Speed limits in the United States
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Speed limits in the United States are set by each state or territory. Speed limits are always posted in increments of five miles per hour. Some states have lower limits for trucks and at night, and occasionally there are minimum speed limits. Most speed limits are set by state or local statute, although each state allows various agencies to set a different, generally lower, limit.
The highest speed limits are generally 75 mph (121 km/h) in western states and 70 mph (113 km/h) in eastern states. A few states, mainly in the Northeast Megalopolis, have 65 mph (105 km/h) limits, and Hawaii only has 60 mph (97 km/h) maximum limits. Small portions of the Texas, Wyoming, and all of Utah's road networks have higher limits, and Idaho has passed legislation to raise some freeway speed limits to 80 mph. For 13 years (1974–1987), federal policy forced states to adopt speed limits of 55 mph (89 km/h) or less.
- 1 Overview
- 2 History
- 3 Minimum speed limits
- 4 Truck speed limits
- 5 Night speed limits
- 6 Political considerations
- 7 Jurisdictional distinctions
- 7.1 Alabama
- 7.2 Alaska
- 7.3 Arizona
- 7.4 Arkansas
- 7.5 California
- 7.6 Colorado
- 7.7 Connecticut
- 7.8 Delaware
- 7.9 Florida
- 7.10 Georgia
- 7.11 Hawaii
- 7.12 Idaho
- 7.13 Illinois
- 7.14 Indiana
- 7.15 Iowa
- 7.16 Kansas
- 7.17 Kentucky
- 7.18 Louisiana
- 7.19 Maine
- 7.20 Maryland
- 7.21 Massachusetts
- 7.22 Michigan
- 7.23 Minnesota
- 7.24 Mississippi
- 7.25 Missouri
- 7.26 Montana
- 7.27 Nebraska
- 7.28 Nevada
- 7.29 New Hampshire
- 7.30 New Jersey
- 7.31 New Mexico
- 7.32 New York
- 7.33 North Carolina
- 7.34 North Dakota
- 7.35 Ohio
- 7.36 Oklahoma
- 7.37 Oregon
- 7.38 Pennsylvania
- 7.39 Puerto Rico
- 7.40 Rhode Island
- 7.41 South Carolina
- 7.42 South Dakota
- 7.43 Tennessee
- 7.44 Texas
- 7.45 US Virgin Islands
- 7.46 Utah
- 7.47 Vermont
- 7.48 Virginia
- 7.49 Washington
- 7.50 West Virginia
- 7.51 Wisconsin
- 7.52 Wyoming
- 8 See also
- 9 Notes
- 10 References
This table contains the most usual daytime speed limits, in miles per hour, on typical roads in each category. The values shown are not necessarily the fastest or slowest. They usually indicate, but not always, statutory speed limits. Some states and territories have lower truck speed limits applicable to heavy trucks. If present, they are usually only on freeways or other high speed roadways.
Divided rural: State or U.S. route, generally with four or more lanes, not built to Interstate standards, but with a median or other divider separating directions of travel.
Undivided rural: County, State, or U.S. route, generally with two to four lanes, with no separator between directions of travel.
Residential Street/residential: Residential streets, business districts, or School zones.
|State or territory||Freeway (rural)||Freeway (trucks)||Freeway (urban)||Divided (rural)||Undivided (rural)||Residential|
|District of Columbia||–||–||50–55||–||–||15–25|
|State or territory||Freeway (rural)||Freeway (trucks)||Freeway (urban)||Divided (rural)||Undivided (rural)||Residential|
|U.S. Virgin Islands||–||–||–||55||35||20|
Freeway: Interstate Highway or other state- or federally numbered road built to Interstate standards.
Divided: State- or federally numbered road, generally with four or more lanes, not built to Interstate standards, but with a median or other divider separating directions of travel.
Undivided rural: County, State, or U.S. route, generally with two to four lanes, with no separator between directions of travel.
