Water Resources

Updated About encyclopedia.com content Print Article Share Article
views updated

Water Resources

Introduction

Water is the world’s most precious resource because the life of animals and plants depends on it. Most industries also require water for various applications, so the global economy depends on it as well. Most of the water on Earth is saltwater, which cannot be used by terrestrial organisms. Glaciers are the major freshwater resource, while the most important resource for human use is the surface runoff found in lakes and rivers.

Water is a renewable resource through the hydrologic cycle whereby water from the ocean moves onto the land and back again. Sometimes human intervention in the form of dams and pipelines diverts natural water resources to meet local needs. As need for water grows, tensions over water resources are likely to increase. Conservation measures and smarter technologies may help to ensure more equitable distribution of water around the world

Historical Background and Scientific Foundations

The oceans contain about 0.3 billion cubic miles of liquid water, which is around 97% of all water on Earth. Saltwater contains more than one gram per liter of dissolved solids, of which the most significant is sodium chloride or common salt. This renders it unfit for use by terrestrial animals, including humans, and plants, and for most industrial applications. Freshwater contains less than one gram per liter of dissolved solids, and is the main resource for human use. Most of it is, however, inaccessible because it is locked in glaciers, icecaps, and snow cover in the polar regions and elsewhere. Ice and snow account for about 90% of all freshwater. Varying amounts are released into nearby streams at various times during the year where they then become available as resource. Around 1% of all freshwater is available for human use, amounting to only around 0.007% of the total amount of water on Earth.

Fortunately, water is a renewable resource through the hydrologic or water cycle, which allows the vast body of water in the oceans to be tapped for human use. Water molecules at the surface of the oceans evaporate into the atmosphere and move over the land as droplets of freshwater in clouds. These fall as rain or snow, known as precipitation. Some precipitation evaporates and the rest moves either vertically or horizontally on land. The vertical portion fills up pores in rocks, clay, sand, or soil which, when saturated, are known as aquifers. The water in an aquifer is called groundwater. When an aquifer is trapped between two layers of impermeable rocks, the resulting pressure may create an Artesian well that brings the water up to the surface. Pumps can also bring groundwater to the surface through a well. Groundwater is generally of high quality but care should be taken not to draw off too much, as it renews itself only slowly, particularly in dry regions.

Precipitation that moves along horizontally is called surface runoff and it is carried, by gravity, to the nearest body of surface water, which could be a stream, river, pond, or lake. Eventually it arrives back in the ocean, completing the hydrological cycle. Surface water is the most important water resource because it is often readily accessible. A stream is a small channel of water that eventually runs into a river. Streams and rivers account for about nearly 500 billion gallons of water, which is about 0.0001% of the total water on Earth, including the oceans. Yet they are probably the most important water source. If rivers and streams were not replenished by precipitation, melting snow and ice, and seeping groundwater, they would probably run dry in a matter of weeks because of human withdrawals.

A pond is a small body of water that is shallow enough for plants to root there. Lakes are larger bodies

WORDS TO KNOW

AQUIFER: Rock, soil, or sand underground formation that is able to hold and/or transmit water.

GROUNDWATER: Fresh water that is present in an underground location.

SURFACE WATER: Water collecting on the ground or in a stream, river, lake, wetland, or ocean, as opposed to groundwater.

of water whose depths may vary from a few feet to over a mile, as in Lake Baikal in Siberia. Their areas vary from around an acre to hundreds of thousands of acres like Lake Superior, which is really an inland sea. Reservoirs are natural or artificial ponds or lakes used for storing water. Lakes and reservoirs account for around 0.28% of the total water on Earth and they are also an important resource for human use.

Impacts and Issues

Although water is a renewable resource, the amount available for human use is affected by various threats. These include pollution, urban growth, landscape changes, drought, and climate change. Farming, deforestation, mining, and road-building can all impair the quality of water by allowing too much soil and pollutants to enter local rivers, streams, and lakes.

Care must also be taken not too overexploit a water resource. Twenty million people in Chad, Niger, Nigeria, and Cameroon depend on Lake Chad for water. But the lake has shrunk drastically in recent years, and shortages have caused conflicts between the local populations. Meanwhile, the Aral Sea between Kazakhstan and Uzbekistan in Central Asia has been shrinking since the 1960s because two of the rivers that feed it are diverted for irrigation. The water is also heavily polluted because of sewage dumping. Many major rivers, such as the Nile, Ganges, and Rio Grande, are showing signs of drying up. One major factor is that water withdrawals are still being poorly managed and controlled. There has also been a trend to increase groundwater withdrawals, where depletions are less obvious than in surface water. But signs of poor management are there in terms of subsidence, poor water quality, and a sinking water table, which is the top part of an aquifer.

