Misplaced Pages

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129-726: Interstate 80 ( I-80 ) is a transcontinental Interstate Highway in the United States, stretching from San Francisco, California , to Teaneck, New Jersey . The segment of I-80 in California runs east from San Francisco across the San Francisco–Oakland Bay Bridge to Oakland , where it turns north and crosses the Carquinez Bridge before turning back northeast through the Sacramento Valley . I-80 then traverses

258-522: A concurrency or overlap. For example, I‑75 and I‑85 share the same roadway in Atlanta ; this 7.4-mile (11.9 km) section, called the Downtown Connector , is labeled both I‑75 and I‑85. Concurrencies between Interstate and US Highway numbers are also allowed in accordance with AASHTO policy, as long as the length of the concurrency is reasonable. In rare instances, two highway designations sharing

387-637: A 28-year-old brevet lieutenant colonel, accompanied the trip "through darkest America with truck and tank," as he later described it. Some roads in the West were a "succession of dust, ruts, pits, and holes." As the landmark 1916 law expired, new legislation was passed—the Federal Aid Highway Act of 1921 (Phipps Act). This new road construction initiative once again provided for federal matching funds for road construction and improvement, $ 75 million allocated annually. Moreover, this new legislation for

516-476: A change in the numbering system as a result of a new policy adopted in 1973. Previously, letter-suffixed numbers were used for long spurs off primary routes; for example, western I‑84 was I‑80N, as it went north from I‑80 . The new policy stated, "No new divided numbers (such as I-35W and I-35E , etc.) shall be adopted." The new policy also recommended that existing divided numbers be eliminated as quickly as possible; however, an I-35W and I-35E still exist in

645-580: A national road grid with the passage of the Federal Aid Highway Act of 1921 . In 1926, the United States Numbered Highway System was established, creating the first national road numbering system for cross-country travel. The roads were state-funded and maintained, and there were few national standards for road design. United States Numbered Highways ranged from two-lane country roads to multi-lane freeways. After Dwight D. Eisenhower became president in 1953, his administration developed

774-626: A new earthquake-resisting technique that would not collapse in an earthquake similar to the Loma Prieta earthquake. The new eastern span opened on September 2, 2013, at an estimated cost of $ 6.4 billion (equivalent to $ 8.26 billion in 2023). In May 2022, Caltrans began construction on 18-mile (29 km) high-occupancy toll (HOT) lanes along I-80 between Red Top Road in Fairfield and Leisure Town Road in Vacaville . The project includes converting

903-490: A new freeway through San Francisco . According to the article, the suggested 19th Avenue tunnel would run five miles (8.0 km), from Junipero Serra Boulevard through Golden Gate Park and up to Lake Street, with exits at Brotherhood Avenue, Ocean Avenue, Quintara Street, Lincoln Way , and Geary Boulevard . The Van Ness tunnel would run almost two miles (3.2 km), from about Fell Street to Lombard Street , with exits at Broadway and Geary Boulevard. Along Oak and Fell,

1032-576: A numbering scheme in which primary Interstates are assigned one- or two-digit numbers, and shorter routes which branch off of longer ones are assigned three-digit numbers where the last two digits match the parent route. The Interstate Highway System is partially financed through the Highway Trust Fund , which itself is funded by a combination of a federal fuel tax and transfers from the Treasury's general fund. Though federal legislation initially banned

1161-481: A proposal for an interstate highway system, eventually resulting in the enactment of the Federal-Aid Highway Act of 1956 . Unlike the earlier United States Numbered Highway System, the interstates were designed to be all freeways, with nationally unified standards for construction and signage. While some older freeways were adopted into the system, most of the routes were completely new. In dense urban areas,

1290-540: A report called Toll Roads and Free Roads , "the first formal description of what became the Interstate Highway System" and, in 1944, the similarly themed Interregional Highways . The Interstate Highway System gained a champion in President Dwight D. Eisenhower, who was influenced by his experiences as a young Army officer crossing the country in the 1919 Motor Transport Corps convoy that drove in part on

1419-578: A section of a continuous Highway 403, the new link was designated as a western extension of the tolled Highway 407, with the Mississauga section of Highway 403 planned to be renumbered as Highway 410. The renumbering to 410 never came to pass, and consequently Highway 403 was signed concurrently along the Queen Elizabeth Way in 2002, remedying the discontinuity. Nonetheless, many surface street signs referring to that section of freeway with

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1548-409: A single digit prefixed to the two-digit number of its parent Interstate Highway. Spur routes deviate from their parent and do not return; these are given an odd first digit. Circumferential and radial loop routes return to the parent, and are given an even first digit. Unlike primary Interstates, three-digit Interstates are signed as either east–west or north–south, depending on the general orientation of

1677-433: A single mountain crossing or over a bridge, or through a major city, it is often economically and practically advantageous for them all to be accommodated on a single physical roadway. In some jurisdictions, however, concurrent numbering is avoided by posting only one route number on highway signs; other route numbers disappear at the start of the concurrency and reappear when it ends. However, any route that becomes unsigned in

1806-423: A single numbered route across each province (an exception being the switching of the designation between Nova Scotia Highways 104 and 105 ), or has branches that are signed exclusively as TCH routes. In Ontario and Quebec, The TCH follows a series of provincial highways, and also has branches that follow sections of others that have concurrencies with it, signed with TCH shields alongside the provincial number. In

1935-769: A speed limit of 45 mph (70 km/h) because it is a parkway that consists of only one lane per side of the highway. On the other hand, Interstates 15, 80, 84, and 215 in Utah have speed limits as high as 70 mph (115 km/h) within the Wasatch Front , Cedar City , and St. George areas, and I-25 in New Mexico within the Santa Fe and Las Vegas areas along with I-20 in Texas along Odessa and Midland and I-29 in North Dakota along

2064-456: A speed limit of 80 mph (130 km/h). Other Interstates in Idaho, Montana, Oklahoma, South Dakota and Wyoming also have the same high speed limits. In some areas, speed limits on Interstates can be significantly lower in areas where they traverse significantly hazardous areas. The maximum speed limit on I-90 is 50 mph (80 km/h) in downtown Cleveland because of two sharp curves with

