Stream crossing

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This article covers crossings over small streams, not those over large rivers.

Stream crossings are the numerous instances where small perennial or intermittent streams are crossed by roads, pipelines, railways, or any other thing which might restrict the flow of the steam in ordinary or flood conditions. Crossings over any dry channel which might carry flood water is included. Any structure over or in a stream which results in limitations on the movement of fish or other ecological elements can be an issue.

Stream A body of surface water flowing down a channel

A stream is a body of water with surface water flowing within the bed and banks of a channel. The stream encompasses surface and groundwater fluxes that respond to geological, geomorphological, hydrological and biotic controls.

Road A demarcated land route with a suitable surface between places

A road is a thoroughfare, route, or way on land between two places that has been paved or otherwise improved to allow travel by foot or some form of conveyance, including a motor vehicle, cart, bicycle, or horse.

Pipeline transport Mode of transporting fluids over long distances through sealed pipes

Pipeline transport is the long-distance transportation of a liquid or gas through a system of pipes—a pipeline—typically to a market area for consumption. The latest data from 2014 gives a total of slightly less than 2,175,000 miles (3,500,000 km) of pipeline in 120 countries of the world. The United States had 65%, Russia had 8%, and Canada had 3%, thus 75% of all pipeline were in these three countries.

Contents

Types

In addition to bridges and culverts streams may be crossed by fords, floodways, low-water crossings or even stepping stones.

Bridge structure built to span physical obstacles

A bridge is a structure built to span physical obstacles without closing the way underneath such as a body of water, valley, or road, for the purpose of providing passage over the obstacle, usually something that can be detrimental to cross otherwise. There are many different designs that each serve a particular purpose and apply to different situations. Designs of bridges vary depending on the function of the bridge, the nature of the terrain where the bridge is constructed and anchored, the material used to make it, and the funds available to build it.

Culvert Structure that allows the passage of water or organisms under an obstruction

A culvert is a structure that allows water to flow under a road, railroad, trail, or similar obstruction from one side to the other side. 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.

Ford (crossing) crossing in a river

A ford is a shallow place with good footing where a river or stream may be crossed by wading, or inside a vehicle getting its wheels wet. A ford may occur naturally or be constructed. Fords may be impassable during high water. A low water crossing is a low bridge that allows crossing over a river or stream when water is low but may be covered by deep water when the river is high.

Conveyance capacity

Often expressed in cubic feet per second (cfs), conveyance capacity is the amount of water a stream crossing structure will pass. The amount of water that can be predicted during flood conditions, such as a 100-year flood is one design consideration.

100-year flood flood event

A one-hundred-year flood is a flood event that has a 1% probability of occurring in any given year.

Failure to convey

If stream flow exceeds the capacity of the passage through the crossing or it is plugged by debris the crossing may be overtopped or the stream diverted down the road. This may result in substantial erosion as flood water cuts a gully on the side of road. Diversion occurs when a road slopes downward from a crossing and the height of the road exceeds the height of any outlet down the road. A sag (dip) in the road below the crossing may serve as a channel for over flow of excess water and prevent water from continuing down the road but is only practical on gentle slopes. [1]

Erosion Processes which remove soil and rock from one place on the Earths crust, then transport it to another location where it is deposited

In earth science, erosion is the action of surface processes that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice (glaciers), snow, air (wind), plants, animals, and humans. In accordance with these agents, erosion is sometimes divided into water erosion, glacial erosion, snow erosion, wind (aeolic) erosion, zoogenic erosion, and anthropogenic erosion. The particulate breakdown of rock or soil into clastic sediment is referred to as physical or mechanical erosion; this contrasts with chemical erosion, where soil or rock material is removed from an area by its dissolving into a solvent, followed by the flow away of that solution. Eroded sediment or solutes may be transported just a few millimetres, or for thousands of kilometres.

Structural integrity

What happens when a heavy truck passes over, or flood water plugs an opening with debris or overtops the structure.

Habitat continuity

Passage of wildlife, particularly fish such as salmon which spawn in streams, is a design consideration as is habitat continuity. In some jurisdictions, such as Massachusetts, these considerations may be incorporated into stream crossing regulations. [2]

Salmon Family of fish related to trout

Salmon is the common name for several species of ray-finned fish in the family Salmonidae. Other fish in the same family include trout, char, grayling and whitefish. Salmon are native to tributaries of the North Atlantic and Pacific Ocean. Many species of salmon have been introduced into non-native environments such as the Great Lakes of North America and Patagonia in South America. Salmon are intensively farmed in many parts of the world.