The relationship between climate change and water resources is currently little understood, although it is more likely than not to lead to water shortages. For instance, while climate change tends to shrink glaciers, the effect is not to enrich nearby water resources. Most of the water released tends to evaporate long before it reaches any drought-stricken areas that need it. Global warming increases the incidence of drought, increasing the pressure on water supplies in dry areas. Meanwhile, extreme weather events stemming from global warming, such as floods, tend to degrade the quality of water resources.

Clearly there is a need to develop water resources in a more sustainable manner, taking account of the various pressures on them. Organizations such as the World Health Organization stress that water policy should be driven more by scientific understanding of the consequences of a lack of adequate freshwater for all peoples, rather than by short-term economic or political goals. This includes applying what is known of local water resources and how they interact with the water cycle. Traditionally, rising demand has been met by storing surface water in a reservoir, diverting flows to drier areas, and using increasing amounts of groundwater. Other techniques, such as rainwater collection, desalination, and water reuse can be added to help protect water resources so they can continue to meet local needs without becoming depleted or degraded.

The United Nation’s Millennium Goal number seven—to ensure environmental sustainability—includes the following additional goal: “to reduce by half the proportion of people without sustainable access to safe drinking water.” The UN declared the years 2005–2015 the “Water for Life” decade, an International Decade for Action where all nations should aim to end the unsustainable exploitation of water resources.

Primary Source Connection

The rivers and waterways of the United States have always been used for transportation, irrigation, drinking water, and for the removal of waste. In the twentieth century, many rivers were dammed to prevent flooding and to be harnessed for hydroelectric power. Rivers were diverted or channeled so that their flow could be controlled. Levees were built to contain flooding. Development of the rivers and their adjacent land was seen as a means to increase productivity and economic growth. The Wild and Scenic Rivers Act was signed into the U.S. Code on October 2, 1962 by President Lyndon B. Johnson. The act established the Wild and Scenic Rivers System that oversees the preservation of all rivers that are designated under the act. In order to be designated, a river must be free-flowing and contain an “outstandingly remarkable” feature, such as scenery, historical value, geological features, or particular fish and wildlife. The first three sections and the seventh section of the act are excerpted below.

The Wild and Scenic Rivers Act is considered an important piece of environmental regulation. Since its inception, 156 rivers comprising nearly 11,000 mi (17,700 km) of waterways have been designated part of the Wild and Scenic Rivers System. Although this is an impressive achievement, it contrasts with the more than 600,000 mi (966,000 km) of once free-flowing rivers in the United States that are contained by more than 60,000 dams.

The Wild and Scenic Rivers Act has been criticized for not doing enough to protect rivers from pollution or development (especially along critical feeder streams and banks). However, most environmentalists consider the act to be a valuable conservation tool. No river that has been designated by Congress has ever been removed from the system, indicating that the benefits of the act outweigh any detriments. Part of the reason that the act has been successful is because its intent is not to completely block the use of a designated river, but instead to require that the river be managed so that the fundamental character of the river is preserved. Any development on the river must respect the free flow of water and protect its natural features. The Wild and Scenic Rivers System must co-exist with development so as to create a management plan that protects natural values as well as property values.

WILD AND SCENIC RIVERS ACT

P.L. 90-542, as amended

16 U.S.C. 1271–1287

AN ACT

To provide for a National Wild and Scenic Rivers System, and for other purposes.

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, that

SECTION 1.

(a) this Act may be cited as the “Wild and Scenic Rivers Act.”

(b) It is hereby declared to be the policy of the United States that certain selected rivers of the Nation which, with their immediate environments, possess out standingly remarkable scenic, recreational, geologic, fish and wildlife, historic, cultural, or other similar values, shall be preserved in free-flowing condition, and that they and their immediate environments shall be protected for the benefit and enjoyment of present and future generations. The Congress declares that the established national policy of dam and other construction at appropriate sections of the rivers of the United States needs to be complemented by a policy that would preserve other selected rivers or sections thereof in their free-flowing condition to protect the water quality of such rivers and to fulfill other vital national conservation purposes.

