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50-498: Hutt can refer to: Places [ edit ] New Zealand [ edit ] Hutt River (New Zealand) , name after William Hutt (politician) . Hutt Valley , an area inland from Wellington Hutt County , a former county in the Hutt Valley Lower Hutt ('Hutt City'), a territorial authority (formerly part of Hutt County) Upper Hutt ('Upper Hutt City'),

100-439: A collaboration between Wellington Regional Council , local Rotary International clubs, Hutt City Council , Upper Hutt City Council and other groups. The Hutt River Trail, a 29 kilometre cycling and walking route, follows the entire length of the river from Petone to Kaitoke Regional Park at Upper Hutt , linking up to Kaitoke Regional Park . Most of the track is gravel, but some is sealed or grass. Some low-lying parts of

150-571: A fictional alien species Hutt International Boys' School , a state integrated boys' secondary school in Upper Hutt, New Zealand Hutt Intermediate School , Lower Hutt, New Zealand Hutt Recreation Ground , a football, cricket and rugby union ground in Lower Hutt, New Zealand See also [ edit ] Principality of Hutt River , a self-proclaimed independent state within the borders of Western Australia Topics referred to by

200-554: A flood-prone property to qualify for government-subsidized insurance, a local community must adopt an ordinance that protects the floodway and requires that new residential structures built in Special Flood Hazard Areas be elevated to at least the level of the 100-year flood. Commercial structures can be elevated or floodproofed to or above this level. In some areas without detailed study information, structures may be required to be elevated to at least two feet above

250-445: A floodplain. The quantity of sediments in a floodplain greatly exceeds the river load of sediments. Thus, floodplains are an important storage site for sediments during their transport from where they are generated to their ultimate depositional environment. When the rate at which the river is cutting downwards becomes great enough that overbank flows become infrequent, the river is said to have abandoned its floodplain. Portions of

300-622: A name adopted by an Upper Hutt suburb and secondary school . The river was named Hutt after Sir William Hutt , chairman of the New Zealand Company . This name was given by Captain Edward Main Chaffers and Colonel William Wakefield while charting Port Nicholson in 1839. The official name since 2011 is Te Awa Kairangi / Hutt River. For most of its length, the Hutt is a shallow and sometimes braided river in

350-460: A number of fertile floodplains , including Kaitoke , central Upper Hutt and Lower Hutt . The Hutt River Trail, a regional park administered by Wellington Regional Council , runs alongside the eastern side of the river. Early Māori residents, such as Ngāi Tara, called the river Te Awa Kairangi. Later Māori settlers named it Te Wai o Orutu after Orutu, a Ngāti Mamoe ancestor. By the time European settlers arrived, Māori called it Heretaunga,

400-591: A territorial authority (formerly part of Hutt County) Hutt (New Zealand electorate) , a former electorate, 1983-1956 Mount Hutt , a mountain and ski field in the Southern Aps Australia [ edit ] Hutt River (South Australia) Hutt River (Western Australia) Hutt Lagoon , Western Australia Hutt Street , Adelaide, South Australia Antarctica [ edit ] Hutt Peak , Marie Byrd Land Other uses [ edit ] Hutt (surname) Hutt ( Star Wars ) ,

450-599: A wide rocky bed, but in the Kaitoke gorge the river flows directly over bedrock , and approaching the mouth at Petone the river is narrower and the banks steeper. The larger populated areas in Upper Hutt and Lower Hutt are protected from flooding by stopbanks and introduced willow trees , as is common in New Zealand. The headwaters in the Kaitoke Regional Park are closed to preserve the quality of

500-546: Is a problem in freshwater systems. Much of the phosphorus in freshwater systems comes from municipal wastewater treatment plants and agricultural runoff. Stream connectivity controls whether phosphorus cycling is mediated by floodplain sediments or by external processes. Under conditions of stream connectivity, phosphorus is better able to be cycled, and sediments and nutrients are more readily retained. Water in freshwater streams ends up in either short-term storage in plants or algae or long-term in sediments. Wet/dry cycling within