2193-467: A suggested limit of 35 mph (55 km/h) in a heavily congested area; I-70 through Wheeling, West Virginia , has a maximum speed limit of 45 mph (70 km/h) through the Wheeling Tunnel and most of downtown Wheeling; and I-68 has a maximum speed limit of 40 mph (65 km/h) through Cumberland, Maryland , because of multiple hazards including sharp curves and narrow lanes through

2322-536: A variety of concurrences which can occur. An example of this is the concurrency of Interstate 70 (I-70) and I-76 on the Pennsylvania Turnpike in western Pennsylvania . I-70 merges with the Pennsylvania Turnpike so the route number can ultimately continue east into Maryland; instead of having a second physical highway built to carry the route, it is combined with the Pennsylvania Turnpike and

2451-607: Is SR 51 ). SR 244 heads east as a short freeway spur from that interchange. Crossing the Sierra Nevada , I-80 regularly gets snow at higher elevations from fall to spring. The California Department of Transportation (Caltrans) sometimes requires vehicles to use snow tires , snow chains , or other traction devices in the mountains during and after snowstorms . Checkpoints are often set up to enforce chain restrictions on vehicles bound for icy or snowy areas. When chain restrictions are in effect, vehicles must have chains on

2580-534: Is a wrong-way concurrency where the northbound direction is signed as I-80 east and I-580 west, while the southbound direction is signed as westbound I-80 and eastbound I-580. This segment suffers from severe traffic congestion during rush hour due to the merger of three freeways (I-80, I-580, and I-880 ) at the MacArthur Maze. The Eastshore Freeway was created in the mid-1950s (construction commenced in 1954, last segment completed May 10, 1960) by reengineering

2709-607: Is a segment of I-80 and I-580 along the northeast shoreline of San Francisco Bay . It runs from the MacArthur Maze interchange just east of the eastern end of the San Francisco–Oakland Bay Bridge to the Carquinez Bridge . I-580 splits from the Eastshore Freeway at an interchange known locally as the "Hoffman Split" in Albany . The section of the Eastshore Freeway between the MacArthur Maze and I-580 (Hoffman) split between Albany

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2838-534: Is also commonly believed the Interstate Highway System was built for the sole purpose of evacuating cities in the event of nuclear warfare . While military motivations were present, the primary motivations were civilian. The numbering scheme for the Interstate Highway System was developed in 1957 by the American Association of State Highway and Transportation Officials (AASHTO). The association's present numbering policy dates back to August 10, 1973. Within

2967-465: Is in downtown Athens, Georgia , between exits 4 and 8 of SR 10 Loop , where the highway is concurrent with US 29 , US 78 , US 129 , US 441 , SR 8 , SR 15 , and SR 422. In the United States, concurrencies are simply marked by placing signs for both routes on the same or adjacent posts. The federal Manual on Uniform Traffic Control Devices prescribes that when mounting these adjacent signs together that

3096-468: Is located in Nevada County, California . The pass is generally open year-round; it is plowed in winter but may temporarily close during the worst snowstorms. The older, original US 40/Lincoln Highway route over Donner Pass is about two miles (3.2 km) to the south. This highway was replaced as the official trans-Sierra route by I-80 in 1964. Although the current Donner Pass is lower, Euer Saddle

3225-486: Is now used for three railroad stations. In 1980, the new I-80 alignment was deleted from the Interstate System. SR 244 was then truncated from its proposed alignment to the only freeway section of the abandoned project in 1994, which is about a mile (1.6 km) long. In 1982–1984, I-880 was reassigned to SR 17 running from Oakland to San Jose , after two to four years of inactivity. On October 17, 1989,

3354-554: Is officially designated " Daniel Interchange ", providing half of the possible interchange directions. It is a one-mile (1.6 km) segment consisting of eight lanes providing high-speed access between the two highways. Access from Highway 1 west to Highway 6 south and Highway 6 north to Highway 1 east is provided via Route 431 , while access between Highway 1 east to Highway 6 north and Highway 6 south to Highway 1 west are provided at Ben Shemen Interchange. The other movements are provided through

3483-669: Is part of the California Freeway and Expressway System and is part of the National Highway System , a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration (FHWA). I-80 is also known as the Dutch Flat and Donner Lake Wagon Road from Emigrant Gap to Donner Lake. The segment of I-80 from Emigrant Gap to Truckee also forms part of

3612-595: Is signed) and Interstate 81 (which runs primarily northeast–southwest, but is also signed north–south). A vehicle might simultaneously be on I-77 northbound and I-81 southbound, while actually traveling due westbound. An unusual example of a three-directional concurrency occurs southeast of Rhinelander, Wisconsin , where US 8 westbound (the actual compass direction) converges with southbound Wisconsin Highway 17 and northbound Wisconsin Highway 47 , and vice-versa. Often when two routes with exit numbers overlap, one of

3741-525: Is to have the highway route extend from Tamaulipas , Mexico to Ontario , Canada. The planned I-11 will then bridge the Interstate gap between Phoenix, Arizona and Las Vegas, Nevada , and thus form part of the CANAMEX Corridor (along with I-19 , and portions of I-10 and I-15 ) between Sonora , Mexico and Alberta , Canada. Political opposition from residents canceled many freeway projects around

3870-401: Is today named "Eastshore Boulevard". Originally, the name "Eastshore Freeway" was also applied to what is today known as the " Nimitz Freeway " (I-880) from the beginning of its construction in 1947. This freeway was dedicated in 1958 to Chester W. Nimitz , and so, for a few years in the 1950s prior, the Eastshore Freeway stretched the entire length of the east shore of San Francisco Bay. Until

3999-623: The 1964 state highway renumbering . US 40 was one of the original California routes designed in 1926, although its west end was in Oakland with US 101E (then SR 17 , then I-5W , now I-580 / I-880 ) prior to the San Francisco–Oakland Bay Bridge opening in 1936. An auto ferry ran from Berkeley to San Francisco, signed at the ferry landings for US 40. After the San Francisco–Oakland Bay Bridge's construction, US 40, along with US 50 , were extended along

