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A terrace crossing is a geographical zone between the sedimentation (downstream) part and the erosion (upstream) part of the river. This zone develops on the location where the transition of erosion to sedimentation takes place. Upstream of the crossing, terraces will exist. The highest terraces will be the oldest. Downstream of the crossing, older sediments will be buried beneath younger deposits.
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An entrenched river, or entrenched stream is a river or stream that flows in a narrow trench or valley cut into a plain or relatively level upland. Because of lateral erosion streams flowing over gentle slopes over a time develops meandering course. Meanders form where gradient is very gentle, for example in floodplain and delta. Meandering is the feature of the middle and final course of the river. But very deep and wide meanders can also be found cutting hard rocks. Such meanders are called incised or entrenched meanders. The exception is that entrenched meanders are formed during the upliftment of land where river is young. They widen and deepen over time and can be found as deep gorges or canyons in hard rock. In the case of or either an entrenched stream or river, it is often presumed that the watercourse has inherited its course by cutting down into bedrock from a pre-existing plain with little modification of the original course. The down-cutting of the river system could be the result not only of tectonic uplift but also of other factors such as river piracy, decrease of load, increase of runoff, extension of the drainage basin, or change in base level such as a fall in sea level. General, nongeneric terminology for either a river or stream that flows in a narrow trench or valley, for which evidence of a preexisting plain or relatively level upland can be either absent or present is either valley meander or meander valley with the latter term being preferred in literature.
A gully is a landform created by running water, mass movement, or commonly a combination of both eroding sharply into soil or other relatively erodible material, typically on a hillside or in river floodplains or terraces. Gullies resemble large ditches or small valleys, but are metres to tens of metres in depth and width and are characterised by a distinct 'headscarp' or 'headwall' and progress by headward erosion. Gullies are commonly related to intermittent or ephemeral water flow usually associated with localised intense or protracted rainfall events, or snowmelt. Gullies can be formed and accelerated by cultivation practices on hillslopes in farmland, and they can develop rapidly in rangelands from existing natural erosion forms subject to vegetative cover removal and livestock activity.
The Mahakam River is third longest and volume discharge river in Borneo after Kapuas River and Barito River, it is located in Kalimantan, Indonesia. It flows 980 kilometers from the district of Long Apari in the highlands of Borneo, to its mouth at the Makassar Strait.
Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to the forces acting on them: these forces can be due to gravity, centrifugal acceleration, or electromagnetism. Settling is the falling of suspended particles through the liquid, whereas sedimentation is the final result of the settling process.
A culvert is a structure that channels water past an obstacle or to a subterranean waterway. Typically embedded so as to be surrounded by soil, a culvert may be made from a pipe, reinforced concrete or other material. In the United Kingdom, the word can also be used for a longer artificially buried watercourse.
Morgan is a town in South Australia on the right bank of the Murray River, just downstream of where it turns from flowing roughly westwards to roughly southwards. It is about 161 kilometres (100 mi) north east of Adelaide, and about 315 kilometres (196 mi) upstream of the Murray Mouth. At the 2006 census, Morgan had a population of 426.
In geomorphology a river is said to be rejuvenated when it is eroding the landscape in response to a lowering of its base level. The process is often a result of a sudden fall in sea level or the rise of land. The disturbance enables a rise in the river's potential energy, increasing its riverbed erosion rate. The erosion occurs as a result of the river adjusting to its new base level.
In geology, a terrace is a step-like landform. A terrace consists of a flat or gently sloping geomorphic surface, called a tread, that is typically bounded on one side by a steeper ascending slope, which is called a "riser" or "scarp". The tread and the steeper descending slope together constitute the terrace. Terraces can also consist of a tread bounded on all sides by a descending riser or scarp. A narrow terrace is often called a bench.
Gavins Point Dam is a 1.9 mi (3 km) long embankment rolled-earth and chalk-fill dam which spans the Missouri River and impounds Lewis and Clark Lake. The dam joins Cedar County, Nebraska with Yankton County, South Dakota a distance of 811.1 river miles (1,305 km) upstream of St. Louis, Missouri, where the river joins the Mississippi River. The dam and hydroelectric power plant were constructed as the Gavins Point Project from 1952 to 1957 by the United States Army Corps of Engineers as part of the Pick-Sloan Plan. The dam is located approximately 4 miles (6.4 km) west or upstream of Yankton, South Dakota.
The environmental impact of reservoirs comes under ever-increasing scrutiny as the global demand for water and energy increases and the number and size of reservoirs increases.