550-406: Is advantageous for the rapid colonization of large areas of the floodplain. This allows them to take advantage of shifting floodplain geometry. For example, floodplain trees are fast-growing and tolerant of root disturbance. Opportunists (such as birds) are attracted to the rich food supply provided by the flood pulse. Floodplain ecosystems have distinct biozones. In Europe, as one moves away from

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600-498: Is any area subject to inundation by a 100-year flood. A problem is that any alteration of the watershed upstream of the point in question can potentially affect the ability of the watershed to handle water, and thus potentially affects the levels of the periodic floods. A large shopping center and parking lot, for example, may raise the levels of 5-year, 100-year, and other floods, but the maps are rarely adjusted and are frequently rendered obsolete by subsequent development. In order for

650-460: Is described as vertical accretion , since the deposits build upwards. In undisturbed river systems, overbank flow is frequent, typically occurring every one to two years, regardless of climate or topography. Sedimentation rates for a three-day flood of the Meuse and Rhine Rivers in 1993 found average sedimentation rates in the floodplain of between 0.57 and 1.0 kg/m . Higher rates were found on

700-420: Is different from Wikidata All article disambiguation pages All disambiguation pages Hutt River (New Zealand) The Hutt River ( Māori : Te Awa Kairangi , Te Wai o Orutu or Heretaunga ; officially Te Awa Kairangi / Hutt River ) flows through the southern North Island of New Zealand . It flows south-west from the southern Tararua Range for 56 kilometres (35 mi), forming

750-565: Is largely a result of flood control, hydroelectric development (such as reservoirs), and conversion of floodplains to agriculture use. Transportation and waste disposal also have detrimental effects. The result is the fragmentation of these ecosystems, resulting in loss of populations and diversity and endangering the remaining fragments of the ecosystem. Flood control creates a sharper boundary between water and land than in undisturbed floodplains, reducing physical diversity. Floodplain forests protect waterways from erosion and pollution and reduce

800-402: Is most common in sections of rivers where the river bed is accumulating sediments ( aggrading ). Repeated flooding eventually builds up an alluvial ridge, whose natural levees and abandoned meander loops may stand well above most of the floodplain. The alluvial ridge is topped by a channel belt formed by successive generations of channel migration and meander cutoff. At much longer intervals,

850-541: The Wellington Fault to Maoribank . The movement of the fault can be seen from the displacement of the river terraces in Harcourt Park. At the top of the Upper Hutt floodplain, the river makes a sharp turn against the bedrock at the foot of the cliff at Maoribank to flow down the valley. The Upper Hutt floodplain contains the greater portion of Upper Hutt city. The Whakatiki River joins the Hutt from

900-557: The Yellow River in China – see list of deadliest floods . The worst of these, and the worst natural disaster (excluding famine and epidemics), was the 1931 China floods , estimated to have killed millions. This had been preceded by the 1887 Yellow River flood , which killed around one million people and is the second-worst natural disaster in history. The extent of floodplain inundation depends partly on flood magnitude, defined by

950-610: The drinking water drawn off at Kaitoke to supply the greater Wellington area. Below Kaitoke is the Kaitoke Gorge, a popular destination for rafting . Below the gorge is Te Mārua , where the Mangaroa River joins the Hutt from the east. Further down, at Birchville , the Akatarawa River joins the Hutt from the west. Here it flows in a deep channel between the surrounding hills and is turned to flow across

1000-747: The return period . In the United States, the Federal Emergency Management Agency (FEMA) manages the National Flood Insurance Program (NFIP). The NFIP offers insurance to properties located within a flood-prone area, as defined by the Flood Insurance Rate Map (FIRM), which depicts various flood risks for a community. The FIRM typically focuses on the delineation of the 100-year flood inundation area, also known within