Interstate 80 in California - Misplaced Pages Continue

4128-551: The American Association of State Highway and Transportation Officials (AASHTO) rejected the numbering. The state law authorizing the renumbering was passed on September 20, 1963. Signage changes took place by July 1, 1964, and US 40 was decommissioned. US 40 was one of the first US Routes to be decommissioned completely in California. In the Sacramento area, I-80 has been realigned to many routes. In 1964, I-80 used

4257-508: The American Association of State Highway and Transportation Officials for permission to truncate US 27 at Fort Wayne, Indiana . In 2002, Michigan removed the US ;27 designation from I-69 and extended the US ;127 designation from Lansing to Grayling. MDOT's stated reason for the modification was to "reduce confusion along the US 27/US 127 corridor". After US 27's signage

4386-519: The Beckwourth Pass , at an elevation of 5,221 feet (1,591 m). Driving across the Sierra Nevada became far easier with the construction of I-80 across Donner Summit since that pass is closed only for intense snowstorms. In 1964, Caltrans desired to reduce the number of designated routes in the California state highways system. The Interstate Highway System , designed and built starting in 1956,

4515-474: The Dallas–Fort Worth metroplex in Texas, and an I-35W and I-35E that run through Minneapolis and Saint Paul , Minnesota, still exist. Additionally, due to Congressional requirements, three sections of I-69 in southern Texas will be divided into I-69W , I-69E , and I-69C (for Central). AASHTO policy allows dual numbering to provide continuity between major control points. This is referred to as

4644-538: The Federal Aid Highway Act of 1956 into law. Under the act, the federal government would pay for 90 percent of the cost of construction of Interstate Highways. Each Interstate Highway was required to be a freeway with at least four lanes and no at-grade crossings. The publication in 1955 of the General Location of National System of Interstate Highways , informally known as the Yellow Book , mapped out what became

4773-538: The Grand Forks area have higher speed limits of 75 mph (120 km/h). As one of the components of the National Highway System , Interstate Highways improve the mobility of military troops to and from airports, seaports, rail terminals, and other military bases. Interstate Highways also connect to other roads that are a part of the Strategic Highway Network , a system of roads identified as critical to

4902-827: The Interstate Highway System , or the Eisenhower Interstate System , is a network of controlled-access highways that forms part of the National Highway System in the United States . The system extends throughout the contiguous United States and has routes in Hawaii , Alaska , and Puerto Rico . In the 20th century, the United States Congress began funding roadways through the Federal Aid Road Act of 1916 , and started an effort to construct

5031-515: The Lincoln Highway , the first road across America. He recalled that, "The old convoy had started me thinking about good two-lane highways... the wisdom of broader ribbons across our land." Eisenhower also gained an appreciation of the Reichsautobahn system, the first "national" implementation of modern Germany's Autobahn network, as a necessary component of a national defense system while he

5160-515: The Loma Prieta earthquake was responsible for 63 deaths and 3,757 injuries. The San Francisco–Oakland Bay Bridge , which is part of I-80, suffered severe damage, as a 76-by-50-foot (23 m × 15 m) section of the upper deck on the eastern cantilever side fell onto the deck below. The quake caused the Oakland side of the bridge to shift seven inches (18 cm) to the east and caused

5289-584: The Oklahoma – Arkansas state line. At the northern end of this border Oklahoma State Highway 20 runs concurrently with Arkansas Highway 43 and the two highways run north–south along the boundary. Concurrencies are also found in Canada. British Columbia Highway 5 continues east for 12 kilometres (7.5 mi) concurrently with Highway 1 and Highway 97 , through Kamloops . This stretch of road, which carries Highway 97 south and Highway 5 north on

Interstate 80 in California - Misplaced Pages Continue

5418-752: The Sacramento area. Currently, the freeway runs on a northern bypass of the city, the Beltline Freeway, that was originally designated I-880. The I-80 routing alignment was moved from a route through Sacramento, now US 50 and I-80 Business (I-80 Bus), after the proposed I-80 replacement of the North Sacramento Freeway was canceled. The Beltline Freeway runs northeast from the junction of I-80 and US 50 in West Sacramento across I-5 to its junction northeast of Sacramento with I-80 Bus (which

5547-633: The San Francisco Bay Area : In addition, I-238 may be considered associated with I-80 even though it does not follow established rules for numbering Interstates as there is no I-38. As it connects I-580 in Castro Valley with I-880 in San Leandro , it would normally also use a three-digit number ending in 80. But, of the nine possible numbers, two ( 180 and 480 ) were in use by State Routes (the latter an Interstate until 1968 though SR 480

5676-509: The Sierra Nevada , cresting at Donner Summit , before crossing into the state of Nevada within the Truckee River Canyon. The speed limit is at most 65 mph (105 km/h) along the entire route instead of the state's maximum of 70 mph (110 km/h) as most of the route is in either urban areas or mountainous terrain. I-80 has portions designated as the Eastshore Freeway and Alan S. Hart Freeway. Throughout California, I-80

5805-499: The US Department of Defense . The system has also been used to facilitate evacuations in the face of hurricanes and other natural disasters. An option for maximizing traffic throughput on a highway is to reverse the flow of traffic on one side of a divider so that all lanes become outbound lanes. This procedure, known as contraflow lane reversal , has been employed several times for hurricane evacuations. After public outcry regarding

5934-464: The US Highways , which increase from east to west and north to south). This numbering system usually holds true even if the local direction of the route does not match the compass directions. Numbers divisible by five are intended to be major arteries among the primary routes, carrying traffic long distances. Primary north–south Interstates increase in number from I-5 between Canada and Mexico along

6063-541: The West Coast to I‑95 between Canada and Miami, Florida along the East Coast . Major west–east arterial Interstates increase in number from I-10 between Santa Monica, California , and Jacksonville, Florida , to I-90 between Seattle, Washington , and Boston, Massachusetts , with two exceptions. There are no I-50 and I-60, as routes with those numbers would likely pass through states that currently have US Highways with

6192-652: The Yuba–Donner Scenic Byway , a National Forest Scenic Byway . According to the California Streets and Highways Code, most maps, and local signs, I-80 begins at the interchange with US 101 in San Francisco. However, federal records place the western terminus of I-80 at the western approach to the San Francisco–Oakland Bay Bridge , at the location of the Fremont Street offramp (previously known as