Residential Street/residential: Residential streets, business districts, or School zones.
|State||Typical fine||Recklessness threshold or enhanced penalty||Absolute/prima facie||Ticket dismissal options||Point system|
|North Carolina||$10–$50 plus court costs. Speeding fines in work zones and school zones are $250 plus court costs.||>15 mph over limit (at a travelled speed of 55 mph or greater) or over 80 mph||Absolute||Prayer for judgment continued (PJC) available depending on the court and subject to their discretion, but not available for charges of exceeding a speed limit by more than 25 mph.||Point system may lead to license suspension. Exceeding the speed limit by more than 15 mph with a speed of 55 mph or greater or travelling faster than 80 mph results in a minimum 30-day license suspension.|
|Pennsylvania||$35 plus court and other costs. All fines doubled in active work zones.||>30 mph over limit||Absolute||None||Point system leads to mandatory driver education and possible license suspension.|
|Texas||$1–$200 plus court fees. Doubled in active school zone or construction zone when workers are present. Various additional "fees" assessed by the state essentially increase the fine by around $100 on all tickets.||None||Prima facie||Defensive driving (once per year) or deferred disposition (restrictions vary, but generally at least 4 per year), but only valid if:
||Point system is annual surcharge only. No provision for license suspension.|
|Rhode Island||Prima facie||One dismissal every 3 years for speed 14 mph or less over limit.|
|Virginia||20 mph over limit or over 80 mph or.||Absolute||Point system leading to fines, suspension, and mandatory driver education.|
The first speed limit in the United States was set in Boston in 1757: by the board of selectmen (i.e. a sort of city council). The speed limit for wagons, carriages, horses, etc. on Sunday was set at a walking pace. Anyone exceeding this limit would be fined 10 shillings (equal to £58.51 today).
Minimum speed limits
In addition to the legally defined maximum speed, minimum speed limits may be applicable. Occasionally, there are default minimum speed limits for certain types of roads, generally freeways.
Comparable to the common basic speed rule, most jurisdictions also have laws prohibiting speeds so low they are dangerous or impede the normal and reasonable flow of traffic.
Truck speed limits
Some jurisdictions set lower speed limits that are applicable only to large commercial vehicles like heavy trucks and buses. While they are called "truck speed limits", they generally do not apply to light trucks.
Because trucks, considered as class 7 and 8, are far heavier than other vehicles, they take longer to stop, are less adept at avoiding hazards, and have much more momentum. Therefore, it follows from basic physics that limiting truck speeds could reduce the severity and incidence of truck-related crashes.
However, the research record is mixed. A 1987 study finds that crash involvement significantly increases when trucks drive much slower than passenger vehicles, suggesting that the difference in speed between passenger vehicles and slower trucks could cause crashes that otherwise may not happen. Furthermore, in a review of available research, the Transportation Research Board (part of the United States National Research Council) states "[no] conclusive evidence could be found to support or reject the use of differential speed limits for passenger cars and heavy trucks" (page 11) and "a strong case cannot be made on empirical grounds in support of or in opposition to differential speed limits" (page 109).
Two thirds (67%) of truck/passenger car crashes are the fault of the passenger vehicle.
Night speed limits
The basic speed rule requires drivers adjust speeds to the conditions. This is usually relied upon to regulate proper night speed reductions, if required. Numeric night speed limits, which generally begin 30 minutes after sunset and end 30 minutes before sunrise, are occasionally used where, in theory, safety problems require a speed lower than what is self-selected by drivers.
- Some streets in Tucson, Arizona without street lights.
- Some Florida roads near SW Florida Int'l Airport near Cape Coral/Fort Myers. (Most of these roads are labeled as "Panther Zones" or "Panther X-ing" areas.)
- Daniels Parkway Ext., a 4 lane divided Hwy near SW Fl Int't Airport with 50 mph daytime limit, and a night speed limit of 45 mph is considered by many to be a speed trap. This road joins neighboring SR 82, a 2 lane road with a 60 mph speed limit.
- Colorado Highway 13, with a 65 mph day/55 mph night speed limit beginning 7.1 mi. north of I-70 from north of Rifle to CO. Hwy. 64 south of Meeker. Rural Colorado Hwy. 13 is 55 mph at night north of Meeker all the way to the Wyoming state line.