1050-560: The NFIP as the Special Flood Hazard Area. Where a detailed study of a waterway has been done, the 100-year floodplain will also include the floodway, the critical portion of the floodplain which includes the stream channel and any adjacent areas that must be kept free of encroachments that might block flood flows or restrict storage of flood waters. Another commonly encountered term is the Special Flood Hazard Area, which

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1100-400: The abandoned floodplain may be preserved as fluvial terraces . Floodplains support diverse and productive ecosystems . They are characterized by considerable variability in space and time, which in turn produces some of the most species-rich of ecosystems. From the ecological perspective, the most distinctive aspect of floodplains is the flood pulse associated with annual floods, and so

1150-511: The advantages provided by the richness of the alluvial soil of the floodplain are severely offset by frequent floods brought on by cyclones and annual monsoon rains. These extreme weather events cause severe economic disruption and loss of human life in the densely-populated region. Floodplain soil composition is unique and varies widely based on microtopography. Floodplain forests have high topographic heterogeneity which creates variation in localized hydrologic conditions. Soil moisture within

1200-653: The aquifer from a five-kilometre stretch of the Hutt River south of Taita Gorge, at the rate of 1000 litres per second. It takes several years for water in the underground aquifer to reach Waterloo from the Taita Gorge, and about 10 years to reach the Petone foreshore. The water level in Wellington Harbour was much lower 20,000 years ago, and the ancient Hutt River used to flow down a paleochannel to

1250-409: The bush, the river banks began to disintegrate and collapse into the river. This led to soil being washed into the river, more flooding and changes in the river's course. Writing in 1880, James Coutts Crawford described the river as he had seen it in 1840: The alluvial land on the banks of the Hutt was at this time covered by a dense forest, many of the trees being of gigantic size. Boats could ascend

1300-467: The channel shifts varies greatly, with reported rates ranging from too slow to measure to as much as 2,400 feet (730 m) per year for the Kosi River of India. Overbank flow takes place when the river is flooded with more water than can be accommodated by the river channel. Flow over the banks of the river deposits a thin veneer of sediments that is coarsest and thickest close to the channel. This

1350-548: The east of Matiu / Somes Island as far as the present-day Miramar Peninsula . Much of the water in the Waiwhetu Aquifer moves under the sea bed from the direction of the Hutt River to the Falcon Shoals area (between Karaka Bay and Worser Bay ) at the harbour mouth via the paleochannel. State Highway 2 follows the course of the river for most of its length, with the exception of the Kaitoke Gorge and

1400-472: The flood waters. This can encourage farming ; some important agricultural regions, such as the Nile and Mississippi river basins , heavily exploit floodplains. Agricultural and urban regions have developed near or on floodplains to take advantage of the rich soil and freshwater. However, the risk of inundation has led to increasing efforts to control flooding . Most floodplains are formed by deposition on

1450-448: The floodplain ecosystem is defined as the part of the river valley that is regularly flooded and dried. Floods bring in detrital material rich in nutrients and release nutrients from dry soil as it is flooded. The decomposition of terrestrial plants submerged by the floodwaters adds to the nutrient supply. The flooded littoral zone of the river (the zone closest to the river bank) provides an ideal environment for many aquatic species, so

1500-462: The floodplain has a big impact on phosphorus availability because it alters water level, redox state, pH, and physical properties of minerals. Dry soils that were previously inundated have reduced availability of phosphorus and increased affinity for obtaining phosphorus. Human floodplain alterations also impact the phosphorus cycle. Particulate phosphorus and soluble reactive phosphorus (SRP) can contribute to algal blooms and toxicity in waterways when

1550-599: The floodplain. Other smaller-scale mitigation efforts include acquiring and demolishing flood-prone buildings or flood-proofing them. In some floodplains, such as the Inner Niger Delta of Mali , annual flooding events are a natural part of the local ecology and rural economy , allowing for the raising of crops through recessional agriculture . However, in Bangladesh , which occupies the Ganges Delta ,