(c) The purpose of this Act is to implement this policy by instituting a national wild and scenic rivers system, by designating the initial components of that system, and by prescribing the methods by which and standards according to which additional components may be added to the system from time to time.

SECTION 2.

(a) The national wild and scenic rivers system shall comprise rivers

  1. that are authorized for inclusion therein by Act of Congress, or
  2. that are designated as wild, scenic or recreational rivers by or pursuant to an act of the legislature of the State or States through which they flow, that are to be permanently administered as wild, scenic or recreational rivers by an agency or political subdivision of the State or States concerned, that are found by the Secretary of the Interior, upon application of the Governor of the State or the Governors of the States concerned, or a person or persons thereunto duly appointed by him or them, to meet the criteria established in this Act and such criteria supplementary thereto as he may prescribe, and that are approved by him for inclusion in the system, including, upon application of the Governor of the State concerned, the Allagash Wilderness Waterway, Maine; that segment of the Wolf River, Wisconsin, which flows through Langlade County; and that segment of the New River in North Carolina extending from its confluence with Dog Creek downstream approximately 26.5 miles to the Virginia State line.

Upon receipt of an application under clause (ii) of this subsection, the Secretary shall notify the Federal Energy Regulatory Commission and publish such application in the Federal Register. Each river designated under clause (ii) shall be administered by the State or political subdivision thereof without expense to the United States other than for administration and management of federally owned lands. For purposes of the preceding sentence, amounts made available to any State or political subdivision under the Land and Water Conservation ‘Fund’ Act of 1965 or any other provision of law shall not be treated as an expense to the United States. Nothing in this subsection shall be construed to provide for the transfer to, or administration by, a State or local authority of any federally owned lands which are within the boundaries of any river included within the system under clause (ii).

(b) A wild, scenic or recreational river area eligible to be included in the system is a free-flowing stream and the related adjacent land area that possesses one or more of the values referred to in Section 1, subsection (b) of this Act. Every wild, scenic or recreational river in its free-flowing condition, or upon restoration to this condition, shall be considered eligible for inclusion in the national wild and scenic rivers system and, if included, shall be classified, designated, and administered as one of the following:

  1. Wild river areas—Those rivers or sections of rivers that are free of impoundments and generally inaccessible except by trail, with watersheds or shore-llines essentially primitive and waters unpolluted. These represent vestiges of primitive America.
  2. Scenic river areas—Those rivers or sections of rivers that are free of impoundments, with shorelines or watersheds still largely primitive and shorelines largely undeveloped, but accessible in places by roads.
  3. Recreational river areas—Those rivers or sections of rivers that are readily accessible by road or railroad, that may have some development along their shorelines, and that may have undergone some impoundment or diversion in the past.

SECTION 7.

(a) The Federal Power Commission shall not license the construction of any dam, water conduit, reservoir, powerhouse, transmission line, or other project works under the Federal Power Act (41 Stat. 1063), as amended (16 U.S.C. 791a et seq.), on or directly affecting any river which is designated in section 3 of this Act as a component of the national wild and scenic rivers system or which is hereafter designated for inclusion in that system, and no department or agency of the United States shall assist by loan, grant, license, or otherwise in the construction of any water resources project that would have a direct and adverse effect on the values for which such river was established, as determined by the Secretary charged with its administration. Nothing contained in the foregoing sentence, however, shall preclude licensing of, or assistance to, developments below or above a wild, scenic or recreational river area or on any stream tributary thereto which will not invade the area or unreasonably diminish the scenic, recreational, and fish and wildlife values present in the area on the date of designation of a river as a component of the national wild and scenic rivers system. No department or agency of the United States shall recommend authorization of any water resources project that would have a direct and adverse effect on the values for which such river was established, as determined by the Secretary charged with its administration, or request appropriations to begin construction of any such project, whether heretofore or hereafter authorized, without advising the Secretary of the Interior or the Secretary of Agriculture, as the case may be, in writing of its intention so to do at least sixty days in advance, and without specifically reporting to the Congress in writing at the time it makes its recommendation or request in what respect construction of such project would be in conflict with the purposes of this Act and would affect the component and the values to be protected by it under this Act. Any license heretofore or hereafter issued by the Federal Power Commission ‘FERC’ affecting the New River of North Carolina shall continue to be effective only for that portion of the river which is not included in the national wild and scenic rivers system pursuant to section 2 of this Act and no project or undertaking so licensed shall be permitted to invade, inundate or otherwise adversely affect such river segment.

