you can see all of the implications of this weighty matter. Get learning and do something about it!
2007-07-07 16:13:43 · answer #2 · answered by Ernesto G 3 · 1⤊ 2⤋
they find a stream or river that runs thru mountains or hills they then damn up one end of it the water backs up...wala instant lake...or reservoir
2007-07-07 15:27:04 · answer #3 · answered by ? 6 · 0⤊ 0⤋
From a big truck with a big hose. A little rain as well.
2007-07-07 15:24:58 · answer #4 · answered by MilVil J 2 · 0⤊ 0⤋
hmm rivers maybe? wondered that myself
2007-07-07 15:23:34 · answer #5 · answered by Spencer M 2 · 0⤊ 0⤋