Some states create arbitrary night speed limits applicable to entire classes of roads. Until September 2011, Texas had a statutory 65 mph night speed limit for all roads with a higher limit. Montana has a statutory 65 mph night speed limit on all federal, state, and secondary roads except for Interstates.
Subjective or political influence on speed limits is evident by state-to-state speed limit variances that have no empirical justification. Highlighted examples include:
- All 51 miles (82 km) of I-95 in Pennsylvania are posted at 55 mph, while in neighboring New Jersey, the speed limit on I-95 is primarily 65 mph, despite their common suburban environment.
- I-84 in New York State from the Connecticut state line to the New York State Thruway has a speed limit of 55 mph (the section from I-684 to the Hudson River was increased to 65 mph in 2010), even though connecting I-684 has a 65 mph limit and the population/traffic density is no different on either road (I-84 also has a 65 mph limit in Connecticut east of the bordering city of Danbury).
- Interstate 95 from the Newark Toll Plaza south of Exit 1 at DE 896 to the Maryland State line is 55 mph. The speed limit goes up to 65 mph at the Maryland State line. The stretch of roadway between Exit 109 at MD 279 and prior to Exit 1 at DE 896 before the Newark Toll Plaza are identical roadways.
- The lowest class of state-maintained, two-lane road in Texas may have a 75 mph speed limit, but a two-lane US highway built to neighboring Arkansas's or Louisiana's highest standards may not have a speed limit over 55.
- Trucks traveling westbound on I-10 or I-40 from Arizona (which has no separate truck speed limit) into California see their legal speed limit drop from 75 mph to 55 mph, despite similar road conditions.
- Only four states allow two-lane highways to be posted at 70 mph or higher: Idaho, Texas, Nevada, and Montana.
- Before night speed limits were abolished, Texas's rural Interstates highways generally had 65 mph night speed limits, but motorists were allowed to travel at 70 or 75 mph at night on all adjacent states' rural Interstates.
Even in-state examples point to arbitrariness. For example, I-10 and I-20 in far west Texas have had the following speed limits despite no significant changes in roadway characteristics:
- Before 1963: 60 mph day/55 mph night
- 1963–1974: 70 mph day/65 mph night
- 1974–1986: 55 mph
- 1986–1995: 65 mph
- 1995–2001: 70 mph day/65 mph night
- 2001–2006: 75 mph day/65 mph night
- 2006–2012: 80 mph day/65 mph night
- 2012–: 80 mph
Traffic violations can be a lucrative income source for jurisdictions and insurance companies. For example:
- Westlake, TX took in $42,000 per citizen over nine years for its speed traps.
- Insurance companies may receive several billions of dollars annually in traffic ticket surcharges.
- A study by the Federal Reserve of St. Louis found that traffic ticket writing increases when government revenue decreases.
- 2008 debates over traffic enforcement in Dallas County, TX involved concerns of lost profits if ticketwriting decreased.
Thus, an authority that sets and enforces speed limits, such as a state government, regulates and taxes insurance companies, who also gain revenue from speeding enforcement. Furthermore, such an authority often requires "all" drivers to have policies with those same companies, solidifying the association between the state and auto insurers. If a driver cannot be covered under an insurance policy because of high risk, the state will assume that high risk for a greater monetary amount; thus resulting in even more revenue generation for the state.
When a speed limit is used to generate revenue but has no safety justification, it is called a speed trap. The town of New Rome, Ohio was such a speed trap, where speeding tickets raised up to $400,000 per year to fund the police department of a 12-acre village with 60 residents.
Reduced speed limits are sometimes enacted for air quality reasons. The most prominent example includes Texas' environmental speed limits, which do not appear to significantly contribute to air quality.
