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In hydrology, stage is the water level in a river or stream with respect to a chosen reference height. Stage is important because direct measurements of river discharge are very difficult while water surface elevation measurements are comparatively easy. In order to convert stage into discharge, a rating curve is needed. Hydrologists can use a combination of tracer studies, observations of high water marks, numerical modeling, and/or satellite or aerial photography.
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Hydrology is the scientific study of the movement, distribution, and management of water on Earth and other planets, including the water cycle, water resources, and drainage basin sustainability. A practitioner of hydrology is called a hydrologist. Hydrologists are scientists studying earth or environmental science, civil or environmental engineering, and physical geography. Using various analytical methods and scientific techniques, they collect and analyze data to help solve water related problems such as environmental preservation, natural disasters, and water management.
A stream gauge, streamgage or stream gauging station is a location used by hydrologists or environmental scientists to monitor and test terrestrial bodies of water. Hydrometric measurements of water level surface elevation ("stage") and/or volumetric discharge (flow) are generally taken and observations of biota and water quality may also be made. The locations of gauging stations are often found on topographical maps. Some gauging stations are highly automated and may include telemetry capability transmitted to a central data logging facility.
A weir or low-head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the river level. Weirs are also used to control the flow of water for outlets of lakes, ponds, and reservoirs. There are many weir designs, but commonly water flows freely over the top of the weir crest before cascading down to a lower level. There is no single definition as to what constitutes a weir.
The Snowy River is a major river in south-eastern Australia. It originates on the slopes of Mount Kosciuszko, Australia's highest mainland peak, draining the eastern slopes of the Snowy Mountains in New South Wales, before flowing through the Alpine National Park and the Snowy River National Park in Victoria and emptying into Bass Strait.
In hydrology, discharge is the volumetric flow rate of a stream. It equals the product of average flow velocity and the cross-sectional area. It includes any suspended solids, dissolved chemicals, or biologic material in addition to the water itself. Terms may vary between disciplines. For example, a fluvial hydrologist studying natural river systems may define discharge as streamflow, whereas an engineer operating a reservoir system may equate it with outflow, contrasted with inflow.
Schoharie Creek is a river in New York that flows north 93 miles (150 km) from the foot of Indian Head Mountain in the Catskills through the Schoharie Valley to the Mohawk River. It is twice impounded north of Prattsville to create New York City's Schoharie Reservoir and the Blenheim-Gilboa Power Project.
River engineering is a discipline of civil engineering which studies human intervention in the course, characteristics, or flow of a river with the intention of producing some defined benefit. People have intervened in the natural course and behaviour of rivers since before recorded history—to manage the water resources, to protect against flooding, or to make passage along or across rivers easier. Since the Yuan Dynasty and Ancient Roman times, rivers have been used as a source of hydropower. From the late 20th century, the practice of river engineering has responded to environmental concerns broader than immediate human benefit. Some river engineering projects have focused exclusively on the restoration or protection of natural characteristics and habitats.
Streamflow, or channel runoff, is the flow of water in streams and other channels, and is a major element of the water cycle. It is one runoff component, the movement of water from the land to waterbodies, the other component being surface runoff. Water flowing in channels comes from surface runoff from adjacent hillslopes, from groundwater flow out of the ground, and from water discharged from pipes. The discharge of water flowing in a channel is measured using stream gauges or can be estimated by the Manning equation. The record of flow over time is called a hydrograph. Flooding occurs when the volume of water exceeds the capacity of the channel.
A cubic metre per second is the unit of volumetric flow rate in the International System of Units (SI) equal to that of a stere or cube with sides of one metre (39.37 in) in length exchanged or moving each second. It is popularly used for water flow, especially in rivers and streams, and fractions for HVAC values measuring air flow.
Bollard pull is a conventional measure of the pulling power of a watercraft. It is defined as the force exerted by a vessel under full power, on a shore-mounted bollard through a tow-line, commonly measured in a practical test under test conditions that include calm water, no tide, level trim, and sufficient depth and side clearance for a free propeller stream. Like the horsepower or mileage rating of a car, it is a convenient but idealized number that must be adjusted for operating conditions that differ from the test. The bollard pull of a vessel may be reported as two numbers, the static or maximum bollard pull – the highest force measured – and the steady or continuous bollard pull, the average of measurements over an interval of, for example, 10 minutes. An equivalent measurement on land is known as drawbar pull, or tractive force, which is used to measure the total horizontal force generated by a locomotive, a piece of heavy machinery such as a tractor, or a truck,, which is utilized to move a load.
