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27-495: Moyola may refer to: River Moyola , Northern Ireland Moyola Park , estate on the river Baron Moyola , title of James Chichester-Clark Maigh Seóla , a plain in County Galway, Ireland Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Moyola . If an internal link led you here, you may wish to change

54-402: A rating curve must be constructed. A rating curve is the functional relation between stage and discharge. It is determined by making repeated discrete measurements of streamflow discharge using a velocimeter and some means to measure the channel geometry to determine the cross-sectional area of the channel. The technicians and hydrologists responsible for determining the rating curve visit

81-561: A current meter or Acoustic Doppler current profiler . One informal methods that is not acceptable for any official or scientific purpose, but can be useful is the float method , in which a floating object such as a piece of wood or orange peel is observed floating down the stream. The first routine measurements of river flow in England began on the Thames and Lea in the 1880s, and in Scotland on

108-429: A branch of Environment and Climate Change Canada . As of 2021, it operates or collects data from more than 2800 gauges across Canada. This data is used by provincial and territory governments to inform flood predictions and water management. In Sri Lanka stream and rivers are monitored by Hydrology and Disaster Management Division a branch of Irrigation Department . It operates nearly 40 gauging station around

135-451: A central data logging facility. Automated direct measurement of stream discharge is difficult at present. Mathematically, measuring stream discharge is estimating the volumetric flow rate , which is in general a flux integral and thus requires many cross-sectional velocity measurements. In place of the direct measurement of stream discharge, one or more surrogate measurements can be used as proxy variables to produce discharge values. In

162-520: A few gauges to provide advisories for navigational purposes. In the Czech Republic, in some measuring places (profiles) are defined three levels which define three degrees of flood-emergency activity. The degree I is a situation of alertness, the degree II is a situation of readiness, the degree III is a situation of danger. Canadian streams and rivers are monitored by the Water Survey of Canada ,

189-566: A mountain stream which flows from near the Glenelly Valley down towards the Moyola where it joins at Sixtowns. Coppies River the smallest tributary an urban stream which flows through the urban areas of Magherafelt it joind the Moyola between Castledawson and Newbridge . The flow or discharge of the river is measured near to its mouth in Lough Neagh. The catchment area to the gauging station

216-448: A stream where the geometry is relatively stable and there is a suitable location to make discrete direct measurements of streamflow using specialized equipment. Many times this will be at a bridge or other stream crossing. Technicians then install equipment that measures the stage (the elevation of the water surface) or, more rarely, the velocity of the flow. Additional equipment is installed to record and transmit these readings (via

243-479: Is 304 square kilometres (117 sq mi), which yields an average flow of 8.4 cubic metres per second (300 cu ft/s). The maximum recorded flow between 1971 and 2012 was 156 cubic metres per second (5,500 cu ft/s) on 19 January 1988. The catchment has a varied geology including limestone, schist, shale and basalt with outcrops of chalk. Overlying this solid geology are superficial deposits of glacial till , plus sand and aggregates . Land use

270-484: Is an extensive network covering all major rivers and catchments in the country. However, a review of existing gauges raised serious concerns about the reliability of the data of a minority of stations, due in part to ongoing funding problems. The largest stream gauge network in Bangladesh is maintained by Bangladesh Water Development Board (BWDB). At few other locations, Bangladesh Inland Water Transport Authority maintains

297-409: Is constructed that relates stage of the stream to cross-sectional area. Using these two ratings, the automatically collected stage produces an estimate of the cross-sectional area, and the automatically collected index velocity produces an estimate of the mean velocity of the cross section . The streamflow discharge is computed as the product of the estimate of the cross section area and the estimate of

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324-612: Is not unlike Wordsworth's Derwent." Gauging station 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

351-522: Is primarily grassland, with areas of bog and heathland, but includes the towns of Magherafelt and Maghera . The average annual rainfall in the catchment is 1,224 millimetres (48.2 in), which is somewhat higher than the average for United Kingdom at 1,101 millimetres (43.3 in). The river is mentioned frequently in the poetry of Seamus Heaney , such as Gifts of Rain and A New Song , Whitby-sur-Moyola and Moyulla . Critic Daniel Tobin suggests that for Heaney his "childhood river, Moyola,

378-804: The Airgiallan kingdoms of Fir Li and Ui Tuirtri. According to Deirdre and Laurence Flanagan in their book, Irish Place Names , the River Moyola derives its name from Magh nÉola , meaning Éolas Plain . The Bridges of the Moyola River are, Upper River: Bealnamala Bridge, Moyard Bridge, Church Bridge, Owenreagh Bridge, Disert Bridge, Derrynoyd Bridge. Middle River: Weddell Bridge, Forgetown Bridge, Lisnamuck Bridge, A29 Fortwilliam Bridge, Curran Bridge A6 Broagh Bridge. Lower River: Dawsons Bridge, Moyola Bridge, Railway Bridge A6 Toome Bypass Bridge, Aughrim Bridge, New Bridge. Douglas River The largest tributary on