Metric speed limits
Though not common in the United States, a speed limit may be defined in kilometers per hour (km/h) as well as miles per hour (mph). The Federal Highway Administration's Manual on Uniform Traffic Control Devices, which provides guidelines for speed limit signage, states that "speed limits shown shall be in multiples of 10 km/h or 5 mph." If a speed limit sign indicates km/h, the number is circumscribed and "km/h" is written below. Prior to 2003, metric speed limits were designated using the standard speed limit sign, usually with yellow supplemental "METRIC" and "km/h" plaques above it and below it, respectively.
The 1995 National Highway System Designation Act prohibited use of federal funds to finance new metric signage.
Federal speed controls
In response to the 1973 oil crisis, Congress enacted the National Maximum Speed Law that created the universal 55 miles per hour (89 km/h) speed limit. Whether this reduced gasoline consumption is debated and the impact on safety is unclear; studies and opinions of safety advocates are mixed.
The law was widely disregarded by motorists, even after the national maximum was increased to 65 miles per hour (105 km/h) on certain roads in 1987 and 1988. In 1995, the law was repealed, returning the choice of speed limit to each state.
Definition of speeding
Either of the following qualifies a crash as speed-related in accordance with U.S. government rules:
- Exceeding speed limits.
- Driving too fast for conditions.
Speeds in excess of speed limits account for most speed-related traffic citations; generally, "driving too fast for conditions" tickets are issued only after an incident where the ticket issuer found tangible evidence of unreasonable speed, such as a crash.
A criticism of the "exceeding speed limits" definition of speeding is twofold:
- When speed limits are arbitrary, such as when set through political rather than empirical processes, the speed limit's relationship to the maximum safe speed is weakened or intentionally eliminated. Therefore, a crash can be counted as speed-related even if it occurs at a safe speed, simply because the speed was in excess of a politically determined limit.
- The effective limit may still be too fast for certain conditions, such as limited visibility or reduced road traction or even low-speed truck rollovers on exit ramps.
Variable speed limits offer some potential to reduce speed-related crashes. However, due to the high cost of implementation, they exist primarily on freeways. Furthermore, most speed-related crashes occur on local and collector roads, which generally have far lower speed limits and prevailing speeds than freeways.
Most states have absolute speed limits, meaning that a speed in excess of the limit is illegal per se. However, some states have prima facie speed limits. This allows motorists to defend against a speeding charge if it can be proven that the speed was in fact reasonable and prudent.
A successful prima facie defense is rare. Not only does the burden of proof rest upon the accused, a successful defense may involve expenses well in excess of the cost of a ticket, such as an expert witness. Furthermore, because prima facie defenses must be presented in a court, such a defense is difficult for out of town motorists.
||It has been suggested that this section be split into a new article. (Discuss) Proposed since July 2014.|
In Alabama, trucks carrying hazardous materials are not to exceed 55 mph. A speed limit of 30 mph in urban areas and 35 mph on unpaved rural roads is enforced. The speed limit for county paved roads is 45 mph. All other 2 lane roads are limited to 55 mph. The interstate limit is 70 mph while other 4 lane highways are limited to 65 mph.
||It has been suggested that this section be split into a new article. (Discuss) Proposed since July 2014.|
In Alaska, several roads carry a 65 mph speed limit: a majority of the Parks Highway between Fairbanks and Willow (excepting slower zones through Nenana, Denali Park, Cantwell, and Healy), most of the Richardson Highway between Valdez and North Pole, a 52-mile stretch of the Glenn Highway between Wasila and Anchorage, parts of the Seward Highway freeway within South Anchorage, and other parts of the Seward Highway south of Girdwood. Engineering studies are needed to define which road segments to post a speed limit higher than 55 mph.
Speed limits in Alaska are 15 mph in alleys, 20 mph in a business district, 25 mph in a residential district, and 55 mph on other roads. The speed limit in all rural areas of Alaska is 55 mph unless otherwise posted, and the default limit on a rural 2-lane highway is 55 mph. The speed limit when towing a mobile home is 45 mph.
||It has been suggested that this section be split into a new article. (Discuss) Proposed since July 2014.|
The default speed limit outside of "business or residential" districts in Arizona is 65 mph, within those districts the default speed limit is 25 mph. The school zone speed limit is 15 mph, while some may be 25 to 35 mph. Exceeding these limits only in the best of driving conditions is considered prima facie evidence of speeding. Altered speed limits are not prima facie.
