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98-567: The Lieutenant William F. Callahan Jr. Tunnel (colloquially Callahan Tunnel ) is one of four tunnels , and one of three road tunnels, beneath Boston Harbor in Boston, Massachusetts . It carries motor vehicles from the North End to Logan International Airport and Route 1A in East Boston . Ordinarily, this tunnel is only used to carry traffic out of the city, and with the completion of

196-695: A canal . The central portions of a rapid transit network are usually in the tunnel. Some tunnels are used as sewers or aqueducts to supply water for consumption or for hydroelectric stations. Utility tunnels are used for routing steam, chilled water, electrical power or telecommunication cables, as well as connecting buildings for convenient passage of people and equipment. Secret tunnels are built for military purposes, or by civilians for smuggling of weapons , contraband , or people . Special tunnels, such as wildlife crossings , are built to allow wildlife to cross human-made barriers safely. Tunnels can be connected together in tunnel networks . A tunnel

294-526: A $ 50 fine. As the signals are almost always yellow, this rule is universally ignored by drivers. Other markings in the tunnel include a "double white line" in the center, intended to discourage drivers from changing lanes, to be penalized with a $ 100 fine. The Callahan Tunnel was repaired in the 1990s. A major overhaul began in December 2013, which completely replaced the deck, curbs, and wall panels; and cleaned and repaired its ceiling and vent systems (above

392-425: A depth of about 3 to 6 feet (0.91 to 1.83 m). To protect pipes from impact , abrasion , and corrosion , a variety of methods are used. These can include wood lagging (wood slats), concrete coating, rockshield, high-density polyethylene , imported sand padding, sacrificial cathodes and padding machines. Crude oil contains varying amounts of paraffin wax and in colder climates wax buildup may occur within

490-701: A discount is in effect using an E-ZPass transponder, costing $ 0.20. Traffic flowing between Logan International Airport and directions south of the city on I-93 and west of the city on the Massachusetts Turnpike (I-90) normally uses the Ted Williams Tunnel rather than the Callahan and Sumner Tunnels. Airport traffic can also use East Boston surface roads to and from Chelsea ( Chelsea Street Bridge ), Revere ( Massachusetts Route 1A ) and Winthrop ( Massachusetts Route 145 ). The tunnel

588-589: A distinction is made between a "flowline" and a pipeline. The former is an intrafield pipeline, in the sense that it is used to connect subsea wellheads , manifolds and the platform within a particular development field. The latter, sometimes referred to as an "export pipeline", is used to bring the resource to shore. The construction and maintenance of marine pipelines imply logistical challenges that are different from those onland, mainly because of wave and current dynamics, along with other geohazards . In Nigeria oil pipelines get bored by thieves, in 2022, during

686-471: A fuel in oil fields to heat various facilities used by the oil drillers or equipment and trucks used in the oil patch. EG: Propane will convert from a gas to a liquid under light pressure, 100 psi, give or take depending on temperature, and is pumped into cars and trucks at less than 125 psi (860 kPa) at retail stations. Pipelines and rail cars use about double that pressure to pump at 250 psi (1,700 kPa). The distance to ship propane to markets

784-449: A large factor in the decision making process. Civil engineers usually use project management techniques for developing a major structure. Understanding the amount of time the project requires, and the amount of labor and materials needed is a crucial part of project planning. The project duration must be identified using a work breakdown structure and critical path method . Also, the land needed for excavation and construction staging, and

882-467: A pipe jack, with the span of some box jacks in excess of 20 metres (66 ft). A cutting head is normally used at the front of the box being jacked, and spoil removal is normally by excavator from within the box. Recent developments of the Jacked Arch and Jacked deck have enabled longer and larger structures to be installed to close accuracy. There are also several approaches to underwater tunnels,

980-542: A pipeline is currently being constructed from North Dakota to Illinois, commonly known as the Dakota Access Pipeline . As more North American pipelines are built, even more exports of LNG, propane, butane, and other natural gas products occur on all three US coasts. To give insight, North Dakota Bakken region's oil production has grown by 600% from 2007 to 2015. North Dakota oil companies are shipping huge amounts of oil by tanker rail car as they can direct

1078-452: A pipeline system are: Since oil and gas pipelines are an important asset of the economic development of almost any country, it has been required either by government regulations or internal policies to ensure the safety of the assets, and the population and environment where these pipelines run. Pipeline companies face government regulation, environmental constraints and social situations. Government regulations may define minimum staff to run

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1176-501: A pipeline. Often these pipelines are inspected and cleaned using pigging , the practice of using devices known as "pigs" to perform various maintenance operations on a pipeline. The devices are also known as "scrapers" or "Go-devils". "Smart pigs" (also known as "intelligent" or "intelligence" pigs) are used to detect anomalies in the pipe such as dents, metal loss caused by corrosion, cracking or other mechanical damage. These devices are launched from pig-launcher stations and travel through

