Appendix A
Glossary
ACEQUIA—
Community-run irrigation ditches and/or the community-run organizations that manage them. This system of water management is rooted in ancient Spanish custom; many still operate in northern New Mexico.
ACRE-FOOT—
The volume of water required to cover 1 acre of land to a depth of 1 foot. Equal to 1.2 megaliters (ML) or 1,233.5 cubic meters (m3).
APPROPRIATION DOCTRINE—
The system of water law dominant in the western United States under which (1) the right to water was acquired by diverting water and applying it to a beneficial use and (2) a right to water acquired earlier in time is superior to a similar right acquired later in time. Also called prior appropriation doctrine. In most states, rights are not now acquired by diverting water and applying it to a beneficial use. Such a system is referred to as the constitutional method of appropriation. Rights are acquired by application, permit, and license, which may not require diversion and application to a beneficial use. Superiority of right is based on earliest in time and has no reference to whether two rights are for a similar use.
AQUIFER—
Water-bearing strata of permeable rock, gravel, or sand.
ARID CLIMATE—
Generally any extremely dry climate.
BASIN—
(1) Hydrology: The area drained by a river and its tributaries. (2) Irrigation: A level plot or field, surrounded by dikes, which may be flood irrigated. (3) Erosion control: A catchment con-
structed to contain and slow runoff to permit the settling and collection of soil materials transported by overland and rill runoff flows.
BENEFICIAL USE—
A use of water resulting in appreciable gain or benefit to the user, consistent with state law, which varies from one state to another.
BENEFIT-COST RATIO—
An economic indicator of the efficiency of a proposed project, computed by dividing benefits by costs; usually, both the benefits and the costs are discounted, so that the ratio reflects efficiency in terms of the present value of future benefits and costs.
CANAL—
A constructed open channel for transporting water from the source of supply to the point of distribution.
CHANNEL—
A natural stream that conveys water; a ditch or channel excavated for the flow of water.
COMMERCIAL WITHDRAWALS—
Water withdrawn for use by motels, hotels, restaurants, office buildings, commercial facilities, and civilian or military institutions. The water may be obtained from a public supply, or it may be self-supplied.
CONJUNCTIVE WATER USE—
The joining together of two sources of water, such as ground water and surface water, to serve a particular use.
CONSUMPTIVE USE—
Use of water that renders it no longer available because it has been evaporated, transpired by plants, incorporated into products or crops, consumed by people or livestock, or otherwise removed from water supplies.
CONVEYANCE LOSS (WATER)—
Loss of water from delivery systems during conveyance, including operational losses and losses due to seepage, evaporation, and transpiration by plants growing in or near the channel.
CORRELATIVE RIGHTS—
Another term for the reasonable use doctrine relating to percolating and riparian waters. In the ground water context, the doctrine of correlative rights will generally limit the appropriation of ground water to the landowner's proportionate share thereof.
DEPLETION—
Net rate of water use from a stream or ground water aquifer for beneficial and nonbeneficial uses. For irrigation or municipal uses, the depletion is the headgate or wellhead diversion minus return flow to the same stream or ground water aquifer.
DISCHARGE (HYDRAULICS)—
Rate of flow, especially fluid flow; the volume of fluid passing a point per unit time, commonly expressed as cubic feet per second, million gallons per day, gallons per minute, or cubic meters per second.
DISSOLVED SOLIDS—
Minerals and organic matter dissolved in water.
DIVERSION—
A turning aside or alteration of the natural course of a flow of water, normally considered physically to leave the natural channel. In some states, this may be a consumptive use direct from a stream, such as by livestock watering. In other states, a diversion must consist of such actions as taking water through a canal, pipe, or conduit.
DOMESTIC WATER USE—
Water used for normal household purposes, such as drinking, food preparation, bathing, washing clothes and dishes, flushing toilets, and watering lawns and gardens. Also called residential water use or domestic withdrawals. The water may be obtained from a public supply or may be self-supplied.
DOMESTIC WITHDRAWALS—
Water used for normal household purposes, such as drinking, food preparation, bathing, washing clothes and dishes, flushing toilets, and watering lawns and gardens. Also called residential water use or domestic water use. The water may be obtained from a public supply or may be self-supplied.
DRAINAGE BASIN—
Land area drained by a river.
DUTY OF WATER—
The total volume of water per year that may be diverted under a vested water right.