(b) The Federal Power Commission ‘FERC’ shall not license the construction of any dam, water conduit, reservoir, powerhouse, transmission line, or other project works under the Federal Power Act, as amended, on or directly affecting any river which is listed in section 5, subsection (a), of this Act, and no department or agency of the United States shall assist by loan, grant, license, or otherwise in the construction of any water resources project that would have a direct and adverse effect on the values for which such river might be designated, as determined by the Secretary responsible for its study or approval

  1. during the ten-year period following enactment of this Act or for a three complete fiscal year period following any Act of Congress designating any river for potential addition to the national wild and scenic rivers system, whichever is later, unless, prior to the expiration of the relevant period, the Secretary of the Interior and where national forest lands are involved, the Secretary of Agriculture, on the basis of study, determine that such river should not be included in the national wild and scenic rivers system and notify the Committees on Interior and Insular Affairs of the United States Congress, in writing, including a copy of the study upon which the determination was made, at least one hundred and eighty days while Congress is in session prior to publishing notice to that effect in the Federal Register: Provided, That if any Act designating any river or rivers for potential addition to the national wild and scenic rivers system provides a period for the study or studies which exceeds such three complete fiscal year period the period provided for in such Act shall be substituted for the three complete fiscal year period in the provisions of this clause (i); and
  2. during such interim period from the date a report is due and the time a report is actually ubmitted to the Congress; and
  3. i) during such additional period thereafter as, in the case of any river the report for which is submitted to the President and the Congress for inclusion in the national wild and scenic rivers system, is necessary for congressional consideration thereof or, in the case of any river recommended to the Secretary of the Interior for inclusion in the national wild and scenic rivers system under section 2(a)(ii) of this Act, is necessary for the Secretary’s consideration thereof, which additional period, however, shall not exceed three years in the first case and one year in the second.

Nothing contained in the foregoing sentence, however, shall preclude licensing of, or assistance to, developments below or above a potential wild, scenic or recreational river area or on any stream tributary thereto which will not invade the area or diminish the scenic, recreational, and fish and wildlife values present in the potential wild, scenic or recreational river area on the date of designation of a river for study as provided in section 5 of this Act. No department or agency of the United States shall, during the periods hereinbefore specified, recommend authorization of any water resources project on any such river or request appropriations to begin construction of any such project, whether heretofore or hereafter authorized, without advising the Secretary of the Interior and, where national forest lands are involved, the Secretary of Agriculture in writing of its intention so to do at least sixty days in advance of doing so and without specifically reporting to the Congress in writing at the time it makes its recommendation or request in what respect construction of such project would be in conflict with the purposes of this Act and would affect the component and the values to be protected by it under this Act.

(c) The Federal Power Commission ‘FERC’ and all other Federal agencies shall, promptly upon enactment of this Act, inform the Secretary of the Interior and, where national forest lands are involved, the Secretary of Agriculture, of any proceedings, studies, or other activities within their jurisdiction which are now in progress and which affect or may affect any of the rivers specified in section 5, subsection (a), of this Act. They shall likewise inform him of any such proceedings, studies, or other activities which are hereafter commenced or resumed before they are commenced or resumed.

(d) Nothing in this section with respect to the making of a loan or grant shall apply to grants made under the Land and Water Conservation Fund Act of 1965 (78 Stat. 897; 16 U.S.C. 4601-5 et seq.).

U.S. Code

U.S. CODE. “WILD AND SCENIC RIVERS ACT.” TITLE 16, CHAPTER 28, SECTIONS 1271, 1272, 1277.

See Also Groundwater; Natural Resource Management; Surface Water; Water Conservation; Water Supply and Demand

BIBLIOGRAPHY

Books

Cunningham, W.P., and A. Cunningham. Environmental Science: A Global Concern. New York: McGraw-Hill International Edition, 2008.

Kaufmann, R., and C. Cleveland. Environmental Science. New York: McGraw-Hill International Edition, 2008.

Web sites

Green Facts: Facts on Health and Environment. “Scientific Facts on Water Resources.” http://www.greenfacts.org/en/water-resources/index.htm#2 (accessed May 2, 2008).

United Nations. “International Decade for Action: Water for Life, 2005-2015.” http://www.un.org/waterforlifedecade/background.html (accessed May 2, 2008).

Susan Aldridge