1274-500: A presently rated 250,000 barrels equivalent per day pipeline, it will be expanded to between 1.0 and 1.3 million barrels per day. It will bring western oil to refineries in Ontario, Michigan, Ohio, Pennsylvania, Quebec and New York by early 2014. New Brunswick will also refine some of this western Canadian crude and export some crude and refined oil to Europe from its deep water oil ULCC loading port. Although pipelines can be built under

1372-449: A problem for pipeline companies. In this case, the detection levels should be under two percent of maximum flow, with a high expectation for location accuracy. Various technologies and strategies have been implemented for monitoring pipelines, from physically walking the lines to satellite surveillance. The most common technology to protect pipelines from occasional leaks is Computational Pipeline Monitoring or CPM. CPM takes information from

1470-462: A set of screens or Human Machine Interface , showing the operational conditions of the pipeline. The operator can monitor the hydraulic conditions of the line, as well as send operational commands (open/close valves, turn on/off compressors or pumps, change setpoints, etc.) through the SCADA system to the field. To optimize and secure the operation of these assets, some pipeline companies are using what

1568-421: A specialized method called clay-kicking for digging tunnels in clay-based soils. The clay-kicker lies on a plank at a 45-degree angle away from the working face and rather than a mattock with his hands, inserts with his feet a tool with a cup-like rounded end, then turns the tool with his hands to extract a section of soil, which is then placed on the waste extract. Clay-kicking is a specialized method developed in

1666-434: A tube can be sunk into a body of water, which is called an immersed tunnel. Cut-and-cover is a simple method of construction for shallow tunnels where a trench is excavated and roofed over with an overhead support system strong enough to carry the load of what is to be built above the tunnel. There are two basic forms of cut-and-cover tunnelling: Shallow tunnels are often of the cut-and-cover type (if under water, of

1764-747: A tunnel than a sufficiently strong bridge). Some water crossings are a mixture of bridges and tunnels, such as the Denmark to Sweden link and the Chesapeake Bay Bridge-Tunnel in Virginia . There are particular hazards with tunnels, especially from vehicle fires when combustion gases can asphyxiate users, as happened at the Gotthard Road Tunnel in Switzerland in 2001. One of the worst railway disasters ever,

1862-432: A tunnel. Bridges usually require a larger footprint on each shore than tunnels. In areas with expensive real estate, such as Manhattan and urban Hong Kong , this is a strong factor in favor of a tunnel. Boston's Big Dig project replaced elevated roadways with a tunnel system to increase traffic capacity, hide traffic, reclaim land, redecorate, and reunite the city with the waterfront. The 1934 Queensway Tunnel under

1960-649: Is a 525-kilometre (326 mi) slurry pipeline which is planned to transport iron ore from the Minas-Rio mine (producing 26.5 million tonnes per year) to the Port of Açu in Brazil. An existing example is the 85-kilometre (53 mi) Savage River Slurry pipeline in Tasmania , Australia, possibly the world's first when it was built in 1967. It includes a 366-metre (1,201 ft) bridge span at 167 metres (548 ft) above

2058-644: Is a TransCanada natural gas line going north across the Niagara region bridges. This gas line carries Marcellus shale gas from Pennsylvania and other tied in methane or natural gas sources into the Canadian province of Ontario. It began operations in the fall of 2012, supplying 16 percent of all the natural gas used in Ontario. This new US-supplied natural gas displaces the natural gas formerly shipped to Ontario from western Canada in Alberta and Manitoba, thus dropping

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2156-521: Is allowed in this tunnel tube, and motorcyclists are directed to the other tube. Each level was built with a three-lane roadway, but only two lanes per level are used – the third serves as a hard shoulder within the tunnel. The A86 Duplex is Europe's longest double-deck tunnel. Pipeline transport Pipeline and Gas Journal' s worldwide survey figures indicate that 118,623 miles (190,905 km) of pipelines are planned and under construction. Of these, 88,976 miles (143,193 km) represent projects in

2254-547: Is an underground or undersea passageway. It is dug through surrounding soil, earth or rock, or laid under water, and is usually completely enclosed except for the two portals common at each end, though there may be access and ventilation openings at various points along the length. A pipeline differs significantly from a tunnel, though some recent tunnels have used immersed tube construction techniques rather than traditional tunnel boring methods. A tunnel may be for foot or vehicular road traffic , for rail traffic, or for

2352-467: Is called "Advanced Pipeline Applications", which are software tools installed on top of the SCADA system, that provide extended functionality to perform leak detection, leak location, batch tracking (liquid lines), pig tracking, composition tracking, predictive modeling, look ahead modeling, and operator training. Pipeline networks are composed of several pieces of equipment that operate together to move products from location to location. The main elements of