EMINENT DOMAIN—
The authority of the federal or state government, or an agency or party authorized by the federal government, to condemn all interest in land for public purposes, after payment of just compensation.
ESTUARY—
That portion of a coastal stream influenced by the tide of the body of water into which it flows, for example, a bay or mouth of a river, where the tide meets the river current; an area where fresh and marine waters mix.
EVAPORATION—
Process by which water is changed from a liquid to a vapor. Also see evapotranspiration.
EVAPOTRANSPIRATION—
The sum of evaporation and transpiration from a unit land area. Also see consumptive use.
FLOOD IRRIGATION—
The application of water in which the entire surface of the soil is covered by a sheet of water, called “controlled flooding” when water is impounded or the flow is directed by border dikes, ridges, or ditches.
FLOODPLAIN—
Land bordering a stream and subject to flooding.
FLOW—
As used in this report, movement of water.
FRESH WATER—
Water that contains less than 1,000 milligrams per liter (mg/L) of dissolved solids; generally more than 500 mg/L is undesirable for drinking and many industrial uses.
GROUND WATER—
Generally, all subsurface water as distinct from
surface water; specifically, the part that is in the saturated zone of a defined aquifer.
GROUND WATER MINING —
The withdrawal of ground water through wells, resulting in a lowering of the ground water table at a rate faster than the rate at which the ground water table can be recharged.
HYDROELECTRIC POWER GENERATION WATER USE—
The instream use of surface water to drive turbines and generate electric power, a nonwithdrawal use.
HYDROLOGIC CYCLE—
The circuit of water movement from the atmosphere to the earth and return to the atmosphere through various stages or processes, such as precipitation, interception, runoff, infiltration, percolation, storage, evaporation, and transpiration.
IMPOUNDMENT—
Generally, an artificial collection or storage of water, as a reservoir, pit, dugout, or sump.
INDUSTRIAL WATER USE—
Water used by manufacturing plants, such as steel, chemical and allied products, paper and allied products, mining, and petroleum refining. The water may be obtained from a public supply or may be self-supplied.
INDUSTRIAL WITHDRAWALS—
Water withdrawn for or used for thermoelectric power (electric utility generation) and other industrial and manufacturing uses such as steel, chemical and allied products, paper and allied products, mining, and petroleum refining. The water may be obtained from a public supply or may be self-supplied.
INSTREAM FLOW REQUIREMENT—
Flow required in a stream to maintain desired instream benefits such as navigation, water quality, fish propagation, and recreation.
INSTREAM FLOW RIGHTS—
A doctrine used to preserve minimum river or streamflows for fish and wildlife, recreation, water quality, and scenic beauty, among other public purposes. Such rights are limited to the use of water within its natural course, not requiring diversion.
INSTREAM USE—
Any use of water that does not require diversion or withdrawal from the natural watercourse, including in-place uses such as navigation and recreation.
INTERBASIN TRANSFER OF WATER—
A transfer of water rights and/ or water from the basin of origin to a different hydrologic basin.
INTERMITTENT STREAM—
A stream or part of a stream that flows only in direct response to precipitation. It receives little or no water from springs and melting snow, or other sources. It is dry for a large part of the year, generally more than 3 months.
INTERSTATE WATERS—
Waters legally defined as rivers, lakes, and other waters that flow across or form a part of state or interna-
tional boundaries; and coastal waters—whose scope has been defined to include ocean water along the coast —that are influenced by tides.
IRRIGATION—
The application of water to soil for crop production or for turf, shrubbery, or wildlife food and habitat. Provides water requirements of plants not satisfied by rainfall.
IRRIGATION DISTRICT—
In the United States, a cooperative, self-governing public corporation set up as a subdivision of the state, with definite geographic boundaries, organized to obtain and distribute water for irrigation of lands within the district; created under authority of the state legislature with the consent of a designated fraction of the landowners or citizens and having taxing power.
IRRIGATION EFFICIENCY—
Ratio of irrigation water used in evapotranspiration to the water applied or delivered to a field or farm. This is one of several indices used to compare irrigation systems and to evaluate practices.
IRRIGATION FREQUENCY—
Time interval between irrigations.
IRRIGATION RETURN FLOW—
The part of applied water that is not consumed by evapotranspiration and that migrates to an aquifer or surface water body. See also return flow.
IRRIGATION WATER REQUIREMENT—
The quantity, or depth, of water in addition to precipitation, required to obtain desired crop yield and to maintain a salt balance in the crop root zone.