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1600-587: The head waters, before crossing the Remutaka Range into the Wairarapa . In the early nineteenth century, the Hutt River was deeper than it is now and navigable for some distance by large canoes and boats. Māori would take produce grown in the Hutt Valley down the river by canoe and across the harbour to Wellington city. Thick bush grew down to the water's edge. When early European settlers cleared

1650-465: The impact of floodwaters. The disturbance by humans of temperate floodplain ecosystems frustrates attempts to understand their natural behavior. Tropical rivers are less impacted by humans and provide models for temperate floodplain ecosystems, which are thought to share many of their ecological attributes. Excluding famines and epidemics , some of the worst natural disasters in history (measured by fatalities) have been river floods, particularly in

1700-448: The inside of river meanders and by overbank flow. Wherever the river meanders, the flowing water erodes the river bank on the outside of the meander. At the same time, sediments are simultaneously deposited in a bar on the inside of the meander. This is described as lateral accretion since the deposition builds the point bar laterally into the river channel. Erosion on the outside of the meander usually closely balances deposition on

1750-417: The inside so that the channel shifts in the direction of the meander without changing significantly in width. The point bar is built up to a level very close to that of the river banks. Significant net erosion of sediments occurs only when the meander cuts into higher ground. The overall effect is that, as the river meanders, it creates a level flood plain composed mostly of point bar deposits. The rate at which

1800-457: The levees (4 kg/m or more) and on low-lying areas (1.6 kg/m ). Sedimentation from the overbank flow is concentrated on natural levees, crevasse splays , and in wetlands and shallow lakes of flood basins. Natural levees are ridges along river banks that form from rapid deposition from the overbank flow. Most of the suspended sand is deposited on the levees, leaving the silt and clay sediments to be deposited as floodplain mud further from

1850-617: The makeup towards ash (49%) with maple increasing to 14% and oak decreasing to 25%. Semiarid floodplains have a much lower species diversity. Species are adapted to alternating drought and flood. Extreme drying can destroy the ability of the floodplain ecosystem to shift to a healthy wet phase when flooded. Floodplain forests constituted 1% of the landscape of Europe in the 1800s. Much of this has been cleared by human activity, though floodplain forests have been impacted less than other kinds of forests. This makes them important refugia for biodiversity. Human destruction of floodplain ecosystems

1900-762: The nitrogen-to-phosphorus ratios are altered farther upstream. In areas where the phosphorus load is primarily particulate phosphorus, like the Mississippi River, the most effective ways of removing phosphorus upstream are sedimentation, soil accretion, and burial. In basins where SRP is the primary form of phosphorus, biological uptake in floodplain forests is the best way of removing nutrients. Phosphorus can transform between SRP and particulate phosphorus depending on ambient conditions or processes like decomposition, biological uptake, redoximorphic release, and sedimentation and accretion. In either phosphorus form, floodplain forests are beneficial as phosphorus sinks, and

1950-580: The river may abandon the channel belt and build a new one at another position on the floodplain. This process is called avulsion and occurs at intervals of 10–1000 years. Historical avulsions leading to catastrophic flooding include the 1855 Yellow River flood and the 2008 Kosi River flood . Floodplains can form around rivers of any kind or size. Even relatively straight stretches of river are capable of producing floodplains. Mid-channel bars in braided rivers migrate downstream through processes resembling those in point bars of meandering rivers and can build up

2000-605: The river previously followed continues as a steep bluff at the edge of the Wellington Harbour . The Waiwhetu artesian aquifer , sometimes referred to as the Hutt Aquifer, is a pressurized zone of water-retaining sand, gravel and boulders beneath the Hutt Valley and Wellington Harbour which provides about 40% of the public fresh water supply for Lower Hutt and Wellington city. Water flows down into