6321-450: The concurrency of I-75 and I-85 in Atlanta, Georgia —where I-75 is dominant—the exit numbers range from 242 to 251, while I-85's highest independent mile marker in Georgia is 179. Some brief concurrencies in the past have been eliminated by reassigning the designations along the roadways. This can involve scaling back the terminus of one designation to the end of a concurrent section. At

6450-559: The Congress Hotel in Chicago. In the plan, Mehren proposed a 50,000-mile (80,000 km) system, consisting of five east–west routes and 10 north–south routes. The system would include two percent of all roads and would pass through every state at a cost of $ 25,000 per mile ($ 16,000/km), providing commercial as well as military transport benefits. In 1919, the US Army sent an expedition across

6579-570: The Czech Republic, the European route numbers are only additional, and they are always concurrent with the state route numbering, usually highways or first-class roads. In the state numbering system, concurrences exist only in first-class and second-class roads; third class roads do not have them. The local term for such concurrences is peáž (from the French word péage ). In the road register, one of

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6708-578: The Eastshore Highway, a thoroughfare constructed in the 1930s (1934–1937) as one of the approaches to the Bay Bridge and designated as part of US 40 . The Eastshore Highway began in El Cerrito at an intersection with San Pablo Avenue at Hill Street between Potrero Avenue and Cutting Boulevard, adjacent to the location today of the El Cerrito del Norte station of Bay Area Rapid Transit (BART). It

6837-603: The I-76 designation. The longest Interstate Highway concurrency is I-80 and I-90 for 278 miles (447 km) across Indiana and Ohio . There are at least two examples of eight-way concurrencies. The first example is in Indianapolis, between exits 46 and 47 of the 53-mile (85 km) I-465 beltway , where the highway is concurrent with I-69 , U.S. Highway 31 (US 31), US 36 , US 40 , US 52 , US 421 , and State Road 67 . The second example

6966-506: The Interstate Highway System. Assisting in the planning was Charles Erwin Wilson , who was still head of General Motors when President Eisenhower selected him as Secretary of Defense in January 1953. Some sections of highways that became part of the Interstate Highway System actually began construction earlier. Three states have claimed the title of first Interstate Highway. Missouri claims that

7095-424: The Interstate Highway program. The Interstates of Alaska and Puerto Rico are numbered sequentially in order of funding without regard to the rules on odd and even numbers. They also carry the prefixes A and PR , respectively. However, these highways are signed according to their local designations, not their Interstate Highway numbers. Furthermore, these routes were neither planned according to nor constructed to

7224-557: The Panhandle Freeway project. A January 1968 amendment moved I-280 to its present alignment, degraded I-480 to a state highway, and truncated the origin point of I-80 to the Embarcadero Freeway (then I-280, formerly I-480). Prior to that truncation, I-80 had been defined as from "Route 280 in San Francisco to the Nevada state line near Verdi, Nevada, passing near Division Street in San Francisco, passing near Oakland, via Albany, via Sacramento, passing near North Sacramento, passing near Roseville, via Auburn, via Emigrant Gap, via Truckee and via

7353-403: The QEW/Highway 403 concurrency still only use the highway's original designation of QEW, although the MTO has updated route markers on the QEW to reflect the concurrency. At the national level, the Trans-Canada Highway , which does not bear a uniform number in the eastern provinces, follows various provincial highways. In the Atlantic Provinces the main designated TCH route either follows

7482-402: The SR 241 designation has since been reassigned to an unrelated stretch of highway in Orange County .) The San Francisco Skyway, which had already been signed as part of I-80, has remained a de facto section of I-80 to the present day and remains listed as part of the Interstate in California. In 2000, the San Francisco Chronicle published an article about the proposed construction of

7611-500: The Sierra Nevada north of historic US 40. When I-80 was first approved, it was to begin at planned I-280 ( SR 1 ) in Golden Gate Park , head east on the never-built Panhandle Freeway , then run south and southeast on the Central Freeway (US 101) to the San Francisco Skyway. The Panhandle Freeway was to be routed through Hayes Valley , passing through Golden Gate Park and terminating at proposed I-280, now SR 1. In 1964, community oppositions forced Caltrans to abandon

7740-399: The Terminal Separator Structure that once connected it to the Embarcadero Freeway ). The federal and state governments disagree as to whether this westernmost segment of the signed Interstate, known as the San Francisco Skyway or Bayshore Viaduct, is actually part of the Interstate Highway System , although it is consistently shown as I-80 on most maps of San Francisco. The Eastshore Freeway

7869-409: The Truckee River Canyon", and certain maps had been shown of I-80 running concurrently with US 101 to Fell Street. These changes were made on the state level later that year, but Route 80 was only truncated to US 101. (The Central Freeway remained part of US 101, and the Panhandle Freeway became SR 241. The Panhandle Freeway was later canceled in the wake of freeway revolts , and

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7998-644: The UK, the existence of these concurrencies is purely theoretical. In Sweden and Denmark, the most important highways use only the European route numbers that have cardinal directions. In Sweden the European route E6 and E20 run concurrently for 280 kilometres (170 mi). In Denmark the E47 and E55 run concurrently for 157 kilometres (98 mi). There are more shorter concurrencies. There are two stretches in Sweden and Denmark where three European routes run concurrently; these are E6, E20 and E22 in Sweden, and E20, E47, and E55 in Denmark. Along all these concurrencies, all route numbers are posted with signs. In

8127-506: The US to determine the difficulties that military vehicles would have on a cross-country trip. Leaving from the Ellipse near the White House on July 7, the Motor Transport Corps convoy needed 62 days to drive 3,200 miles (5,100 km) on the Lincoln Highway to the Presidio of San Francisco along the Golden Gate . The convoy suffered many setbacks and problems on the route, such as poor-quality bridges, broken crankshafts, and engines clogged with desert sand. Dwight Eisenhower , then

8256-412: The United Kingdom, routes do not run concurrently with others. Where this would normally occur, the roadway takes the number of only one of the routes (usually, but not always, the most important route), while the other routes are considered to have a gap and are signed in brackets (the equivalent of "to" signs in North America). An example is the meeting of the M60 and the M62 northwest of Manchester :