2450-505: Is intended to carry both the Istanbul metro and a two-level highway, over a length of 6.5 km (4.0 miles). The French A86 Duplex Tunnel  [ fr ] in west Paris consists of two bored tunnel tubes, the eastern one of which has two levels for light motorized vehicles, over a length of 10 km (6.2 miles). Although each level offers a physical height of 2.54 m (8.3 ft), only traffic up to 2 m (6.6 ft) tall

2548-503: Is less efficient to produce and transport due to greater heat losses. Heat transfer oils are generally not used for economic and ecological reasons. The typical annual loss of thermal energy through distribution is around 10%, as seen in Norway's district heating network. District heating pipelines are normally installed underground, with some exceptions. Within the system, heat storage may be installed to even out peak load demands. Heat

2646-445: Is moved through the pipelines by pump stations along the pipeline. Natural gas (and similar gaseous fuels) are pressurized into liquids known as natural gas liquids (NGLs). Natural gas pipelines are constructed of carbon steel . Hydrogen pipeline transport is the transportation of hydrogen through a pipe. Pipelines are one of the safest ways of transporting materials as compared to road or rail, and hence in war, pipelines are often

2744-625: Is much shorter, as thousands of natural-gas processing plants are located in or near oil fields. Many Bakken Basin oil companies in North Dakota, Montana, Manitoba and Saskatchewan gas fields separate the NGLs in the field, allowing the drillers to sell propane directly to small wholesalers, eliminating the large refinery control of product and prices for propane or butane. The most recent major pipeline to start operating in North America

2842-686: Is odorless unless mixed with a mercaptan odorant where required by a regulating authority. A major ammonia pipeline is the Ukrainian Transammiak line connecting the TogliattiAzot facility in Russia to the exporting Black Sea -port of Odesa . Pipelines have been used for transportation of ethanol in Brazil, and there are several ethanol pipeline projects in Brazil and the United States. The main problems related to

2940-431: Is over 2,800 kilometres (1,700 mi) long, and is connected to wells tapping an aquifer over 500 metres (1,600 ft) underground. District heating or teleheating systems consist of a network of insulated feed and return pipes which transport heated water, pressurized hot water , or sometimes steam to the customer. While steam is hottest and may be used in industrial processes due to its higher temperature, it

3038-494: Is relatively long and narrow; the length is often much greater than twice the diameter , although similar shorter excavations can be constructed, such as cross passages between tunnels. The definition of what constitutes a tunnel can vary widely from source to source. For example, in the United Kingdom, a road tunnel is defined as "a subsurface highway structure enclosed for a length of 150 metres (490 ft) or more." In

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3136-401: Is sometimes necessary during the excavation of a tunnel. They are usually circular and go straight down until they reach the level at which the tunnel is going to be built. A shaft normally has concrete walls and is usually built to be permanent. Once the access shafts are complete, TBMs are lowered to the bottom and excavation can start. Shafts are the main entrance in and out of the tunnel until

3234-609: Is still in operation. As of 2004 , there are 900 miles (1,400 km) of low pressure hydrogen pipelines in the US and 930 miles (1,500 km) in Europe. Two millennia ago, the ancient Romans made use of large aqueducts to transport water from higher elevations by building the aqueducts in graduated segments that allowed gravity to push the water along until it reached its destination. Hundreds of these were built throughout Europe and elsewhere, and along with flour mills were considered

3332-515: Is that the open building pit is muted after tunnel construction; no roof is placed. Some tunnels are double-deck, for example, the two major segments of the San Francisco–Oakland Bay Bridge (completed in 1936) are linked by a 160-metre (540 ft) double-deck tunnel section through Yerba Buena Island , the largest-diameter bored tunnel in the world. At construction this was a combination bidirectional rail and truck pathway on

3430-698: Is the Siloam Tunnel , built in Jerusalem by the kings of Judah around the 8th century BC. Another tunnel excavated from both ends, maybe the second known, is the Tunnel of Eupalinos , which is a tunnel aqueduct 1,036 m (3,400 ft) long running through Mount Kastro in Samos , Greece. It was built in the 6th century BC to serve as an aqueduct . In Ethiopia , the Siqurto foot tunnel , hand-hewn in

3528-405: Is the most desirable option, but ethanol's affinity for water and solvent properties require the use of a dedicated pipeline, or significant cleanup of existing pipelines. Slurry pipelines are sometimes used to transport coal or ore from mines. The material to be transported is closely mixed with water before being introduced to the pipeline; at the far end, the material must be dried. One example

3626-609: Is transferred into the central heating of the dwellings through heat exchangers at heat substations , without mixing of the fluids in either system. Bars in the Veltins-Arena , a major football ground in Gelsenkirchen , Germany, are interconnected by a 5-kilometre (3.1 mi) long beer pipeline. In Randers city in Denmark, the so-called Thor Beer pipeline was operated. Originally, copper pipes ran directly from