A river mile is a measure of distance in miles along a river from its mouth. River mile numbers begin at zero and increase further upstream. The corresponding metric unit using kilometers is the river kilometer. They are analogous to vehicle roadway mile markers, except that river miles are rarely marked on the physical river; instead they are marked on navigation charts, and topographic maps. Riverfront properties are sometimes partially legally described by their river mile.
A stream is a continuous body of surface water flowing within the bed and banks of a channel. Depending on its location or certain characteristics, a stream may be referred to by a variety of local or regional names. Long, large streams are usually called rivers, while smaller, less voluminous and more intermittent streams are known as streamlets, brooks or creeks.
A river is a natural flowing watercourse, usually a freshwater stream, flowing on the Earth's land 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 these various generic terms for a watercourse as applied to geographic features, although in some countries or communities, a stream is customarily referred to by one of these names as determined 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.
Three components that are included in the load of a river system are the following: dissolved load, wash load and bed material load. The bed material load is the portion of the sediment that is transported by a stream that contains material derived from the bed. Bed material load typically consists of all of the bed load, and the proportion of the suspended load that is represented in the bed sediments. It generally consists of grains coarser than 0.062 mm with the principal source being the channel bed. Its importance lies in that its composition is that of the bed, and the material in transport can therefore be actively interchanged with the bed. For this reason, bed material load exerts a control on river channel morphology. Bed load and wash load together constitute the total load of sediment in a stream. The order in which the three components of load have been considered – dissolved, wash, bed material – can be thought of as progression: of increasingly slower transport velocities, so that the load peak lags further and further behind the flow peak during any event.
In hydrology, a rating curve is a graph of discharge versus stage for a given point on a stream, usually at gauging stations, where the stream discharge is measured across the stream channel with a flow meter. Numerous measurements of stream discharge are made over a range of stream stages. The rating curve is usually plotted as discharge on x-axis versus stage on y-axis.
The Parshall flume is an open channel flow-metering device that was developed to measure the flow of surface water and irrigation flow. A fixed hydraulic structure, the flume is used to measure volumetric flow rate in industrial discharges, municipal sewer lines, and influent/effluent flows in wastewater treatment plants. The Parshall flume accelerates flow through a contraction of both the parallel sidewalls and a drop in the floor at the flume throat. Under free-flow conditions, the depth of water at a specified location upstream of the flume throat can be converted to a rate of flow. Some states specify the use of Parshall flumes, by law, for certain situations.
Roaring Brook is a tributary of the Lackawanna River in Lackawanna County, Pennsylvania, in the United States. It is approximately 21 miles (34 km) long and flows through Covington Township, Madison Township, Moscow, Roaring Brook Township, Elmhurst Township, Dunmore, and Scranton. The watershed of the stream has an area of 56.3 square miles (146 km2). Its named tributaries include Little Roaring Brook, Rock Bottom Creek, White Oak Run, Van Brunt Creek, Bear Brook, and East Branch Roaring Brook. It has a high level of water quality for much of its length. However, it is affected by abandoned mining land, stormwater, and other impacts in its lower reaches. Reservoirs in the watershed include the Hollister Reservoir, the Elmhurst Reservoir, and others. The stream also flows through the Nay Aug Gorge and passes over the Nay Aug Falls, which are on the National Register of Geologic Landmarks. It flows through a concrete channel in its lower reaches. The topography of the watershed contains rolling hills in its upper reaches and the mountainous land of the Moosic Mountains in its lower reaches.
River incision is the narrow erosion caused by a river or stream that is far from its base level. River incision is common after tectonic uplift of the landscape. Incision by multiple rivers result in a dissected landscape, for example a dissected plateau. River incision is the natural process by which a river cuts downward into its bed, deepening the active channel. Though it is a natural process, it can be accelerated rapidly by human factors including land use changes such as timber harvest, mining, agriculture, and road and dam construction. The rate of incision is a function of basal shear-stress. Shear stress is increased by factors such as sediment in the water, which increase its density. Shear stress is proportional to water mass, gravity, and WSS:
Water quality in Taranaki is a notable environmental issue for many stakeholders with concerns about the potential impact from dairy farming in New Zealand and petrochemical industries.
Long Creek is a freshwater stream in southern Maine, United States. It is a tributary of the Fore River, into which it flows at South Portland, at the eastern edge of Portland International Jetport, via Clark Pond, directly south of Thompson's Point on the Portland side of the river. Its main branch is around 3.8 miles (6.1 km) long.