8385-631: The United States, including: In addition to cancellations, removals of freeways are planned: The American Association of State Highway and Transportation Officials (AASHTO) has defined a set of standards that all new Interstates must meet unless a waiver from the Federal Highway Administration (FHWA) is obtained. One almost absolute standard is the controlled access nature of the roads. With few exceptions , traffic lights (and cross traffic in general) are limited to toll booths and ramp meters (metered flow control for lane merging during rush hour ). Being freeways , Interstate Highways usually have

8514-413: The act was signed, and paving started September 26, 1956. The state marked its portion of I-70 as the first project in the United States completed under the provisions of the new Federal-Aid Highway Act of 1956. The Pennsylvania Turnpike could also be considered one of the first Interstate Highways, and is nicknamed "Grandfather of the Interstate System". On October 1, 1940, 162 miles (261 km) of

8643-425: The bolts of one section to shear off, sending the 250-short-ton (230 t; 220-long-ton) section of roadbed crashing down like a trapdoor. Caltrans removed and replaced the collapsed section and reopened the bridge on November 18. In 2002, due to the risk of a future large earthquake, Caltrans started building a new eastern span. The department advertised that the new span of the San Francisco–Oakland Bay Bridge used

8772-614: The bridge to connect with US 101 . The auto ferry service was then discontinued. US 40 and US 50 both followed the San Francisco–Oakland Bay Bridge and the routes split on what is the present day MacArthur Maze in Oakland. US 50 continued southeast on present-day I-580 to Stockton and US 40 closely followed the route of present-day I-80. When reaching Sacramento , US 40 and US 50 rejoined, US 50 running concurrently with former US 99 from Stockton to Sacramento. US 40 then again split with US 50 in Downtown Sacramento and closely followed

8901-399: The cancellation of the Somerset Freeway . This situation was remedied when the construction of the Pennsylvania Turnpike/Interstate 95 Interchange Project started in 2010 and partially opened on September 22, 2018, which was already enough to fill the gap. However, I-70 remains discontinuous in Pennsylvania , because of the lack of a direct interchange with the Pennsylvania Turnpike at

9030-406: The choice of routing destroyed many well-established neighborhoods, often intentionally as part of a program of " urban renewal ". In the two decades following the 1956 Highway Act, the construction of the freeways displaced one million people, and as a result of the many freeway revolts during this era, several planned Interstates were abandoned or re-routed to avoid urban cores. Construction of

9159-538: The city. In some locations, low speed limits are the result of lawsuits and resident demands; after holding up the completion of I-35E in St. Paul, Minnesota , for nearly 30 years in the courts, residents along the stretch of the freeway from the southern city limit to downtown successfully lobbied for a 45 mph (70 km/h) speed limit in addition to a prohibition on any vehicle weighing more than 9,000 pounds (4,100 kg) gross vehicle weight . I-93 in Franconia Notch State Park in northern New Hampshire has

9288-401: The collection of tolls, some Interstate routes are toll roads , either because they were grandfathered into the system or because subsequent legislation has allowed for tolling of Interstates in some cases. As of 2022 , about one quarter of all vehicle miles driven in the country used the Interstate Highway System, which has a total length of 48,890 miles (78,680 km). In 2022 and 2023,

9417-455: The concurrency. Since highways in the United States and Canada are usually signed with assigned cardinal directions based on their primary orientation, it is possible for a stretch of roadway shared between two highways to be signed with conflicting, even opposite, cardinal directions in a wrong-way concurrency . For example, near Wytheville, Virginia , there is a concurrency between Interstate 77 (which runs primarily north–south, as it

9546-497: The construction and improvement of highways. The nation's revenue needs associated with World War I prevented any significant implementation of this policy, which expired in 1921. In December 1918, E. J. Mehren, a civil engineer and the editor of Engineering News-Record , presented his "A Suggested National Highway Policy and Plan" during a gathering of the State Highway Officials and Highway Industries Association at

9675-407: The contiguous United States, primary Interstates—also called main line Interstates or two-digit Interstates—are assigned numbers less than 100. While numerous exceptions do exist, there is a general scheme for numbering Interstates. Primary Interstates are assigned one- or two-digit numbers, while shorter routes (such as spurs, loops, and short connecting roads) are assigned three-digit numbers where

9804-637: The creation of an artificial lagoon which was developed by the Works Progress Administration (WPA) in the late 1930s as Aquatic Park . The frontage road along the east side of today's Eastshore Freeway between Buchanan Street in Albany and Hearst Avenue in Berkeley retains the name "Eastshore Highway". The terminal segment of the old Eastshore Highway in El Cerrito between Potrero and San Pablo avenues

9933-618: The discontinuity, but they have been blocked by local opposition, fearing a loss of business. The Interstate Highway System has been expanded numerous times. The expansions have both created new designations and extended existing designations. For example, I-49 , added to the system in the 1980s as a freeway in Louisiana , was designated as an expansion corridor, and FHWA approved the expanded route north from Lafayette, Louisiana , to Kansas City, Missouri . The freeway exists today as separate completed segments, with segments under construction or in

10062-448: The dissemination of public information. As a result, the 2005 evacuation of New Orleans, Louisiana, prior to Hurricane Katrina ran much more smoothly. According to urban legend , early regulations required that one out of every five miles of the Interstate Highway System must be built straight and flat, so as to be usable by aircraft during times of war. There is no evidence of this rule being included in any Interstate legislation. It

10191-417: The driving wheels, except 4WD vehicles with snow tires. Additionally, during the winter season, trucks are required to carry chains whether or not controls are in force. I-80 crosses the Sierra Nevada crest at Donner Summit (also known as Euer Saddle) at an elevation of 7,239 feet (2,206 m) westbound and 7,227 feet (2,203 m) eastbound. The Donner Summit Rest Area is located at this point. The summit

10320-492: The eastern end of the concurrency near Breezewood . Traveling in either direction, I-70 traffic must exit the freeway and use a short stretch of US 30 (which includes a number of roadside services) to rejoin I-70. The interchange was not originally built because of a legacy federal funding rule, since relaxed, which restricted the use of federal funds to improve roads financed with tolls. Solutions have been proposed to eliminate