IRRIGATION WITHDRAWALS—
Withdrawal of water for application on land to assist in the growing of crops and pastures or to maintain recreational lands.
JUNIOR RIGHTS—
A junior water rights holder is one who holds rights that are temporarily more recent than senior rights holders. All water rights are defined in relation to other users, and a water rights holder only acquires the right to use a specific quantity of water under specified conditions. Thus, when limited water is available, junior rights are not met until all senior rights have been satisfied.
MEGALITER—
A measure of volume: 1 ML equals 0.8107 acre-foot; 1 acre-foot equals 1.23 ML and is the volume of water required to cover 1 acre of land to a depth of 1 foot.
NET DEPLETION—
Total water consumed by irrigation, or other use in an area, equal to water withdrawn minus return flow.
OFF-SITE USE—
A use of water away from the point of diversion or withdrawal.
OFF-STREAM USE—
Water withdrawn or diverted from a ground or surface water source of use.
OUTLET—
Point of water disposal from a stream, river, lake, tidewater, or artificial drain.
PER CAPITA USE—
The average amount of water used per person per day.
PERFECTED WATER RIGHT—
A water right to which the owner has applied for and obtained a permit, has complied with the conditions of the permit, and has obtained a license or certificate of appropriation.
PERMIT SYSTEM—
A general term referring to a system of acquiring water rights under state law whereby the state must issue a permit for a new use of water; although permit systems were, at one time, generally associated with eastern states using the riparian doctrine, they are now found elsewhere as well.
PLACE-OF-USE LIMITATION—
In the water law context, the act of defining a water right so that the owner of the right may not freely change the place of use without consideration of the effect of such change on other water users.
POINT SOURCE OF POLLUTION—
Pollution originating from any discrete source, such as the outflow from a pipe, ditch, tunnel, well, concentrated animal-feeding operation, or floating craft.
PRECIPITATION—
Includes rain, snow, hail, and sleet.
PRIOR APPROPRIATION—
A concept in water law under which a right is determined by such a procedure as having the earliest priority date.
PRIORITY OF USE AND STATUTORY PREFERENCES—
Under appropriation water law systems, priority of use refers to the date a water right is acquired, with senior rights prevailing over junior rights. Priority of use must be distinguished from statutory preferences, which refer to statutory statements of preference among types of beneficial use and would come into play, for example, in deciding which of two concurrent water rights should be satisfied first during a shortage of water or which of two competing applications for a water right should be granted.
PUBLIC INTEREST—
An interest or benefit accruing to society generally, rather than to any individuals or groups of individuals in the society.
PUBLIC SUPPLY—
Water withdrawn for all uses by public and private water suppliers and delivered to users that do not supply their own water. Water suppliers provide water for a variety of uses such as domestic, commercial, industrial, and public water use.
PUBLIC TRUST DOCTRINE—
A poorly defined judicial doctrine under which the state holds its navigable waters and underlying beds in trust for the public and is required or authorized to protect the public interest in such waters. All water rights issued by the
state are subject to the overriding interest of the public and the exercise of the public trust by state administrative agencies.
PUBLIC WATER USE—
Water from a public supply used for fire fighting, street washing, and municipal parks and swimming pools. See also public supply.
RAINFALL—
Quantity of water that falls as rain only. Not synonymous with precipitation.
REACH—
A specified length of a stream or channel.
REASONABLE USE—
A rule with regard to percolating or riparian water restricting the landowner to a reasonable use of his own rights and property in view of and qualified by the similar rights of others, and the condition that such use not injure others in the enjoyment of their rights.
RECHARGE—
Process by which water is added to the zone of saturation, as recharge of an aquifer.
RECHARGE AREA (GROUND WATER)—
An area in which water infiltrates the ground and reaches the zone of saturation.
RECLAIMED SEWAGE—
Treatment plant effluent that has been diverted or intercepted for use before it reaches a natural waterway or aquifer.
RECYCLED WATER—
Water that is used more than one time by the same user.
REGULATION OF A STREAM—
Artificial manipulation of the flow of a stream.
RENEWABLE WATER SUPPLY—
The rate of supply of water (volume per unit time) potentially or theoretically available for use in a region on an essentially permanent basis.
