Water — page 5 of 31

Water terms

401. Bend A change of direction in piping.
402. Beneficial use Water loss through use for the betterment of society, e.g. irrigation or municipal use. See consumptive use.
403. Beneficiary A person who is entitled to receive the benefits or proceeds of a will, trust, insurance policy, retirement plan, annuity, or other contract.
404. Benefit-cost ratio (B/C) The ratio of the present value of project benefits to the present value of the project costs, used in economic analysis.
405. Benthic Occurring at or near the bottom of a body of water.
406. Benthos Organisms living in or on the bottom of a lake, pond, ocean, stream, etc.
407. Bentonitic clay (bentonite) A clay with a high content of the mineral montmorillonite, usually characterized by high swelling on wetting and shrinkage on drying.
408. Berm A horizontal strip or shelf built into an embankment or cut to break the continuity of the slope, usually for the purpose of reducing erosion or to…
409. BEST budget estimate system tools.
410. Best gate The gate opening where the peak efficiency of a turbine occurs at a particular head.
411. BFO Blythe Field Office (Blyth, CA).
412. BIA business impact analysis
413. Biennial A plant which completes its life cycle within two years and then dies.
414. Binder (soil binder) Portion of soil passing a No. 40 (0.425 mm) United States Standard sieve.
415. Binomial Scientific name of plants or animals which has two parts: a genus and a species name.
416. Bioaccumulation See bioconcentration.
417. Bioassay A study of a living organism to measure the effect of a substance, factor, or condition.
418. Bioassimilation The accumulation of a substance within a habitat.
419. Biodiversity The wide diversity and interrelatedness of earth organisms based on genetic and environmental factors.
420. Biological diversity See: biodiversity.
421. Biological growth The activity and growth of any and all living organisms.
422. Biological magnification (biomagnification) Step by step concentration of substances in successive levels of food chains. The enhancement of a substance (usually a contaminant) in a food web such…
423. Biological Opinion (BO) Document stating the U.S. Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) opinion as to whether a Federal action is…
424. Biological processes Processes characteristic of, or resulting from, the activities of living organisms.
425. Biology the science that studies living organisms.
426. Biomass The aggregate amount of living matter or a specific species within a specific habitat, or the total number of a specific species in a specific habitat.
427. Biosphere The part of the earth and its atmosphere that is inhabited by living organisms.
428. Biota The animal and plant life of a region or period.
429. Biotic potential Inherent capacity of an organism to reproduce and survive, which is pitted against limiting influences of the environment.
430. Biotic pyramid Set of all food chains or hierarchic arrangements of organisms as eaters and eaten in a prescribed area when tabulated by numbers or by biomasses, usually…
431. Biotope A small habitat in a large community.
432. Biotype Genetically homogeneous population composed only of closely similar individuals; a genotypic race or group of organisms.
433. BIP Budget Input Program.
434. Bituminous Containing asphalt or tar.
435. Black Ice Transparent ice formed in rivers and lakes, or on roads and bridges.
436. Black water Liquid and solid human body waste and the carriage water generated through toilet usage.
437. Blackout The disconnection of the source of electricity from all the electrical loads in a certain geographical area brought about by an emergency forced outage or…
438. blade Usually a part of an excavator which digs and pushes dirt but does not carry it.
439. BLAST An immature blood cell.
440. Blasting mats A blanket usually composed of woven cable or interlocked rings placed over a blast to reduce flyrock.
441. BLM The Bureau of Land Management.
442. Blockloading Providing a consistent amount of electrical power in a stated period of time.
443. Blue tops Grade stakes whose tops indicate finish grade level.
444. BMP A Windows file format for storing bit map images.
445. BO Biological Opinion.
446. BOD Abbreviation for biological oxygen demand.
447. BOM U.S. Bureau of Mines.
448. BON The necrosis (death) of bone tissue caused by treatment with a bisphosphonate (a drug or substance used to treat osteoporosis, bone pain caused by some…
449. Bonnet The upper portion or the cover of a gate valve body.
450. Bonneville Power Administration (BPA) One of five federal power marketing administrations that sell low cost electric power produced by federal hydro electric dams to agricultural and…
451. Books. See publications.
452. BOR U.S. Bureau of Reclamation.
453. Border Ice An ice sheet in the form of a long border attached to the bank or shore.; shore ice.
454. Borderline soils Soils that have the characteristics of two of the classification groups in the Unified Soil Classification System.