10449-450: The economy. Not just as a public works measure, but for future growth. Clay's committee proposed a 10-year, $ 100 billion program ($ 1.13 trillion in 2023), which would build 40,000 miles (64,000 km) of divided highways linking all American cities with a population of greater than 50,000. Eisenhower initially preferred a system consisting of toll roads , but Clay convinced Eisenhower that toll roads were not feasible outside of

10578-656: The existing 8-mile (13 km) carpool lanes between Red Top Road and Air Base Parkway. Scheduled to open in 2025, the HOT lanes will use an open road tolling system, and therefore no toll booths to receive cash, with each vehicle required to carry a FasTrak transponder. In May 2024, the California Transportation Commission approved $ 105 million for a project that would add HOT lanes between Davis and West Sacramento . The following auxiliary Interstate Highways are associated with I-80 in California, all in

10707-488: The existing, largely non-freeway, United States Numbered Highways system. By the late 1930s, planning had expanded to a system of new superhighways. In 1938, President Franklin D. Roosevelt gave Thomas MacDonald , chief at the Bureau of Public Roads, a hand-drawn map of the United States marked with eight superhighway corridors for study. In 1939, Bureau of Public Roads Division of Information chief Herbert S. Fairbank wrote

10836-426: The federal government, Interstate Highways are owned by the state in which they were built. With few exceptions , all Interstates must meet specific standards , such as having controlled access, physical barriers or median strips between lanes of oncoming traffic, breakdown lanes , avoiding at-grade intersections , no traffic lights , and complying with federal traffic sign specifications. Interstate Highways use

10965-507: The first three contracts under the new program were signed in Missouri on August 2, 1956. The first contract signed was for upgrading a section of US Route 66 to what is now designated Interstate 44 . On August 13, 1956, work began on US 40 (now I-70) in St. Charles County. Kansas claims that it was the first to start paving after the act was signed. Preliminary construction had taken place before

11094-594: The first time sought to target these funds to the construction of a national road grid of interconnected "primary highways", setting up cooperation among the various state highway planning boards. The Bureau of Public Roads asked the Army to provide a list of roads that it considered necessary for national defense. In 1922, General John J. Pershing , former head of the American Expeditionary Force in Europe during

11223-572: The freeway was rerouted around the city after plans to upgrade the original grandfathered route through the city to Interstate Highway standards were canceled. I-80 is recognized as the Dwight D. Eisenhower Highway in the Western United States and a Blue Star Memorial Highway for its entire length. In California, it follows the original corridor of the Lincoln Highway from Sacramento to Reno (with minor deviations near Donner Summit ). I-80

11352-542: The highest speed limits in a given area. Speed limits are determined by individual states. From 1975 to 1986, the maximum speed limit on any highway in the United States was 55 miles per hour (90 km/h), in accordance with federal law. Typically, lower limits are established in Northeastern and coastal states, while higher speed limits are established in inland states west of the Mississippi River . For example,

11481-542: The highly populated coastal regions. In February 1955, Eisenhower forwarded Clay's proposal to Congress. The bill quickly won approval in the Senate, but House Democrats objected to the use of public bonds as the means to finance construction. Eisenhower and the House Democrats agreed to instead finance the system through the Highway Trust Fund , which itself would be funded by a gasoline tax. In June 1956, Eisenhower signed

11610-607: The highway now designated I‑70 and I‑76 opened between Irwin and Carlisle . The Commonwealth of Pennsylvania refers to the turnpike as the Granddaddy of the Pikes, a reference to turnpikes . Milestones in the construction of the Interstate Highway System include: The initial cost estimate for the system was $ 25 billion over 12 years; it ended up costing $ 114 billion (equivalent to $ 425 billion in 2006 or $ 618 billion in 2023 ) and took 35 years. The system

11739-454: The inefficiency of evacuating from southern Louisiana prior to Hurricane Georges ' landfall in September 1998, government officials looked towards contraflow to improve evacuation times. In Savannah, Georgia , and Charleston, South Carolina , in 1999, lanes of I-16 and I-26 were used in a contraflow configuration in anticipation of Hurricane Floyd with mixed results. In 2004, contraflow

11868-431: The last two digits match the parent route (thus, I-294 is a loop that connects at both ends to I-94 , while I-787 is a short spur route attached to I-87 ). In the numbering scheme for the primary routes, east–west highways are assigned even numbers and north–south highways are assigned odd numbers. Odd route numbers increase from west to east, and even-numbered routes increase from south to north (to avoid confusion with

11997-536: The late 1960s, the Eastshore Freeway was also designated as part of State Route 17 (SR 17) together with the Nimitz Freeway. This section of I-80 has a top speed of 65 mph (105 km/h), unlike California's top speed limit of 70 mph (110 km/h), common in rural freeways. I-80 is a six- to eight-lane freeway with carpool lanes in Fairfield between exit 39A (Red Top Road) and exit 47 (Air Base Parkway). I-80 has changed routing in

12126-450: The mainline. Some auxiliary highways do not follow these guidelines, however. The Interstate Highway System also extends to Alaska , Hawaii , and Puerto Rico , even though they have no direct land connections to any other states or territories. However, their residents still pay federal fuel and tire taxes. The Interstates in Hawaii, all located on the most populous island of Oahu , carry

12255-503: The many traffic signals , yield signs , and stop signs that seemed to appear out of nowhere. Caltrans listed five intersections with high accident rates and claimed construction of I-80 would reduce such accidents. According to a study done on I-80 in Vallejo from 1955 and 1956, prior to the freeway construction, and 1957 and 1958, after the freeway was constructed, the accident rate dropped 73 percent and there were 245 fewer accidents on

12384-737: The maximum speed limit is 75 mph (120 km/h) in northern Maine, varies between 50 and 70 mph (80 and 115 km/h) from southern Maine to New Jersey, and is 50 mph (80 km/h) in New York City and the District of Columbia. Currently, rural speed limits elsewhere generally range from 65 to 80 miles per hour (105 to 130 km/h). Several portions of various highways such as I-10 and I-20 in rural western Texas, I-80 in Nevada between Fernley and Winnemucca (except around Lovelock) and portions of I-15 , I-70 , I-80 , and I-84 in Utah have

