Water — page 31 of 31

Water terms

3001. Water hammer (hydraulic transient) Refers to pressure fluctuations caused by a sudden increase or decrease in flow velocity, usually associated with a rapid closure or opening of a valve in…
3002. Water holding capacity Amount of soil water available to plants. See available capacity. The smallest value to which the moisture content of a soil can be reduced by gravity…
3003. Water management plan A plan developed during construction to help assure water quality compliance for both point and nonpoint pollution sources.
3004. Water Measurement Manual The Bureau of Reclamation's Water Measurement Manual is available on line at the Water Resources Research Laboratory's website.
3005. Water Pollution The alteration of the constituents of a body of water by man to such a degree that the water loses its value as a natural resource.
3006. Water purveyor An agency or person that supplies water.
3007. Water quality A term used to describe the chemical, physical, and biological characteristics of water, usually with respect to its suitability for a particular purpose.
3008. Water saturation That point at which a material will no longer absorb water.
3009. Water supplier A person who owns or operates a public water system.
3010. Water Supply Outlook A seasonal volume forecast, generally for a period centered around the time of spring snowmelt (e.g., April-July).
3011. Water Supply Outlook (ESS) Product A public product issued by a Forecast Office which contains narrative and numeric information on current and extended water supply conditions.
3012. Water surface elevation (stage) The elevation of a water surface above or below an established reference level, such as sea level. See datum.
3013. Water Table The upper level of ground water; the level below which soil and rock are saturated with water.
3014. Water transfers Selling or exchanging water or water rights among individuals or agencies. Artificial conveyance of water from one area to another.
3015. Water user Any individual, district, association, government agency, or other entity that uses water supplied from a Reclamation project.
3016. Water Year The time period form October 1 through September 30.
3017. Water year (WY) Period of time beginning October 1 of one year and ending September 30 of the following year and designated by the calendar year in which it ends.
3018. Watercourse Any surface flow such as a river, stream, or tributary.
3019. Watershed All land area from which run-off water may enter a pond or lake.
3020. Watershed (drainage area) Surface drainage area above a specified point on a stream. Area which drains into or past a point.
3021. Watershed divide The divide or boundary between catchment areas (or drainage areas).
3022. Waterstage recorder A motor-driven (spring wound or electric) instrument for monitoring water surface elevation.
3023. Waterstop A strip of metal, rubber or other material used to prevent leakage through joints between adjacent sections of concrete.
3024. Waterstop (water bar) A continuous strip of waterproof material placed at concrete joints designed to control cracking and limit moisture penetration.
3025. Watt The rate of energy transfer equivalent to one ampere under an electrical pressure of one volt. One watt equals 1/746 horsepower, or one joule per second.
3026. Watt hour(Wh) An electrical energy unit of measure equal to one watt of power supplied to, or taken from, an electrical circuit steadily for one hour.
3027. Wave runup Vertical height above the sill water level to which water from a specific wave will run up the face of a structure or embankment.
3028. Wave wall. See parapet wall.
3029. Weather Forecast Office (WFO) (WFO) A National Weather Service Weather Forecast Office.
3030. Wedge The wedge can be adjusted during a race to slightly change the handling of the car.
3031. Weep hole A drain embedded in a concrete or masonry structure intended to relieve pressure caused by seepage behind the structure.
3032. Weighing-Type Precipitation Gage A rain gage that weighs the rain or snow which falls into a bucket set on a platform of a spring or lever balance.
3033. Weighting of a slope Additional material placed on the slope of an embankment.
3034. Weir An overflow structure built across an open channel to raise the upstream water level and/or to measure the flow of water.
3035. Weld To build up or fasten together metals by bonding on molten metal.
3036. Well A hole or shaft drilled into the earth to get water or other underground substances.
3037. Well field Area containing one or more wells that produces usable amounts of water.
3038. Well graded A good representation in the material of all particle sizes present from the largest to smallest.
3039. Wellpoint A pipe fitted with a driving point and a fine mesh screen used to remove underground water.
3040. Western Area Power Administration (WAPA) The Western Area Power Administration markets and delivers reliable, cost-based hydroelectric power and related services within a 15-state region of the…
3041. Western Systems Coordinating Council (WSCC) The Western System Coordinating Council is a voluntary industry association created to enhance reliability amoung western utilities.
3042. Wet Floodproofing An approach to floodproofing which usually is a last resort. Flood waters are intentionally allowed into the building to minimize water pressure on the…
3043. Wet unit weight The unit weight of solids plus water per unit volume, irrespective of the degree of saturation.
3044. Wetland Area covered all or part of the year by water. Can be identified by typical plants and soil types.
3045. Wetlands Area having specific hydric soil and water table characteristics supporting or capable of supporting wetlands vegetation.
