GEOG-120 Lecture 32: Geog-120 - C32
Document Summary
66% of the largest rivers have been moderately affected by arti cial dams, canals and diversions (rerouting of water) Depleting many sources of surface water and groundwater (1/3 of the world is affected) Nations with arid climates tend to use more fresh water for agriculture (70%) and heavy industrialized nations use a great deal for industry (20%) and residential and municipals uses 10 % Dam is any obstruction placed in a rive or stream to block the ow of water so that water can be stored in a reservoir. Three gorges dam > largest damn; costed a lot of money and damaged 22 cities. To protect against oods, individuals and governments have built dikes and levees along the banks of rivers to hold rising water in main channels. Diversions refers to the process of removing water from its channel or modifying its ow for the purpose of using it elsewhere.