12513-579: The middle of the concurrency will still be signed on most maps and road atlases. Most concurrencies are simply a combination of at least two route numbers on the same physical roadway. This is often practically advantageous as well as economically advantageous; it may be better for two route numbers to be combined into one along rivers or through mountain valleys. Some countries allow for concurrencies to occur, however, others specifically do not allow it to happen. In those nations which do permit concurrencies, it can become very common. In these countries, there are

12642-558: The motorways coincide for the seven miles (11 km) between junctions 12 and 18 but the motorway between those points is only designated as the M60 (although in this case the same junction numbers would also apply to the M62). European route numbers as designated by UNECE may have concurrencies (for instance E15 and E30 around Greater London ), but since the E-route numbers are unsigned and unused in

12771-404: The number of fatalities on the Interstate Highway System amounted to more than 5,000 people annually, with nearly 5,600 fatalities in 2022. The United States government's efforts to construct a national network of highways began on an ad hoc basis with the passage of the Federal Aid Road Act of 1916 , which provided $ 75 million over a five-year period for matching funds to the states for

12900-469: The numbers will be arranged vertically or horizontally in order of precedence. The order to be used is Interstate Highways , U.S. Highways , state highways , and finally county roads , and within each class by increasing numerical value. Several states do not officially have any concurrencies, instead officially ending routes on each side of one. There are several circumstances where unusual concurrencies exist along state borders. One example occurs along

13029-526: The official Interstate Highway standards . On one- or two-digit Interstates, the mile marker numbering almost always begins at the southern or western state line. If an Interstate originates within a state, the numbering begins from the location where the road begins in the south or west. As with all guidelines for Interstate routes, however, numerous exceptions exist. Wrong-way concurrency Concurrent numbering can become very common in jurisdictions that allow it. Where multiple routes must pass between

13158-523: The old US 40/ US 99E freeway, the current I-80 Bus , while, a year later, I-80 was proposed to be realigned along a new freeway that would run south of the former I-80/I-880 northeast of Sacramento, run to south of the American River , and rejoin I-80. This was necessary because the 1964 I-80 failed to meet Interstate standards . In 1972, I-880 was completed, while a part of the new alignment of I-80

13287-561: The original Interstate Highway System was proclaimed complete in 1992, despite deviations from the original 1956 plan and several stretches that did not fully conform with federal standards . The construction of the Interstate Highway System cost approximately $ 114 billion (equivalent to $ 618 billion in 2023). The system has continued to expand and grow as additional federal funding has provided for new routes to be added, and many future Interstate Highways are currently either being planned or under construction. Though heavily funded by

13416-460: The planners suggested an underground road running more than 0.5 miles (0.80 km) from Laguna to Divisadero streets. However, the roads would violate the long-standing general plan for San Francisco, which calls for no new highway capacity. In March 2015, this proposed route was adopted by the California Transportation Commission (CTC). Prior to the construction of I-80, the US 40 corridor suffered from frequent car accidents. Reasons included

13545-633: The planning phase between them. In 1966, the FHWA designated the entire Interstate Highway System as part of the larger Pan-American Highway System, and at least two proposed Interstate expansions were initiated to help trade with Canada and Mexico spurred by the North American Free Trade Agreement (NAFTA). Long-term plans for I-69 , which currently exists in several separate completed segments (the largest of which are in Indiana and Texas ),

13674-411: The prefix H . There are three one-digit routes in the state ( H-1 , H-2 , and H-3 ) and one auxiliary route ( H-201 ). These Interstates connect several military and naval bases together, as well as the important communities spread across Oahu, and especially within the urban core of Honolulu . Both Alaska and Puerto Rico also have public highways that receive 90 percent of their funding from

13803-537: The province's only concurrency between two 400-series highways . The concurrency was not in the original plan which intended for both the QEW and Highway 403 to run parallel to each other, as the Hamilton–Brantford and Mississauga sections of Highway 403 were initially planned to be linked up along a corridor (later planned to be tolled ) now occupied by Highway 407 . To avoid forcing drivers to pay tolls to use

13932-472: The roads is considered the main ("source") road and the others as the péaging (guest) roads. The official road map enables a maximum of five concurrent routes of the intrastate numbering system. Cycling routes and hiking routes are often concurrent. In Israel, two freeways , the Trans-Israel Highway (Highway 6), and Highway 1 run concurrently just east of Ben Shemen Interchange . The concurrency

14061-487: The route of present-day I-80 Bus , which was I-80 from 1957 to 1981, when I-80 was realigned along former I-880, routing along what was then the outskirts of Sacramento. US 40 then closely followed I-80 through the Sierra Nevada into Nevada. A portion of old US 40 near Donner Lake is still intact and is an alternate route of I-80. It begins near Soda Springs and ends at Truckee . At one point, it travels right by Donner Lake, unlike I-80, which ascends higher in

14190-524: The route, without regard to the route number. For instance, I-190 in Massachusetts is labeled north–south, while I-195 in New Jersey is labeled east–west. Some looped Interstate routes use inner–outer directions instead of compass directions, when the use of compass directions would create ambiguity. Due to the large number of these routes, auxiliary route numbers may be repeated in different states along

14319-434: The routes has its exit numbers dominate over the other and can sometimes result in having two exits of the same number, albeit far from each other along the same highway. An example of this is from the concurrency of I-94 and US 127 near Jackson , Michigan. The concurrent section of freeway has an exit with M-106 , which is numbered exit 139 using I-94's mileage-based numbers. US 127 also has another exit 139 with

14448-419: The same numbers, which is generally disallowed under highway administration guidelines. Several two-digit numbers are shared between unconnected road segments at opposite ends of the country for various reasons. Some such highways are incomplete Interstates (such as I-69 and I-74 ) and some just happen to share route designations (such as I-76 , I-84 , I‑86 , I-87 , and I-88 ). Some of these were due to