3724-528: Is usually known as the "Main Control Room". In this center, all the data related to field measurement is consolidated in one central database. The data is received from multiple RTUs along the pipeline. It is common to find RTUs installed at every station along the pipeline. The SCADA system at the Main Control Room receives all the field data and presents it to the pipeline operator through

3822-569: The Balvano train disaster , was caused by a train stalling in the Armi tunnel in Italy in 1944, killing 426 passengers. Designers try to reduce these risks by installing emergency ventilation systems or isolated emergency escape tunnels parallel to the main passage. Government funds are often required for the creation of tunnels. When a tunnel is being planned or constructed, economics and politics play

3920-590: The Big Dig it only collects traffic from I-93 southbound (right after traffic merges from Storrow Drive) and downtown Boston; northbound traffic uses the Ted Williams Tunnel . As of 2016, a toll of $ 1.50 is charged for non-commercial two-axle vehicles with a Massachusetts E-ZPass, while non-Massachusetts E-ZPass holders are charged $ 1.75. Vehicles without E-ZPass are charged $ 2.05 through MassDOT's Pay By Plate MA program. For residents of certain Boston ZIP codes,

4018-744: The FERC and others, reviews proposed pipeline projects in order to comply with the Clean Water Act , the National Environmental Policy Act , other laws and, in some cases, municipal laws. The Biden administration has sought to permit the respective states and tribal groups to appraise and potentially block the proposed projects. Field devices are instrumentation, data gathering units and communication systems. The field instrumentation includes flow, pressure, and temperature gauges/transmitters, and other devices to measure

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4116-471: The Port Authority of New York and New Jersey was not aware of this bill and had not asked for a grant for such a project. Increased taxes to finance a large project may cause opposition. Tunnels are dug in types of materials varying from soft clay to hard rock. The method of tunnel construction depends on such factors as the ground conditions, the groundwater conditions, the length and diameter of

4214-848: The Queens-Midtown Tunnel between Manhattan and the borough of Queens on Long Island ; the Detroit-Windsor Tunnel between Michigan and Ontario ; and the Elizabeth River tunnels between Norfolk and Portsmouth, Virginia ; the 1934 River Mersey road Queensway Tunnel ; the Western Scheldt Tunnel , Zeeland, Netherlands; and the North Shore Connector tunnel in Pittsburgh, Pennsylvania . The Sydney Harbour Tunnel

4312-472: The River Mersey at Liverpool was chosen over a massively high bridge partly for defense reasons; it was feared that aircraft could destroy a bridge in times of war, not merely impairing road traffic but blocking the river to navigation. Maintenance costs of a massive bridge to allow the world's largest ships to navigate under were considered higher than for a tunnel. Similar conclusions were reached for

4410-679: The United Kingdom of digging tunnels in strong clay-based soil structures. This method of cut and cover construction required relatively little disturbance of property during the renewal of the United Kingdom's then ancient sewerage systems. It was also used during the First World War by Royal Engineer tunnelling companies placing mines beneath German lines, because it was almost silent and so not susceptible to listening methods of detection. Tunnel boring machines (TBMs) and associated back-up systems are used to highly automate

4508-610: The canton of Glarus . The borehole has a diameter of 8.03 metres (26.3 ft). The four TBMs used for excavating the 57-kilometre (35 mi) Gotthard Base Tunnel , in Switzerland , had a diameter of about 9 metres (30 ft). A larger TBM was built to bore the Green Heart Tunnel (Dutch: Tunnel Groene Hart) as part of the HSL-Zuid in the Netherlands, with a diameter of 14.87 metres (48.8 ft). This in turn

4606-489: The water table . This pressurizes the ground ahead of the TBM cutter head to balance the water pressure. The operators work in normal air pressure behind the pressurized compartment, but may occasionally have to enter that compartment to renew or repair the cutters. This requires special precautions, such as local ground treatment or halting the TBM at a position free from water. Despite these difficulties, TBMs are now preferred over

4704-689: The 16th century as a metaphor for a narrow, confined space like the inside of a cask. Some of the earliest tunnels used by humans were paleoburrows excavated by prehistoric mammals. Much of the early technology of tunneling evolved from mining and military engineering . The etymology of the terms "mining" (for mineral extraction or for siege attacks ), " military engineering ", and " civil engineering " reveals these deep historic connections. Predecessors of modern tunnels were adits that transported water for irrigation , drinking, or sewerage . The first qanats are known from before 2000 BC. The earliest tunnel known to have been excavated from both ends

4802-638: The 1960s. The main idea of this method is to use the geological stress of the surrounding rock mass to stabilize the tunnel, by allowing a measured relaxation and stress reassignment into the surrounding rock to prevent full loads becoming imposed on the supports. Based on geotechnical measurements, an optimal cross section is computed. The excavation is protected by a layer of sprayed concrete, commonly referred to as shotcrete . Other support measures can include steel arches, rock bolts, and mesh. Technological developments in sprayed concrete technology have resulted in steel and polypropylene fibers being added to