The maximum speed limit on Interstate Highways is 75 mph. This limit may be applied outside of "urbanized areas", where speeds of over 85 mph on any highway is considered "excessive". Within "business or residential" districts, exceeding the speed limit by more than 20 mph is considered "excessive". Within "urbanized areas", 55 mph speed limit citations are given for "waste of a finite resource". This exception only applies within a 10 mph threshold. As long as the speed does not exceed 65 mph, the infraction is not recorded as a traffic violation for the purposes of a point system.
Non-passenger vehicles in excess of thirteen tons, or "vehicles drawing a pole trailer" weighing more than 3 tons may not exceed 65 mph unless signs are posted that allow such a speed. Yet this does not differ from the default speed limit, and has the practical effect of requiring extra consideration for posting a standard speed limit sign in excess of 65 mph. A non-numeric minimum speed limit is incorporated with the basic speed rule in Arizona, which also prohibits speeds higher than would be "reasonable and prudent".
Night speed limit signs are posted on some roads within Tucson city limits that do not have street lights. Examples: Fort Lowell Road from Oracle Road to Country Club Road, 22nd Street from I-10 to Cherry Avenue.
Urban districts by default are posted at 30 mph. Outside of the municipal limits, a two-lane road are by default is posted at 55 mph. Recently, the Arkansas High Commission has authorized the Arkansas AHTD to raise the speed limit on undivided 4 and 5 lane roads from 55 to 60 mph while divided 4 lane roads are set to go from 55 to 65 mph. Furthermore, AHTD has established freeway default speed limits. Along rural freeways, 70 mph while suburban freeways are 60 mph. Unlike most states, a licensed Arkansas motorist has to accumulate at least 14 but no more than 17 driver license points to get a 3–6-month license suspension.
Basic speed law
California's "Basic Speed Law", part of the California Vehicle Code, defines the maximum speed at which a car may travel as a "reasonable and prudent" speed, given road conditions. The reasonable speed may be lower than the posted speed limit in conditions such as fog, heavy rain, ice, snow, gravel, sharp corners, blinding glare, darkness, crossing traffic, or when there is an obstructed view of orthogonal traffic—such as by road curvature, parked cars, vegetation, or snow banks—thus limiting the Assured Clear Distance Ahead (ACDA). Basic speed laws are statutized reinforcements of the centuries-old common law negligence doctrine as specifically applied to vehicular speed. California Vehicle Code section 22350 is typical; it states that "No person shall drive a vehicle upon a highway at a speed greater than is reasonable ... and in no event at a speed which endangers the safety of persons or property".
Speed limits in California are mandated by statute to be set: (1) at or below the 85th percentile operating speed;  as determined by a traffic and engineering survey—this is the speed which no more than 15% of traffic exceeds; or (2) the prima facie limits mandated when certain criteria are met as described in the vehicle code. These criteria include school zone, alleyway, and residential area.    
If the 85th percentile operating speed as measured by a Traffic and Engineering Survey exceeds the design speed, compulsory legal protection is given to that speed—even if it is unsafe with regard to certain technical aspects such as sight distance. This speed creep may continue until the 85th percentile operating speed is comparable to speed psychologically perceived as uncomfortably hazardous.
The theory behind California's 85th percentile statute is that, as a policy, most of the electorate should be seen as lawful, and limits must be practical to enforce. However, there are some circumstances where motorists do not tend to process all the risks involved, and as a mass choose a poor 85th percentile speed. This rule in substance is a process for voting the speed limit by driving; and in contrast to delegating the speed limit to an engineering expert.[Note 1]
Many speed limit signs are identified as "maximum speed", usually when the limit is 55 mph (89 km/h) or more. When the National Maximum Speed Law was enacted, California was forced to create a new legal signage category, "Maximum Speed", to indicate to drivers that the Basic Speed Law did not apply for speeds over the federally mandated speed cap; rather, it would be a violation to exceed the fixed maximum speed indicated on the sign, regardless of whether the driver's speed could be considered "reasonable and prudent".
