|
Howard Hanson Dam
Howard A. Hanson Dam is an earthen embankment dam on the Green River, 21 miles (34 km) east of Auburn, Washington. The dam was completed in 1961 and its primary purpose is flood control along with water supply for Tacoma, Washington. After the dam's reservoir reached record levels in January 2009, the U.S. Army Corps of Engineers discovered seepage in the right abutment of the dam, leading to efforts to mitigate a potential flood. Improved drainage works were completed in October 2011 and although studies are still underway, the dam was declared safe to maintain its maximum reservoir level. History and construction The Green River Valley was settled in the 1850s and became a notable farming area, until an aphid infestation destroyed the large hop crop in 1890. Since then, the area mainly consisted of dairy and berry farms, but farmers had to cope with yearly floods. These floods would lead to log jams, redirecting the Green and other rivers. Sometimes farmers would clear log ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green River (Duwamish River)
The Green River is a long river in the state of Washington in the United States, arising on the western slopes of the Cascade Range south of Interstate 90. The upper Green River valley forms the western approach to Stampede Pass, and was once home to many small railroad and logging towns such as Weston, Lester, Green River Hot Springs, Nagrom, Maywood, Humphreys, Eagle Gorge, Lemolo, and Kanaskat. Shortly before World War I, the City of Tacoma, Washington, filed for water rights on the Green River. Today, much of the upper valley has become a gated water supply watershed for Tacoma and access is heavily restricted, creating controversy among recreation enthusiasts. Between 1880 and 1888, the Northern Pacific Railway explored and surveyed the Green River. The railway constructed the first direct rail link across Washington's Cascade Range with the opening of their Stampede Tunnel in 1888. History Until 1906, the Green River flowed into the White in downtown Auburn. In 1906, how ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Railroad
Rail transport (also known as train transport) is a means of transport that transfers passengers and goods on wheeled vehicles running on rails, which are incorporated in tracks. In contrast to road transport, where the vehicles run on a prepared flat surface, rail vehicles (rolling stock) are directionally guided by the tracks on which they run. Tracks usually consist of steel rails, installed on sleepers (ties) set in ballast, on which the rolling stock, usually fitted with metal wheels, moves. Other variations are also possible, such as "slab track", in which the rails are fastened to a concrete foundation resting on a prepared subsurface. Rolling stock in a rail transport system generally encounters lower frictional resistance than rubber-tyred road vehicles, so passenger and freight cars (carriages and wagons) can be coupled into longer trains. The operation is carried out by a railway company, providing transport between train stations or freight customer facili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dams In Washington (state)
A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aquaculture, and navigability. Hydropower is often used in conjunction with dams to generate electricity. A dam can also be used to collect or store water which can be evenly distributed between locations. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees (also known as dikes) are used to manage or prevent water flow into specific land regions. The earliest known dam is the Jawa Dam in Jordan, dating to 3,000 BC. The word ''dam'' can be traced back to Middle English, and before that, from Middle Dutch, as seen in the names of many old cities, such as Amsterdam and Rotterdam. History Ancient dams Early dam building took place in Mesopotamia and the Middle East. Dams were use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buildings And Structures In King County, Washington
A building, or edifice, is an enclosed structure with a roof and walls standing more or less permanently in one place, such as a house or factory (although there's also portable buildings). Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a wide number of factors, from building materials available, to weather conditions, land prices, ground conditions, specific uses, prestige, and aesthetic reasons. To better understand the term ''building'' compare the list of nonbuilding structures. Buildings serve several societal needs – primarily as shelter from weather, security, living space, privacy, to store belongings, and to comfortably live and work. A building as a shelter represents a physical division of the human habitat (a place of comfort and safety) and the ''outside'' (a place that at times may be harsh and harmful). Ever since the first cave paintings, buildings have also become objects or canvasses of much artis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tunnel
A tunnel is an underground passageway, dug through surrounding soil, earth or rock, and enclosed except for the entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube construction techniques rather than traditional tunnel boring methods. A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. The central portions of a rapid transit network are usually in the tunnel. Some tunnels are used as sewers or aqueducts to supply water for consumption or for hydroelectric stations. Utility tunnels are used for routing steam, chilled water, electrical power or telecommunication cables, as well as connecting buildings for convenient passage of people and equipment. Secret tunnels are built for military purposes, or by civilians for smuggling of weapons, contraband, or people. Special tunnels, such as wildlife crossings, are built to allow wildlife to cross human-made barriers safely. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and river channel deposits are examples of fluvial transport and deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. Glacial moraine deposits and till are ice-transported sediments. Classification Sediment can be classified based on its grain size, grain shape, and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abutment
An abutment is the substructure at the ends of a bridge span or dam supporting its superstructure. Single-span bridges have abutments at each end which provide vertical and lateral support for the span, as well as acting as retaining walls to resist lateral movement of the earthen fill of the bridge approach. Multi-span bridges require piers to support ends of spans unsupported by abutments. Dam abutments are generally the sides of a valley or gorge, but may be artificial in order to support arch dams such as Kurobe Dam in Japan. The civil engineering term may also refer to the structure supporting one side of an arch, or masonry used to resist the lateral forces of a vault.Pevsner, N. (1970) ''Cornwall''; 2nd ed. Harmondsworth: Penguin; p. 245 The impost or abacus of a column in classical architecture may also serve as an abutment to an arch. The word derives from the verb "abut", meaning to "touch by means of a mutual border". Use in engineering An abutment may be us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Purification
Water purification is the process of removing undesirable chemicals, biological contaminants, suspended solids, and gases from water. The goal is to produce water that is fit for specific purposes. Most water is purified and disinfected for human consumption (drinking water), but water purification may also be carried out for a variety of other purposes, including medical, pharmacological, chemical, and industrial applications. The history of water purification includes a wide variety of methods. The methods used include physical processes such as filtration, sedimentation, and distillation; biological processes such as slow sand filters or biologically active carbon; chemical processes such as flocculation and chlorination; and the use of electromagnetic radiation such as ultraviolet light. Water purification can reduce the concentration of particulate matter including suspended particles, parasites, bacteria, algae, viruses, and fungi as well as reduce the concentration of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tainter Gate
The Tainter gate is a type of radial arm floodgate used in dams and canal locks to control water flow. It is named for Wisconsin structural engineer Jeremiah Burnham Tainter. A side view of a Tainter gate resembles a slice of pie with the curved part of the piece facing the source or upper pool of water and the tip pointing toward the destination or lower pool. The curved face or skinplate of the gate takes the form of a wedge section of cylinder. The straight sides of the pie shape, the trunnion arms, extend back from each end of the cylinder section and meet at a trunnion which serves as a pivot point when the gate rotates. Pressure forces on a submerged body act perpendicular to the body's surface. The design of the Tainter gate results in every pressure force acting through the centre of the imaginary circle of which the gate is a section, so that all resulting pressure force acts through the pivot point of the gate, making construction and design easier. When a Tain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spillway
A spillway is a structure used to provide the controlled release of water downstream from a dam or levee, typically into the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure that water does not damage parts of the structure not designed to convey water. Spillways can include floodgates and fuse plugs to regulate water flow and reservoir level. Such features enable a spillway to regulate downstream flow—by releasing water in a controlled manner before the reservoir is full, operators can prevent an unacceptably large release later. Other uses of the term "spillway" include bypasses of dams and outlets of channels used during high water, and outlet channels carved through natural dams such as moraines. Water normally flows over a spillway only during flood periods, when the reservoir has reached its capacity and water continues entering faster than it can be released. In contrast, an intake tower is a structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