The Massachusetts Department of Transportation (MassDOT) oversees roads, public transit, aeronautics, and transportation licensing and registration in the US state of Massachusetts. It was created on November 1, 2009 by the 186th Session of the Massachusetts General Court upon enactment of the 2009 Transportation Reform Act.

See also

Related Research Articles

Flood Overflow of water that submerges land that is not normally submerged

A flood is an overflow of water that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrology and are of significant concern in agriculture, civil engineering and public health.

River Don, Yorkshire river in South Yorkshire, England

The River Don is a river in South Yorkshire and the East Riding of Yorkshire, England. It rises in the Pennines and flows for 70 miles (110 km) eastwards, through the Don Valley, via Penistone, Sheffield, Rotherham, Mexborough, Conisbrough, Doncaster and Stainforth. It originally joined the Trent, but was re-engineered by Cornelius Vermuyden as the Dutch River in the 1620s, and now joins the River Ouse at Goole. Don Valley is the local UK parliamentary constituency near the Doncaster stretch of the river.

Fish ladder structure that allows fish and other organisms to pass artificial or natural barriers at watercourses

A fish ladder, also known as a fishway, fish pass or fish steps, is a structure on or around artificial and natural barriers to facilitate diadromous fishes' natural migration. Most fishways enable fish to pass around the barriers by swimming and leaping up a series of relatively low steps into the waters on the other side. The velocity of water falling over the steps has to be great enough to attract the fish to the ladder, but it cannot be so great that it washes fish back downstream or exhausts them to the point of inability to continue their journey upriver.

Shoalhaven River river in Australia

The Shoalhaven River is a perennial river that rises from the Southern Tablelands and flows into an open mature wave dominated barrier estuary near Nowra on the South Coast of New South Wales, Australia.

Riparian water rights is a system for allocating water among those who possess land along its path. It has its origins in English common law. Riparian water rights exist in many jurisdictions with a common law heritage, such as Canada, Australia, and states in the eastern United States.

Spillway structure for controlled release of flows from a dam or levee

A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically the riverbed of the dammed river itself. In the United Kingdom, they may be known as overflow channels. Spillways ensure that the water does not overflow and damage or destroy the dam.

Wildlife crossing structures that allow animals to cross human-made barriers safely, typically bridges and tunnels

Wildlife crossings are structures that allow animals to cross human-made barriers safely. Wildlife crossings may include: underpass tunnels, viaducts, and overpasses ; amphibian tunnels; fish ladders; Canopy bridge, tunnels and culverts ; green roofs.

River Lymn river in Lincolnshire, United Kingdom

The River Lymn is a river in Lincolnshire, England. It rises in the Wolds on the eastern slope of Castcliffe Hill in Fulletby parish. It flows south-eastwards to the Lincolnshire Marsh, where it becomes known as the Steeping River on the boundary of Great Steeping parish. The main channel is supplemented by the Wainfleet Relief Channel as it passes Wainfleet All Saints, and the relief channel is joined by the old course of the Lymn. Once the two channels rejoin, there are three flood defence structures to protect the region from flooding by the North Sea.

Assabet River river in the United States of America

The Assabet River is a small river about 20 miles (30 km) west of Boston, Massachusetts, United States. The river is 34.4 miles (55.4 km) long. OARS: the Organization for the Assabet, Sudbury and Concord Rivers, headquartered in West Concord, Massachusetts, is a non-profit organization dedicated to the preservation, protection, and enhancement of the natural and recreational features of these three rivers and their watershed. The Assabet and Sudbury Rivers merge in Concord to become the Concord River.

Bonnet Carré Spillway

The Bonnet Carré Spillway is a flood control operation in the Lower Mississippi Valley. Located in St. Charles Parish, Louisiana – about 12 miles (19 km) west of New Orleans – it allows floodwaters from the Mississippi River to flow into Lake Pontchartrain and thence into the Gulf of Mexico. The construction of the Spillway was completed in 1931.