3046. Wetted perimeter The distance along the bottom and sides of a stream, creek, or channel in contact with the water.
3047. Whaler A horizontal beam in a bracing structure.
3048. Wheeling The process of transmitting electricity over one or more separately owned electric transmission and distribution systems.
3049. White noise Random energy containing all frequency components in equal proportions.
3050. Wholesale customers Any entity that purchases electricity at the wholesale level, including municipal utilities, private utilities, rural electric cooperatives, or…
3051. Wholesale power market The purchase and sale of electricity from generators to resellers (who sell to retail customers) along with the ancillary services needed to maintain…
3052. Wholesale transmission services The transmission of electric energy sold, or to be sold, at wholesale in interstate commerce.
3053. Wholesale Wheeling The wheeling of electric power in amounts and at prices that generally have been negotiated in long term contracts between the power provider and a…
3054. Wicket gate In hydropower applications a gate which pivots open around the periphery of a turbine or pump to allow water to enter.
3055. Wild and Scenic Rivers Act (Public Law 90-542) The Wild and Scenic Rivers Act selects certain rivers possessing remarkable scenic, recreational, geologic, fish and wildlife, historic, or other similar…
3056. Wilderness All lands included in the National Wilderness Preservation System by public law, generally defined as undeveloped federal land retaining its primeval…
3057. Wilderness act See the wilderness act.
3058. Wilderness resource Resources identified in officially designated wilderness areas on Forest Service or Bureau of Land Management administered land.
3059. Wildlife Refuge An area designated for the protection or replenishment of wild animals, within which hunting and fishing are either prohibited or strictly controlled.
3060. Willingness to pay Method of estimating the value of activities, services, or other goods, where value is defined as the maximum amount a consumer would be willing to pay…
3061. Wilting point The moisture content of soil at which plants start to wilt, but not to the extent that they fail to recover when placed in a humid atmosphere.
3062. Winch A drum that can be rotated so as to exert a strong pull while winding in a line.
3063. Wind setup The vertical rise in the still water level at the face of a structure or embankment caused by wind stresses on the surface of the water.
3064. Windrow A ridge of loose material.
3065. Wing wall A wall that guides a water into a conveyance structure.
3066. Winters Doctrine Provides that the establishment of a Indian Reservation impliedly reserves the amount of water necessary for the purposes of the reservation.
3067. Wire Weight Gage A river gage comprised of a weight which is lowered to the water level. The weight is attached to a cable; and as the weight is lowered, a counter…
3068. Wire-to-water efficiency (overall efficiency) The efficiency of a pump and motor together.
3069. Withdrawal A withdrawal is money you take out of your banking, brokerage firm, or other accounts.
3070. Work plan Plans that are prepared which detail the scope, direction, and purpose of a proposed Resource Management Plan.
3071. Wye branch (Y branch) A section of pipe that joins the main run of pipe at an angle. The fitting that makes the joint is in the shape of the letter Y.
3072. Xeriscape Landscaping that does not require a lot of water.
3073. Yield Yield is most commonly associated with a money market fund's return. "Current Yield" is based on daily return, "Effective Yield" on the annual compounded…
3074. Young-of-year Refers to young (usually fish) produced in one reproductive year. Small fish, hatched from eggs spawned in the current year, are considered young-of-year…
3075. Z/R Relationship The empirical conversion relationship between radar reflectivity and precipitation rate.
3076. Zero air voids curve The curve showing the relationship between dry unit weights and corresponding moisture contents, assuming that all of the voids are completely filled with…
3077. Zero Datum A reference "zero" elevation for a stream or river gage. This "zero" can be referenced (usually within ten feet of the bottom of the channel) to mean sea…
3078. Zone of Aeration The comparatively dry soil or rock located between the ground surface and the top of the water table.
3079. Zone of Saturation The soil or rock located below the top of the ground water table that is saturated with water. See water table.
3080. Zoned earthfill (or zoned embankment) An embankment dam composed of zones of selected materials where the permeability of the material increases to the upstream or downstream face from the…
3081. Zoned Embankment Dam An embankment dam, which is composed of zones of selected materials having different degrees of porosity, permeability, and density.
3082. Zoning The ability of local governments to specify the use of private property in order to control development within designated areas of land.
3083. Zooplankton Animals (mostly microscopic) that drift freely in the water column.