455. Boring Rotary drilling.
456. Borrow Material excavated from one area to be used as fill material in another area.
457. Borrow areas Generally, surface areas, that contain borrow pits. The area from which material for an embankment is excavated.
458. Borrow pits Specific site(s) within a borrow area from which material is excavated for use.
459. Boulder A rock fragment, usually rounded by weathering or abrasion, with an average dimension of 12 inches or more: will not pass a 12-inch screen.
460. Boulder clay A geological term used to designate glacial drift that has not been subjected to the sorting action of water and therefore contains particles from…
461. Box girder A hollow steel beam with a square or rectangular cross section.
462. BPA - Bonneville Power Administration, blanket purchase agreement.
463. Brackish Water of intermediate salinity between seawater and freshwater.
464. Brackish Ice Ice formed from Brackish water.
465. Braided Stream Characterized by successive division and rejoining of streamflow with accompanying islands. A braided stream is composed of anabranches.
466. BRAIN Bureau of Reclamation Acquisition Information Network.
467. Brake horsepower The brake horsepower of a pump is the actual motor input horsepower required to produce the hydraulic horsepower from a pump (flow and head) taking into…
468. Branch An addition to the main pipe in a piping system.
469. Brash Ice Accumulation of floating ice made up of fragments not more than 2 meters across; the wreckage of other forms of ice.
470. BRC - Budget Review Committee, Bureau Procurement Chief.
471. BRD Blackrock Depths
472. Breach 1. The breaking or violating of a law, right or duty, either by an act or omission. 2. The failure to carry out any condition of a contract.
473. Breach hydrograph A flood hydrograph resulting from a dam breach.
474. Breakup The time when a river whose surface has been frozen from bank to bank for a significant portion of its length begins to change to an open water flow…
475. Breakup Date Date on which a body of water is first observed to be entirely clear of ice and remains clear thereafter.
476. Breakup Jam Ice jam that occurs as a result of the accumulation of broken ice pieces.
477. Breakup Period The period of disintegration of an ice cover.
478. Breccia (volcanic breccia) Conglomerate-like rock made up of angular pieces of volcanic rock usually bound in volcanic ash.
479. Brecciated A rock made up of highly angular, coarse fragments.
480. Breeding density Density of sexually mature organisms in a given area during the breeding period.
481. Breeding potential Maximum rate of increase in numbers of individuals of a species or population under optimum conditions.
482. Breeding rate Actual rate of increase of new individuals in a given population; the breeding potential minus limiting factors.
483. Bridge, Class A A bridge located on a Federal-aid highway. Examination of this type of bridge is required every 2 years with an in-depth examination every 6 years.
484. Bridge, Class B A bridge not located on a Federal-aid highway that is used by the public. Examination of this type of bridge is required every 3 years.
485. Bridge, Class C A bridge not located on a Federal-aid highway that can be designated as being a private or operating bridge and could be gated or closed to the public, if…
486. British thermal units (Btu) Quantity of heat required to raise the temperature of one avoirdupois pound of water 1 degree F at or near 39.2 degrees F.
487. BRM business reference model - an organized, hierarchical way to describe the day-to-day business operations of the Federal government; this model presents…
488. Broad-crested weir An overflow structure on which the nappe is supported for an appreciable length in the direction of flow. See weir.
489. Brownout The partial reduction of electrical voltages. A brownout results in lights dimming and motor-driven devices slowing down. See blackout.
490. BSC base safety condition.
491. BSO Business Services Office.
492. BTU - British Thermal Units.
493. Bubbler Gage A water stage recording device that is capable of attaching to a LARC for data automation purposes.
494. bucket A part of an excavator which digs, lifts, and carries dirt.
495. Budget Review Committee (BRC) An ad hoc committee of representatives from each Region, the Reclamation Service Center, and the Washington Office, coordinates Reclamation budget…
496. BUDS business utilization development specialist.
497. Buffer strips (filter strips, vegetated filter strips, grassed buffers) Strips of grass or other close-growing vegetation that separates a waterway (ditch, stream, creek) from an intensive land use area (subdivision, farm).
498. Built Environment The urban environment consisting of buildings, roads, fixtures, parks, and all other improvements that form the physical character of a city.
499. Bulkhead The part of a storefront that forms a base for one or more display windows
500. Bulkhead Gate A gate used either for temporary closure of a channel or conduit before dewatering it for inspection or maintenance or for closure against flowing water…