Low-water crossing bridge when the water flow is low

A low-water crossing provides a bridge when water flow is low. Under high-flow conditions, water runs over the roadway and precludes vehicular traffic. This approach is cheaper than building a bridge to raise the level of the road above the highest flood stage of a river, particularly in developing countries or in semi-arid areas with rare high-volume rain. Low-water crossings can be dangerous when flooded.

Blanco River (Texas) river in the Hill Country of Texas, USA

The Blanco River is a river in the Hill Country of Texas in the United States.

Vargas tragedy major natural disaster with torrential rainfall, followed with flash floods and land slides

The Vargas tragedy was a natural disaster that occurred in Vargas State, Venezuela on 14–16 December 1999, when torrential rains caused flash floods and debris flows that killed tens of thousands of people, destroyed thousands of homes, and led to the complete collapse of the state's infrastructure. According to relief workers, the neighborhood of Los Corales was buried under 3 metres (9.8 ft) of mud and a high percentage of homes were simply swept into the ocean. Entire towns including Cerro Grande and Carmen de Uria completely disappeared. As much as 10% of the population of Vargas died during the event.

The River Lee Flood Relief Channel (FRC) is located in the Lea Valley and flows between Ware, Hertfordshire, and Stratford, east London. Work started on the channel in 1947 following major flooding and it was fully operational by 1976. The channel incorporates existing watercourses, lakes and new channels. Water from the channel feeds the Lee Valley Reservoir Chain.

Stream restoration

Stream restoration or river restoration, sometimes called river reclamation in the UK, describes a set of activities that help improve the environmental health of a river or stream. These activities aim to restore the natural state and functioning of the river system in support of biodiversity, recreation, flood management and landscape development.

Bridge scour

Bridge scour is the removal of sediment such as sand and gravel from around bridge abutments or piers. Scour, caused by swiftly moving water, can scoop out scour holes, compromising the integrity of a structure.

Flow device

Flow devices are man-made solutions to beaver-related flooding problems. Traditional solutions have involved the trapping and removal of all the beavers in an area. While this is sometimes necessary, it is typically a short-lived solution, as beaver populations have made a remarkable comeback in the United States and rapidly recolonize suitable habitat. In fact, a 2006 survey found that trapping as a solution to beaver problems had a 79% failure rate within two years due to resettlement by new beavers. Flow devices are relatively cost-effective, low-maintenance solutions that regulate the water level of beaver dams and keep culverts open. A 2006 study by the Virginia Department of Transportation found that for every $1 spent on flow-device installation relative to historical preventive maintenance, road repairs, and beaver population control activities, $8 was saved, for a return on investment of nearly 8:1.

A detention dam is a dam built to catch surface runoff and stream water flow to regulate the water flow in areas below the dam. Detention dams are commonly used to reduce the damage caused by flooding or to manage the flow rate through a channel. Detention dams can also be constructed to replenish groundwater and trap sediment. Detention dams are one of three classifications of dams: storage dams, diversion dams, and detention dams. Storage dams store water for extended times for irrigation, livestock, municipal water supply, recreation, and hydroelectric power generation. Diversion dams raise the water level to redirect the water to a designated location. The diverted water typically supplies irrigation systems or reservoirs.

Eller Beck

Eller Beck is a small river in North Yorkshire, England, which flows through the town of Skipton and is a tributary of the River Aire. Its channel was heavily modified to supply water for milling in the eighteenth and nineteenth centuries, and although all milling has ceased, the water now supplies power to the National Grid, generated by a turbine at High Corn Mill. There are several underground culverts within the town, and these contribute to the flood risk. In order to alleviate flooding in Skipton town centre, a scheme involving two flood water storage reservoirs has been designed, but the start of the work to implement it was delayed in October 2014 by a shortfall in funding for the project.

References

  1. Michael J. Furniss; Michael Love; Sam A. Flanagan (December 1997). "Diversion Potential at Road-Stream Crossings". fs.fed.us/. U.S. Forest Service. Retrieved April 29, 2018.
  2. MassDOT personnel (December 2010). "Design of Bridges and Culverts for Wildlife Passage at Freshwater Streams" (PDF). MassDOT, Massachusetts Department of Transportation. State of Massachusetts. Retrieved April 28, 2018.

Further reading

The Nature Conservancy organization

The Nature Conservancy (TNC) is a charitable environmental organization, headquartered in Arlington, Virginia, United States.