14577-734: The same roadway (and vice versa), is the only wrong-way concurrency in British Columbia. Concurrencies are also very common in Quebec . Most notably, the Samuel-de-Champlain Bridge features a concurrency with three Autoroutes: A-10 , A-15 , and A-20 . Another example is A-55 , which runs concurrently with A-10, A-20, and A-40 , all of which are major highways. In Ontario , the Queen Elizabeth Way and Highway 403 run concurrently between Burlington and Oakville , forming

14706-503: The same roadway are signed as traveling in opposite directions; one such wrong-way concurrency is found between Wytheville and Fort Chiswell , Virginia, where I‑81 north and I‑77 south are equivalent (with that section of road traveling almost due east), as are I‑81 south and I‑77 north. Auxiliary Interstate Highways are circumferential, radial, or spur highways that principally serve urban areas . These types of Interstate Highways are given three-digit route numbers, which consist of

14835-652: The same time, there could be an extension of another highway designation that is used to replace the newly shortened designation with another one. Between states, US 27 in Michigan previously ran concurrently with I-69 from the Michigan–Indiana state line to the Lansing, Michigan , area. From there it turned northwards to its terminus at Grayling . In 1999, the Michigan and Indiana departments of transportation petitioned

14964-586: The southern end of the US 127 business loop in Mount Pleasant , Michigan. (US 127's mile markers in Michigan reflect the cumulative distance north of the Ohio state line; the numbers resume north of the I-94 overlap and reflect the distance accumulated on that concurrency.) However, there are also instances where the dominant exit number range is far more than the secondary route's highest exit number, for example

15093-483: The then-new I-80 freeway. The new route also made traveling across the Sierra Nevada far easier. Before construction, US 40 was a two-lane undivided highway with winding turns. This route was often closed in the winter because of the high elevation of the Donner Pass (7,239 feet (2,206 m)), and drivers had to use a much longer route to the north, US 40 Alternate (US 40 Alt), now SR 70 , using

15222-490: The war, complied by submitting a detailed network of 20,000 miles (32,000 km) of interconnected primary highways—the so-called Pershing Map . A boom in road construction followed throughout the decade of the 1920s, with such projects as the New York parkway system constructed as part of a new national highway system. As automobile traffic increased, planners saw a need for such an interconnected national system to supplement

15351-534: Was adding on to the already increased number of US Routes and state highways . In result, the 1964 renumbering truncated US 50 to West Sacramento . The entire route of US 40 was deleted in the Western United States due to the completion of I-80. Also, the number "40" was duplicated along I-40 , at that time, a newly built route in Southern California . I-40 was to be numbered I-30 , but

15480-490: Was built along the corridor of US Route 40 (US 40), eventually replacing this designation entirely. The prior US 40 corridor itself was built along several historic corridors in California, notably the California Trail and Lincoln Highway . The route has changed from the original plans in San Francisco due to freeway revolts canceling segments of the originally planned alignment. Similarly in Sacramento ,

15609-466: Was chosen for the Interstate because of more gradual approaches that aided construction to Interstate Highway standards , which do not allow the sharp curves used by the Donner Pass Road. The grade is three to six percent for 30 miles (48 km). In California I-80 was built along the line of, and eventually replaced, US 40 . The US 40 designation was eliminated in the state as part of

15738-551: Was completed but not open to traffic, where there was a long bridge to nowhere. From 1972 to 1980, I-880 began in West Sacramento as a fork from the original I-80, continues northeast over the Sacramento River to its interchange with I-5 , continues east through the communities of North Sacramento and Del Paso Heights , and ends at an interchange with the Roseville Freeway (I-80). The now-designated Capital City Freeway

15867-479: Was deleted in 1991), and the remainder were already in use by the other aforementioned auxiliary routes. (I-880 was designated at the same time as I-238.) One business loop of I-80 exists in California, running along a former alignment through Sacramento . Three former auxiliary Interstate Highway routes exist: Interstate Highway System [REDACTED] The Dwight D. Eisenhower National System of Interstate and Defense Highways , commonly known as

15996-541: Was employed ahead of Hurricane Charley in the Tampa, Florida area and on the Gulf Coast before the landfall of Hurricane Ivan ; however, evacuation times there were no better than previous evacuation operations. Engineers began to apply lessons learned from the analysis of prior contraflow operations, including limiting exits, removing troopers (to keep traffic flowing instead of having drivers stop for directions), and improving

16125-485: Was not a freeway in that access was at intersections with adjoining streets rather than by ramps. The Eastshore Highway ran from El Cerrito to the San Francisco–Oakland Bay Bridge along the same routing as today's freeway, although it was much narrower. A causeway was constructed for this purpose by filling in part of the mudflats along the bayshore. In the stretch from University to Ashby avenues in Berkeley , this resulted in

16254-422: Was proclaimed complete in 1992, but two of the original Interstates— I-95 and I-70 —were not continuous: both of these discontinuities were due to local opposition, which blocked efforts to build the necessary connections to fully complete the system. I-95 was made a continuous freeway in 2018, and thus I-70 remains the only original Interstate with a discontinuity. I-95 was discontinuous in New Jersey because of

16383-540: Was removed, the highway north of the Lansing area was renumbered US 127, and the US 27 designation was removed from I-69. Some consolidation schemes involve the use of incorporating two single-digit numbers onto one marker, as along the US 1/9 concurrency in northern New Jersey . In the mid-20th century, California had numerous concurrencies, but the California Legislature removed most of them in

16512-494: Was serving as Supreme Commander of Allied Forces in Europe during World War II . In 1954, Eisenhower appointed General Lucius D. Clay to head a committee charged with proposing an interstate highway system plan. Summing up motivations for the construction of such a system, Clay stated, It was evident we needed better highways. We needed them for safety, to accommodate more automobiles. We needed them for defense purposes, if that should ever be necessary. And we needed them for

16641-575: Was then the original I-80 routing, continuing southwest directly into downtown Sacramento. I-80 was then rerouted along the Beltline Freeway in 1983, while the Capital City Freeway became I-80 Bus, also I-305 and SR 51. I-880 would have intersected SR 244 and then US 50 , but, in 1979, the Sacramento City Council voted to delete the proposed I-80 alignment for rail transit. The constructed I-80/SR 51/SR 244 split

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