2050-465: The river to the locality of the present bridge [near the current Ewen Bridge], and the sight of the foliage on the banks at this point, with the white clematis hanging in graceful folds from the lofty branches, was superb. The river being much narrower that it is now, while the valley was under forest, the flood waters would necessarily be held back, and the scour and rush of gravel and sand that has since contributed to widen it did not then prevail to nearly

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2100-511: The river, the successive plant communities are bank vegetation (usually annuals); sedge and reeds; willow shrubs; willow-poplar forest; oak-ash forest; and broadleaf forest. Human disturbance creates wet meadows that replace much of the original ecosystem. The biozones reflect a soil moisture and oxygen gradient that in turn corresponds to a flooding frequency gradient. The primeval floodplain forests of Europe were dominated by oak (60%) elm (20%) and hornbeam (13%), but human disturbance has shifted

2150-418: The river. Levees are typically built up enough to be relatively well-drained compared with nearby wetlands, and levees in non-arid climates are often heavily vegetated. Crevasses are formed by breakout events from the main river channel. The river bank fails, and floodwaters scour a channel. Sediments from the crevasse spread out as delta -shaped deposits with numerous distributary channels. Crevasse formation

2200-410: The same extent. The river was also changed by a major earthquake in 1855 that raised the riverbed. The regular flooding of Lower Hutt resulted in highly fertile land and prior to the building of state housing by the first Labour Government starting in 1937, there were many market gardens in Lower Hutt. Well-established foot tracks along the river were formally signposted in the 1990s, through

2250-444: The same term [REDACTED] This disambiguation page lists articles associated with the title Hutt . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Hutt&oldid=1110384544 " Categories : Disambiguation pages Place name disambiguation pages Hidden categories: Short description

2300-408: The spawning season for fish often coincides with the onset of flooding. Fish must grow quickly during the flood to survive the subsequent drop in water level. As the floodwaters recede, the littoral experiences blooms of microorganisms, while the banks of the river dry out and terrestrial plants germinate to stabilize the bank. The biota of floodplains has high annual growth and mortality rates, which

2350-459: The surrounding grade. Many State and local governments have, in addition, adopted floodplain construction regulations which are more restrictive than those mandated by the NFIP. The US government also sponsors flood hazard mitigation efforts to reduce flood impacts. California 's Hazard Mitigation Program is one funding source for mitigation projects. A number of whole towns such as English, Indiana , have been completely relocated to remove them from

2400-945: The track can be affected by flooding. There are several spots for swimming, fishing and kayaking. The trail includes some filming locations for the Lord of the Rings film franchise. The Lower Hutt Parkrun runs along the last 2.5-kilometre (1.6 mi) section of the Hutt River from just north of the Ewen Bridge down to the Waione Bridge and back. The river has a good stock of brown trout. Heading downstream: 41°14′S 174°54′E  /  41.233°S 174.900°E  / -41.233; 174.900 Floodplain Because of regular flooding, floodplains frequently have high soil-fertility since nutrients are deposited with

2450-672: The upper 30 cm of the soil profile also varies widely based on microtopography which affects oxygen availability. Floodplain soil stays aerated for long stretches of time in between flooding events, but during flooding, saturated soil can become oxygen-depleted if it stands stagnant for long enough. More soil oxygen is available at higher elevations farther from the river. Floodplain forests generally experience alternating periods of aerobic and anaerobic soil microbe activity which affects fine root development and desiccation. Floodplains have high buffering capacity for phosphorus to prevent nutrient loss to river outputs. Phosphorus nutrient loading

2500-449: The west and it is about this point the river starts to flow along the virtually straight Wellington geologic fault , which lies on the western side of the river valley. At the lower end of the Upper Hutt floodplain is Taita Gorge, which separates Upper Hutt from Lower Hutt ; this gorge is significantly shorter and less constricting than Kaitoke Gorge. The river's outflow, at Petone , is into Wellington Harbour . The geological fault that

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