A volcanic dam is a type of natural dam produced directly or indirectly by volcanism, which holds or temporarily restricts the flow of surface water in existing streams, like a man-made dam. There are two main types of volcanic dams, those created by the flow of molten lava, and those created by the primary or secondary deposition of pyroclastic material and debris. This classification generally excludes other, often larger and longer lived dam-type geologic features, separately termed crater lakes, although these volcanic centers may be associated with the source of material for volcanic dams, and the lowest portion of its confining rim may be considered as such a dam, especially if the lake level within the crater is relatively high.
An antidune is a bedform found in fluvial and other channeled environments. Antidunes occur in supercritical flow, meaning that the Froude number is greater than 1.0 or the flow velocity exceeds the wave velocity; this is also known as upper flow regime. In antidunes, sediment is deposited on the upstream (stoss) side and eroded from the downstream (lee) side, opposite lower flow regime bedforms. As a result, antidunes migrate in an upstream direction, counter to the current flow. Antidunes are called in-phase bedforms, meaning that the water surface elevation mimics the bed elevation; this is due to the supercritical flow regime. Antidune bedforms evolve rapidly, growing in amplitude as they migrate upstream. The resultant wave at the water's surface also increases in amplitude. When that wave becomes unstable, breaks and washes downstream, much of the antidune bedform may be destroyed.
Haslams Creek, a southern tributary of the Parramatta River, is a creek west of Sydney Harbour, located in Sydney, Australia. It flows through Sydney Olympic Park and joins Parramatta River at Homebush Bay. In 1793, the first grants were made to free settlers, with Samuel Haslam receiving his first grant in 1806. A 50 acre grant north of Parramatta Road, the first grant, was followed by a second small grant south of Parramatta Road and east of Haslams Creek. Haslams Creek flowed through the holdings of the Sydney Meat Preserving Company Ltd 1876-1965, which at one point damned the creek. When opened, Lidcombe railway station actually bore the name Haslams Creek Station
A river is a natural flowing watercourse, usually a freshwater stream, flowing on the surface or inside caves towards another waterbody at a lower elevation, such as an ocean, sea, bay, lake, wetland, or another river. In some cases, a river flows into the ground or becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to by names such as creek, brook, and rivulet. There are no official definitions for the generic term river as applied to geographic features, although in some countries or communities, a stream is defined by its size. Many names for small rivers are specific to geographic location; examples are "run" in some parts of the United States, "burn" in Scotland and Northeast England, and "beck" in Northern England. Sometimes a river is defined as being larger than a creek, but not always; the language is vague.
A check dam is a small, sometimes temporary, dam constructed across a swale, drainage ditch, or waterway to counteract erosion by reducing water flow velocity. Check dams themselves are not a type of new technology; rather, they are an ancient technique dating from the second century AD. Check dams are typically, though not always, implemented in a system of several dams situated at regular intervals across the area of interest.
A bar in a river is an elevated region of sediment that has been deposited by the flow. Types of bars include mid-channel bars, point bars, and mouth bars. The locations of bars are determined by the geometry of the river and the flow through it. Bars reflect sediment supply conditions, and can show where sediment supply rate is greater than the transport capacity.
The Ayung River is the longest river on the Indonesian island of Bali. It runs 68.5 km from the northern mountain ranges, passing the Bangli, Badung, Gianyar regencies and the city of Denpasar, before discharging into the Badung Strait at Sanur. The river is famous for white water rafting.
The Lam Phra Phloeng Dam, is a dam on the Lam Phra Phloeng River, part of the Mun River catchment, in the Pak Thong Chai District, Nakhon Ratchasima Province, Thailand. Construction of the dam was completed in 1963, and its reservoir has suffered from very high levels of sedimentation resulting from erosion within its catchment area. Its function is mainly irrigation water supply, although it generates electricity as well.
Djorf Torba Dam is a dam in Kenadsa District, Béchar Province, Algeria, crossing the Oued Guir about 50 kilometres (31 mi) west of the capital, Béchar. It is used for the purposes of irrigation and water supply. The area around the head of the dam features a number of notable ancient monuments. The dam has resulted in a significant reduction in the flow of Oued Guir and Oued Saoura in locations downstream of the dam.
Hicks Creek is a tributary of the Susquehanna River in Luzerne County, Pennsylvania, in the United States. It is approximately 4.5 miles (7.2 km) long and flows through Exeter Township and Exeter. The watershed of the creek has an area of 3.95 square miles (10.2 km2). A reach of the creek is designated as an impaired stream, with the cause of the impairment being sedimentation/siltation and water/flow variability. It is not a perennial stream. The upper reaches of the creek's watershed is mountainous, but the creek has an extremely low gradient in its lower reaches. A reach of the creek has been channelized and a debris basin is located along it. There are several bridge crossings along its course.