- Industry: Government
- Number of terms: 15655
- Number of blossaries: 0
- Company Profile:
A U.S. Department of the Interior agency that oversees water resource management incuding the oversight and operation of numerous diversion, delivery, and storage projects the agency has built throughout the western United States for irrigation, water supply, and attendant hydroelectric power ...
Structural measures for the betterment, modernization, or enhancement of an existing facility or system to improve the social, economic, and environmental benefits of the project.
Industry:Engineering
Physical shape of the ground surface. Collective features of the Earth's surface, especially the relief and contour of the land. The arrangement of hills and valleys in a geographic area.
Industry:Engineering
The reservoir water surface elevation below which the reservoir will not be evacuated under normal conditions. The highest applicable water surface elevation described below usually determines the top of inactive capacity.
# The lowest water surface elevation at which the planned minimum rate of release for water supply purposes can be made to canals, conduits, the river, or other downstream conveyance systems. Normally, this elevation is established during the planning and design phases and is the elevation at the end of extreme drawdown periods.
# The established minimum water surface elevation for fish and wildlife purposes.
# The established minimum water surface elevation for recreation purposes.
# The minimum water surface elevation as set forth in compacts and/or agreements with political sudivision(s).
# The minimum water surface elevation at which the powerplant is designed to operate.
# The minimum water surface elevation to which the reservoir can be drawn down using established operating procedures without endangering the dam, appurtenant structures, or reservoir shoreline.
# The minimum water surface elevation or top of inactive capacity established by legislative action.
Industry:Engineering
The ISO is an evolving concept. In general usage, an ISO is a voluntarily-formed entity that ensures comparable and nondiscriminatory access by power suppliers to regional electric transmission systems. As currently envisioned, ISOs would be governed in a manner that renders them "independent" of the commercial interests of power suppliers who also may be owners of transmission facilities in the region. The ISO assumes operational control of the use of transmission facilities, administers a system wide transmission tariff applicable to all market participants, and maintains short-term system reliability. ISOs will develop on a regional basis, reflecting differences among regions in operating and structural characteristics of the transmission grid. Some ISOs also may be responsible for long-range system planning.
Industry:Engineering
Powerplant normally operated to carry baseload; consequently, it operates essentially at a constant load. A plant, usually housing high-efficiency steam-electric units, which is normally operated to take all or part of the minimum load of a system, and which consequently produces electricity at an essentially constant rate and runs continuously. These units are operated to maximize system mechanical and thermal efficiency and minimize system operating costs.
Industry:Engineering
A dedicated, commercially leased, nationwide voice telephone warning system operated on a 24-hour basis, with a National Warning Center and an Alternate National Warning Center staffed by attack warning officers. Special purpose telephone circuits connect the National and Alternate National Warning Centers (NAWAS) to the following: Federal Emergency Management Agency headquarters and regional offices; selected Federal departments and agencies; military installations; and State, county, and city warning points. NAWAS is the only national system designed and maintained to warn the public of a nuclear attack or a natural or manmade disaster.
Industry:Engineering
A gate used to regulate the rate of flow through an outlet works or spillway. A gate or valve that operates under full pressure flow conditions to regulate the rate of discharge.
Industry:Engineering
An overflow structure built across an open channel to raise the upstream water level and/or to measure the flow of water. A measuring or gaging weir is calibrated for depth of flow over the crest. A weir generally consists of a rectangular, trapezoidal, triangular, or other shaped notch, located in a vertical, thin plate over which water flows. The height of water above the weir crest is used to determine the rate of flow. See Cipolletti weir, rectangular weir, and v-notch weir. Other types of weirs include broad-crested weir, sharp-crested weir, drowned weir or submerged weir. See contracted weir and suppressed weir.
Industry:Engineering
Distance between the lowest point in the excavated foundation (excluding narrow fault zones) and the top of dam. The structural height of a concrete dam is the vertical distance between the top of the dam and lowest point of the excavated foundation area, excluding narrow fault zones. The structural height of an embankment dam is the vertical distance between the top of the embankment and the lowest point in the excavated foundation area, including the main cutoff trench, if any, but excluding small trenches or narrow backfilled areas. The top elevation does not include the camber, crown, or roadway surfacing. See hydraulic height.
Industry:Engineering
Paleoflood peak discharges are estimated using geology, fluvial, geomorphology, and stratigraphic records. Geologic information is used to determine flood depths, carbon 14 dating techniques are typically used to determine the time frame when these depths were reached, and hydraulic models, such as step backwater techniques, are used to determine the associated flow given the depth. These floods are used to extend gage records. Floods that have happened approximately 200- to 10,000-years ago can be estimated.
Industry:Engineering