4900-716: The 1971 Kingsway Tunnel under the Mersey. In Hampton Roads, Virginia , tunnels were chosen over bridges for strategic considerations; in the event of damage, bridges might prevent US Navy vessels from leaving Naval Station Norfolk . Water-crossing tunnels built instead of bridges include the Seikan Tunnel in Japan; the Holland Tunnel and Lincoln Tunnel between New Jersey and Manhattan in New York City ;

4998-709: The Middle Ages, crosses a mountain ridge. In the Gaza Strip , the network of tunnels was used by Jewish strategists as rock-cut shelters, in first links to Judean resistance against Roman rule in the Bar Kokhba revolt during the 2nd century AD. A major tunnel project must start with a comprehensive investigation of ground conditions by collecting samples from boreholes and by other geophysical techniques. An informed choice can then be made of machinery and methods for excavation and ground support, which will reduce

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5096-471: The Russian-Ukrainian war, the submarine natural gas pipelines Nord Stream I and II got blasted. In general, pipelines can be classified in three categories depending on purpose: When a pipeline is built, the construction project not only covers the civil engineering work to lay the pipeline and build the pump/compressor stations, it also has to cover all the work related to the installation of

5194-598: The Savage River. Hydrogen pipeline transport is a transportation of hydrogen through a pipe as part of the hydrogen infrastructure . Hydrogen pipeline transport is used to connect the point of hydrogen production or delivery of hydrogen with the point of demand, with transport costs similar to CNG , the technology is proven. Most hydrogen is produced at the place of demand with every 50 to 100 miles (160 km) an industrial production facility. The 1938 Rhine-Ruhr 240-kilometre (150 mi) hydrogen pipeline

5292-533: The US. The distance from the biggest oil patch in North Dakota, in Williston, North Dakota , is only about 85 miles or 137 kilometers to the Canada–US border and Manitoba . Mutual funds and joint ventures are the largest investors in new oil and gas pipelines. In the fall of 2012, the US began exporting propane to Europe, known as LPG, as wholesale prices there are much higher than in North America. Additionally,

5390-554: The United States, 70% of crude oil and petroleum products are shipped by pipeline. (23% are by ship, 4% by truck, and 3% by rail) In Canada for natural gas and petroleum products, 97% are shipped by pipeline. Natural gas (and similar gaseous fuels) are lightly pressurized into liquids known as Natural Gas Liquids (NGLs). Small NGL processing facilities can be located in oil fields so the butane and propane liquid under light pressure of 125 pounds per square inch (860 kPa), can be shipped by rail, truck or pipeline. Propane can be used as

5488-536: The United States, the NFPA definition of a tunnel is "An underground structure with a design length greater than 23 m (75 ft) and a diameter greater than 1,800 millimetres (5.9 ft)." The word "tunnel" comes from the Middle English tonnelle , meaning "a net", derived from Old French tonnel , a diminutive of tonne ("cask"). The modern meaning, referring to an underground passageway, evolved in

5586-400: The blocky nature of rocks, the exact location of fault zones, or the stand-up times of softer ground. This may be a particular concern in large-diameter tunnels. To give more information, a pilot tunnel (or "drift tunnel") may be driven ahead of the main excavation. This smaller tunnel is less likely to collapse catastrophically should unexpected conditions be met, and it can be incorporated into

5684-592: The brewery, but when the brewery moved out of the city in the 1990s, Thor Beer replaced it with a giant tank. A three-kilometer beer pipeline was completed in Bruges , Belgium in September 2016 to reduce truck traffic on the city streets. The village of Hallstatt in Austria, which is known for its long history of salt mining , claims to contain "the oldest industrial pipeline in the world", dating back to 1595. It

5782-456: The ceiling and below the deck). It was planned for three phases: complete closure from December 27, 2013 to March 12, 2014 during deck and curb replacement; closures 11pm-5am from March 13, 2014 to late August 2014 for wall panel replacement; and final work until November 2014. McCourt Construction of South Boston was awarded the $ 19.3 million contract in August. During closures, Logan-bound traffic

5880-502: The concrete mix to improve lining strength. This creates a natural load-bearing ring, which minimizes the rock's deformation . By special monitoring the NATM method is flexible, even at surprising changes of the geomechanical rock consistency during the tunneling work. The measured rock properties lead to appropriate tools for tunnel strengthening . In pipe jacking , hydraulic jacks are used to push specially made pipes through