RESERVED WATER RIGHTS—
This class of water rights is a judicial creation derived from Winters v. United States (207 U.S. 564, 1907) and subsequent federal case law, which collectively hold that when the federal government withdraws land from general use and reserves it for a specific purpose, the federal government by implication reserves the minimum amount of water unappropriated at the time the land was withdrawn or reserved to accomplish the primary purpose of the reservation. Federal reserved water rights may be claimed when Congress has by statute withdrawn lands from the public domain for a particular federal purpose or where the President has withdrawn lands from the public domain for a particular federal purpose pursuant to congressional authorization.
RETURN FLOW—
The amount of water that reaches a ground or surface water source after release from the point of use and thus becomes available for further use. See also irrigation return flow.
REUSE—
Repeated use of the same water by subsequent users in sequential systems.
RIPARIAN DOCTRINE—
The system of law dominant in Great Britain and the eastern United States, in which owners of lands along the banks of a stream or water body have the right to reasonable use of the waters and a correlative right protecting against unreasonable use by others that substantially diminishes the quantity or quality of water. The right is appurtenant to the land and does not depend on prior use.
RIPARIAN LAND—
Land situated along the bank of a stream or other body of water.
RIPARIAN RIGHTS—
A concept of water law under which authorization to use water in a stream is based on ownership of the land adjacent to the stream and normally not lost if not used.
RUNOFF—
That part of the precipitation that moves from the land to surface water bodies.
SAFE YIELD (GROUND WATER)—
Amount of water that can be withdrawn from an aquifer without producing an undesired effect.
SAFE YIELD (SURFACE WATER)—
Amount of water that can be withdrawn or released from a reservoir on an ongoing basis with an acceptably small risk of supply interruption (reducing the reservoir storage to zero).
SALINITY—
Concentration of dissolved salts in water or soil water.
SALVAGE—
Saving or conserving water by improving the efficiency of use (e.g., by lining irrigation canals so seepage losses are reduced).
SENIOR RIGHTS—
A senior water rights holder is one who holds rights that are older than those of junior rights holders. All water rights are defined in relation to other users, and a water rights holder only acquires the right to use a specific quantity of water under specified conditions. Thus, when limited water is available, senior rights are satisfied first.
STREAM DEPLETION—
See depletion.
SURFACE WATER—
An open body of water such as a stream, lake, or reservoir.
THIRD PARTIES—
The people, communities, and environments not directly engaged in a transfer of water or water rights (i.e., the buyers or sellers) but still affected by the transfer. These affected parties can include areas of origin, Indian tribes, other minority cultures (primarily Hispanic), communities that depend on irrigated agriculture or water-based recreation, boaters, anglers, and broad segments of the public who care about wetlands, riparian areas, endangered species, instream flows, and other environmental values that might be harmed or enhanced by a change in water use.
TRANSFER—
A movement of water or water rights that involves a change in point of diversion, a change in type of use, or a change in location of use.
TRANSFER (CONVEYANCE OF WATER RIGHT)—
A passing or conveyance of title to a water right; a permanent assignment as opposed to a temporary lease or disposal of water.
WASTEWATER—
Water that carries wastes from homes, businesses, and industries; a mixture of water and dissolved or suspended solids.
WATER CONSUMED—
See consumptive use.
WATER DEMAND—
Water requirements for a particular purpose, such as irrigation, power, municipal supply, plant transpiration, or storage.
WATER MANAGEMENT—
Application of practices to obtain added benefits from precipitation, water, or water flow in any of a number of areas, such as irrigation, drainage, wildlife and recreation, water supply, watershed management, and water storage in soil for crop production. Includes irrigation water management and watershed management.
WATER QUALITY—
The chemical, physical, and biological condition of water related to beneficial use.
WATER RESOURCE—
The supply of ground and surface water in a given area.
WATER RESOURCE REGION—
Natural drainage basin or hydrologic area that contains either the drainage area of a major river or the combined areas of a series of rivers.
WATER RESOURCE SUBREGION—
A subregion of a water resource region that includes the area drained by a river system, a reach of a river and its tributaries in that reach, a closed basin(s), or a group of streams forming a coastal drainage area.
WATER RIGHT—
The legal right to use a specific quantity of water, on a specific time schedule, at a specific place, and for a specific purpose.
WATER RIGHTS, CORRELATIVE DOCTRINE—
When a source of water does not provide enough for all users, the water is reapportioned proportionately on the basis of prior water rights held by each user.
WATER USE EFFICIENCY—
Marketable crop production per unit of water consumed in evapotranspiration.
WATER WITHDRAWAL—
Water removed from ground or surface water for use.