405-695: The Geostationary Operational Environmental Satellite ) to the Water Science Center office where the records are kept. The USGS has a Water Science Center office in every state within the United States. Current streamflow data from USGS streamgages may be viewed in map form at: [2] . In Zimbabwe , the national stream gauge network is the responsibility of the Zimbabwe National Water Authority . This

432-552: The River Garry in 1913. The national gauging station network was established in its current form by the early 1970s and consists of approximately 1500 flow measurement stations supplemented by a variable number of temporary monitoring sites. The Environment Agency is responsible for collection and analysis of hydrometric data in England, Natural Resources Wales in Wales, whilst responsibility for Scotland and Northern Ireland rests with

459-596: The Scottish Environment Protection Agency and Rivers Agency respectively. In the United States, the U.S. Geological Survey (USGS) is the principal federal agency tasked with maintaining records of natural resources . Within the USGS, the Water Resources Division carries the responsibility for monitoring water resources. To establish a stream gauge, USGS personnel first choose a site on

486-461: The Sperrin Mountains to Lough Neagh . The Moyola starts a small river (3-5 metres; 10' to 16') for the first few miles of its length and proceeds to expand to a medium-sized river (5-20 metres; 16' to 65') and then to a large river (20 metres +; 65' plus) for its last couple of miles before Lough Neagh. In ancient times, the River Moyola was known as the 'Bior', and served as the border between

513-471: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Moyola&oldid=1041640528 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages River Moyola The River Moyola or Moyola River ( Irish : Abhainn na Scríne ) stretches for approximately 27 miles from

540-488: The lowland area around Curran before joining the river upstream from Curran Bridge. Altagoan River a small river which also starts on Slieve Gallion it flows northwest to join the Moyola. Mullagh River a small river about 3 meters wide along most of its length it starts at the confluence of the Milltown Burn and Back Burn outside Maghera and joins the big river downstream from Ballynahone Bridge. Glengomma Water River

567-434: The majority of cases, a stage (the elevation of the water surface) measurement is used as the surrogate. Low gradient (or shallow-sloped) streams are highly influenced by variable downstream channel conditions. For these streams, a second stream gauge would be installed, and the slope of the water surface would be calculated between the gauges. This value would be used along with the stage measurement to more accurately determine

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594-419: The mean velocity of the streamflow. A variety of hydraulic structures / primary device are used to improve the reliability of using water level as a surrogate for flow (improving the accuracy of the rating table), including: Other equipment commonly used at permanent stream gauge include: Water level gauges: Discharge measurements of a stream or canal without an established stream gauge can be made using

621-661: The river around 20 meters at its widest point it flows from the Feeny Mountain towards Moneyneany and then through the Seven Arch Bridge before joining the Moyola above the Weddell Bridge. Whitewater River The second largest tributary starting up Slieve Gallion flowing a few miles to the village of Straw before joining the river downstream from Disert Bridge. Grange Water River a smallish river around 5 meters wide it starts near Desertmartin before snaking its way across

648-406: The site routinely, with special trips to measure the hydrologic extremes (floods and droughts), and make a discharge measurement by following an explicit set of instructions or standard operating procedures (SOPs). Once the rating curve is established, it can be used in conjunction with stage measurements to determine the volumetric streamflow discharge. This record then serves as an assessment of

675-403: The streamflow discharge. Improvements in the accuracy of velocity sensors have also allowed the use of water velocity as a reliable surrogate for streamflow discharge at sites with a stable cross-sectional area. These sensors are permanently mounted in the stream and measure velocity at a particular location in the stream. In those instances where only a stage measurement is used as the surrogate,

702-424: The technician or hydrologist at a variety of stages. For each discrete determination of streamflow discharge, the mean velocity of the cross section is determined by dividing streamflow discharge by the cross-sectional area. A rating curve, similar to that used for stage-discharge determinations, is constructed using the mean velocity and the index velocity from the permanently mounted meter. An additional rating curve

729-475: The volume of water that passes by the stream gauge and is useful for many tasks associated with hydrology. In those instances where a velocity measurement is additionally used as a surrogate, an index velocity determination is conducted. This analysis uses a velocity sensor, often either magnetic or acoustic, to measure the velocity of the flow at a particular location in the stream cross section. Once again, discrete measurements of streamflow discharge are made by

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