5978-609: The economic downturn in 2008. After faltering in 2009, demand for pipeline expansion and updating increased the following year as energy production grew. By 2012, almost 32,000 miles (51500 km) of North American pipeline were being planned or under construction. When pipelines are constrained, additional pipeline product transportation options may include the use of drag reducing agents, or by transporting product via truck or rail. Oil pipelines are made from steel or plastic tubes with inner diameter typically from 4 to 48 inches (100 to 1,220 mm). Most pipelines are typically buried at

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6076-409: The entire tunnelling process, reducing tunnelling costs. In certain predominantly urban applications, tunnel boring is viewed as a quick and cost-effective alternative to laying surface rails and roads. Expensive compulsory purchase of buildings and land, with potentially lengthy planning inquiries, is eliminated. Disadvantages of TBMs arise from their usually large size – the difficulty of transporting

6174-513: The field devices that will support remote operation. The pipeline is routed along what is known as a "right of way". Pipelines are generally developed and built using the following stages: Russia has "Pipeline Troops" as part of the Rear Services , who are trained to build and repair pipelines. Russia is the only country to have Pipeline Troops. The U.S. government, mainly through the EPA ,

6272-441: The final tunnel or used as a backup or emergency escape passage. Alternatively, horizontal boreholes may sometimes be drilled ahead of the advancing tunnel face. Other key geotechnical factors: For water crossings, a tunnel is generally more costly to construct than a bridge. However, both navigational and traffic considerations may limit the use of high bridges or drawbridges intersecting with shipping channels, necessitating

6370-437: The generation of suction pressure for useful work and in transporting solid objects. Pipelines are useful for transporting water for drinking or irrigation over long distances when it needs to move over hills , or where canals or channels are poor choices due to considerations of evaporation , pollution , or environmental impact. Oil pipelines are made from steel or plastic tubes which are usually buried. The oil

6468-588: The government regulated pipeline shipping charges because of the significantly shorter distance from gas source to consumer. To avoid delays and US government regulation, many small, medium and large oil producers in North Dakota have decided to run an oil pipeline north to Canada to meet up with a Canadian oil pipeline shipping oil from west to east. This allows the Bakken Basin and Three Forks oil producers to get higher negotiated prices for their oil because they will not be restricted to just one wholesale market in

6566-405: The ground behind a TBM or shield. This method is commonly used to create tunnels under existing structures, such as roads or railways. Tunnels constructed by pipe jacking are normally small diameter bores with a maximum size of around 3.2 metres (10 ft). Box jacking is similar to pipe jacking, but instead of jacking tubes, a box-shaped tunnel is used. Jacked boxes can be a much larger span than

6664-640: The immersed-tube type), while deep tunnels are excavated, often using a tunnelling shield . For intermediate levels, both methods are possible. Large cut-and-cover boxes are often used for underground metro stations, such as Canary Wharf tube station in London. This construction form generally has two levels, which allows economical arrangements for ticket hall, station platforms, passenger access and emergency egress, ventilation and smoke control, staff rooms, and equipment rooms. The interior of Canary Wharf station has been likened to an underground cathedral, owing to

6762-435: The inevitable smoke and steam. A major disadvantage of cut-and-cover is the widespread disruption generated at the surface level during construction. This, and the availability of electric traction, brought about London Underground's switch to bored tunnels at a deeper level towards the end of the 19th century. Prior to the replacement of manual excavation by the use of boring machines, Victorian tunnel excavators developed

6860-468: The large TBM to the site of tunnel construction, or (alternatively) the high cost of assembling the TBM on-site, often within the confines of the tunnel being constructed. There are a variety of TBM designs that can operate in a variety of conditions, from hard rock to soft water-bearing ground. Some TBMs, the bentonite slurry and earth-pressure balance types, have pressurized compartments at the front end, allowing them to be used in difficult conditions below

6958-466: The lifeline of the Roman Empire. The ancient Chinese also made use of channels and pipe systems for public works. The famous Han dynasty court eunuch Zhang Rang (d. 189 AD) once ordered the engineer Bi Lan to construct a series of square-pallet chain pumps outside the capital city of Luoyang . These chain pumps serviced the imperial palaces and living quarters of the capital city as

7056-629: The lower deck with automobiles above, now converted to one-way road vehicle traffic on each deck. In Turkey, the Eurasia Tunnel under the Bosphorus , opened in 2016, has at its core a 5.4 km (3.4 miles) two-deck road tunnel with two lanes on each deck. Additionally, in 2015 the Turkish government announced that it will build three -level tunnel, also under the Bosporus. The tunnel

7154-416: The mainland. In 1994, the pipeline was abandoned. In places, a pipeline may have to cross water expanses, such as small seas, straits and rivers. In many instances, they lie entirely on the seabed. These pipelines are referred to as "marine" pipelines (also, "submarine" or "offshore" pipelines). They are used primarily to carry oil or gas, but transportation of water is also important. In offshore projects,

7252-413: The most economical way to transport large quantities of oil, refined oil products or natural gas over land. For example, in 2014, pipeline transport of crude oil cost about $ 5 per barrel, while rail transport cost about $ 10 to $ 15 per barrel. Trucking has even higher costs due to the additional labor required; employment on completed pipelines represents only "1% of that of the trucking industry.". In

7350-526: The oil to the market that gives the best price, and rail cars can be used to avoid a congested oil pipeline to get the oil to a different pipeline in order to get the oil to market faster or to a different less busy oil refinery. However, pipelines provide a cheaper means to transport by volume. Enbridge in Canada is applying to reverse an oil pipeline going from east-to-west (Line 9) and expanding it and using it to ship western Canadian bitumen oil eastward. From

7448-483: The older method of tunnelling in compressed air, with an airlock/decompression chamber some way back from the TBM, which required operators to work in high pressure and go through decompression procedures at the end of their shifts, much like deep-sea divers . In February 2010, Aker Wirth delivered a TBM to Switzerland, for the expansion of the Linth–Limmern Power Stations located south of Linthal in

7546-540: The operation of empty and loaded trains at the same time. The temporary way is replaced by the permanent way at completion, thus explaining the term " Perway ". The vehicles or traffic using a tunnel can outgrow it, requiring replacement or enlargement: An open building pit consists of a horizontal and a vertical boundary that keeps groundwater and soil out of the pit. There are several potential alternatives and combinations for (horizontal and vertical) building pit boundaries. The most important difference with cut-and-cover

7644-451: The operation, operator training requirements, pipeline facilities, technology and applications required to ensure operational safety. For example, in the State of Washington it is mandatory for pipeline operators to be able to detect and locate leaks of 8 percent of maximum flow within fifteen minutes or less. Social factors also affect the operation of pipelines. Product theft is sometimes also

7742-740: The overall project duration and reduce cost. These techniques were also used for the Callahan Tunnel Rehabilitation Project. In 2016, cashless tolling systems were installed in both directions, entering the Sumner Tunnel and exiting the Callahan Tunnel as part of a plan to modernize toll collection the Boston area. 42°22′04″N 71°2′46″W  /  42.36778°N 71.04611°W  / 42.36778; -71.04611 Tunnel A tunnel

7840-422: The pipeline to be received at any other station down-stream, either cleaning wax deposits and material that may have accumulated inside the line or inspecting and recording the condition of the line. For natural gas, pipelines are constructed of carbon steel and vary in size from 2 to 60 inches (51 to 1,524 mm) in diameter, depending on the type of pipeline. The gas is pressurized by compressor stations and

7938-503: The planning and design phase; 29,647 miles (47,712 km) reflect pipelines in various stages of construction. Liquids and gases are transported in pipelines, and any chemically stable substance can be sent through a pipeline. Pipelines exist for the transport of crude and refined petroleum, fuels – such as oil, natural gas and biofuels – and other fluids including sewage , slurry , water , beer , hot water or steam for shorter distances and even pneumatic systems which allow for

8036-522: The project is completed. If a tunnel is going to be long, multiple shafts at various locations may be bored so that entrance to the tunnel is closer to the unexcavated area. Once construction is complete, construction access shafts are often used as ventilation shafts , and may also be used as emergency exits. The New Austrian Tunnelling method (NATM)—also referred to as the Sequential Excavation Method (SEM) —was developed in

8134-490: The proper machinery must be selected. Large infrastructure projects require millions or even billions of dollars, involving long-term financing, usually through issuance of bonds . The costs and benefits for an infrastructure such as a tunnel must be identified. Political disputes can occur, as in 2005 when the US House of Representatives approved a $ 100 million federal grant to build a tunnel under New York Harbor. However,

8232-584: The relevant data required. These instruments are installed along the pipeline on some specific locations, such as injection or delivery stations, pump stations (liquid pipelines) or compressor stations (gas pipelines), and block valve stations. The information measured by these field instruments is then gathered in local remote terminal units (RTU) that transfer the field data to a central location in real time using communication systems, such as satellite channels, microwave links, or cellular phone connections. Pipelines are controlled and operated remotely, from what

8330-482: The risk of encountering unforeseen ground conditions. In planning the route, the horizontal and vertical alignments can be selected to make use of the best ground and water conditions. It is common practice to locate a tunnel deeper than otherwise would be required, in order to excavate through solid rock or other material that is easier to support during construction. Conventional desk and preliminary site studies may yield insufficient information to assess such factors as

8428-445: The sea, that process is economically and technically demanding, so the majority of oil at sea is transported by tanker ships . Similarly, it is often more economically feasible to transport natural gas in the form of LNG, however the break-even point between LNG and pipelines would depend on the volume of natural gas and the distance it travels. The market size for oil and gas pipeline construction experienced tremendous growth prior to

8526-542: The sheer size of the excavation. This contrasts with many traditional stations on London Underground , where bored tunnels were used for stations and passenger access. Nevertheless, the original parts of the London Underground network, the Metropolitan and District Railways, were constructed using cut-and-cover. These lines pre-dated electric traction and the proximity to the surface was useful to ventilate

8624-615: The target of military attacks. It is well documented when the first crude oil pipeline was built. Credit for the development of pipeline transport belongs indisputably to the Oil Transport Association, which first constructed a 2-inch (51 mm) wrought iron pipeline over a 6-mile (9.7 km) track from an oil field in Pennsylvania to a railroad station in Oil Creek , in the 1860s. Pipelines are generally

8722-462: The transport of ethanol by pipeline are its corrosive nature and tendency to absorb water and impurities in pipelines, which are not problems with oil and natural gas. Insufficient volumes and cost-effectiveness are other considerations limiting construction of ethanol pipelines. In the US minimal amounts of ethanol are transported by pipeline. Most ethanol is shipped by rail, the main alternatives being truck and barge. Delivering ethanol by pipeline

8820-400: The tunnel drive, the depth of the tunnel, the logistics of supporting the tunnel excavation, the final use and the shape of the tunnel and appropriate risk management. There are three basic types of tunnel construction in common use. Cut-and-cover tunnels are constructed in a shallow trench and then covered over. Bored tunnels are constructed in situ, without removing the ground above. Finally,

8918-428: The two most common being bored tunnels or immersed tubes , examples are Bjørvika Tunnel and Marmaray . Submerged floating tunnels are a novel approach under consideration; however, no such tunnels have been constructed to date. During construction of a tunnel it is often convenient to install a temporary railway, particularly to remove excavated spoil , often narrow gauge so that it can be double track to allow

9016-557: The water lifted by the chain pumps was brought in by a stoneware pipe system. Pipelines are useful for transporting water for drinking or irrigation over long distances when it needs to move over hills , or where canals or channels are poor choices due to considerations of evaporation , pollution , or environmental impact. The 530 km (330 miles) Goldfields Water Supply Scheme in Western Australia using 750 mm (30 inch) pipe and completed in 1903

9114-509: Was constructed from 13,000 hollowed-out tree trunks to transport brine 40 kilometres (25 mi) from Hallstatt to Ebensee . Between 1978 and 1994, a 15 km milk pipeline ran between the Dutch island of Ameland and Holwerd on the mainland, of which 8 km was beneath the Wadden Sea . Every day, 30,000 litres of milk produced on the island were transported to be processed on

9212-575: Was constructed to provide a second harbour crossing and to alleviate traffic congestion on the Sydney Harbour Bridge , without spoiling the iconic view. Other reasons for choosing a tunnel instead of a bridge include avoiding difficulties with tides, weather, and shipping during construction (as in the 51.5-kilometre or 32.0-mile Channel Tunnel ), aesthetic reasons (preserving the above-ground view, landscape, and scenery), and also for weight capacity reasons (it may be more feasible to build

9310-564: Was diverted into the Ted Williams Tunnel , Tobin Bridge , and Massachusetts Route 1A South via Revere or East Boston. Starting with the Accelerated Bridge Program in the late 2000s, MassDOT began employing accelerated construction techniques, in which it signed contracts with incentives for early completion and penalties for late completion, and used intense construction during longer periods of complete closure to shorten

9408-440: Was opened in 1961. It was named for the son of Turnpike chairman William F. Callahan , who was killed in Italy days before the end of World War II. Formerly, control signals were used to reverse the direction of one lane in this tunnel or the Sumner Tunnel, when the opposite tunnel was closed for maintenance or emergencies. Under the relevant Turnpike regulations, a yellow signal light means "proceed only as directed", on penalty of

9506-732: Was superseded by the Madrid M30 ringroad , Spain, and the Chong Ming tunnels in Shanghai , China. All of these machines were built at least partly by Herrenknecht . As of August 2013 , the world's largest TBM was " Big Bertha ", a 17.5-metre (57.5 ft) diameter machine built by Hitachi Zosen Corporation , which dug the Alaskan Way Viaduct replacement tunnel in Seattle, Washington (US). A temporary access shaft

9604-987: Was the largest water supply scheme of its time. Examples of significant water pipelines in South Australia are the Morgan-Whyalla pipeline (completed 1944) and Mannum-Adelaide pipeline (completed 1955) pipelines, both part of the larger Snowy Mountains scheme . There are two Los Angeles, California aqueducts, the Owens Valley aqueduct (completed 1913) and the Second Los Angeles Aqueduct (completed 1970) which also include extensive use of pipelines. The Great Manmade River of Libya supplies 3,680,000 cubic metres (4,810,000 cu yd) of water each day to Tripoli, Benghazi, Sirte, and several other cities in Libya. The pipeline

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