A driver can receive a traffic citation for violating the Basic Speed Law even if their speed is below the "maximum speed limit" if road, weather, or traffic conditions make that speed unsafe. However, because the Basic Speed Law establishes prima facie limits, not absolute ones, they can also defend against a citation for speeding "by competent evidence that the speed in excess of said limits did not constitute a violation of the basic speed law at the time, place and under the conditions then existing," per section 22351(b) of the California Vehicle Code. As attorney David W. Brown says in his book Fight Your Ticket & Win in California, "a person traveling over the speed limit–but less than the usual 65 mph maximum speed (55 mph for two-lane undivided highways)–isn't necessarily violating the law" and that "you can defend against a charge of violating the Basic Speed Law not only by showing you weren't exceeding the speed limit, but also by establishing that even if you were over the limit, your speed was nevertheless 'safe' under the circumstances."
Rural freeways, such as parts of I-5, I-8, I-10, I-15, I-40, and U.S. 101 on the central coast, and SR 99 south of Madera and Fresno, have 70 mph (113 km/h) speed limits. Because I-80 passes exclusively through urban and mountainous areas, its highest speed limit is only 65 mph. In downtown Los Angeles, the maximum speed limit is 55 mph. This includes the entire length of the Pasadena Freeway between Pasadena and downtown Los Angeles, and portions of the Hollywood, Santa Ana, Santa Monica, and Harbor Freeways. The default limit on 2-lane roads is 55 mph. However, Caltrans or a local agency can post a speed of up to 65 mph after an engineering study.
All of these highways feature supplementary signage stating "AUTOS WITH TRAILERS/TRUCKS 55 MAXIMUM". Maximum truck/autos with trailers limit applies to trucks with 3 or more axles and all vehicles when towing. As of 2007, these signs are being replaced with signage stating "ALL VEHICLES WHILE TOWING 55 MAXIMUM".
The maximum speed limit in Colorado is 75 MPH on rural Interstate highways. Interstate 70 in the Rocky Mountains has a 65 MPH limit due to steep grades and curves and a 50 MPH limit at the east and west ends of the Eisenhower Tunnel. The maximum speed limit on other rural highways is 65 MPH.
There are also basic prima facie speed limits in Colorado.
- 20 MPH on narrow, winding mountain roads
- 25 MPH in any business district
- 30 MPH in any residential district
- 40 MPH on open mountain highways
Night Speed Limits
On certain stretches of rural highways, notably US-160 between Durango and Pagosa Springs and US-550 between Durango and Silverton, nighttime speed limits are in effect during peak migratory periods for area wildlife. Speeding fines are doubled when nighttime speed limits are in effect.
Speed limits in Connecticut are normally 65 MPH on rural freeways; up to 55 MPH on rural divided and undivided highways. In urban areas speed limits vary from 25 MPH on residential streets and central business districts to 30–40 MPH on arterial roadways, and from 45 to 55 MPH on urban freeways. Limited-access divided highways have a minimum speed of 40 mph (64 km/h), but this is not always posted.
Speed limits for all roads within Connecticut—including local streets—are established by the State Traffic Commission, an agency composed of members of the Department of Motor Vehicles (CTDMV), the Department of Emergency Services and Public Protection (DESPP), and the Department of Transportation (CONNDOT).
The State Traffic Commission typically sets speed limits following engineering studies performed by CONNDOT. Data used in setting speed limits includes: traffic volume vs. roadway capacity, design speed, road geometry, spacing of intersections and/or interchanges, number of driveways and curb cuts, and accident rates.
Municipalities are normally required to seek approval from the State Traffic Commission for changes to the posted speed limits on locally owned streets after appropriate engineering studies are performed.
Speeding fines are doubled in school zones when children are present, and construction areas when workers are present.
Prior to 1974, Connecticut permitted a maximum speed of 70 MPH on rural freeways.
In Delaware, only two roads have a 65 mph (105 km/h) speed limit: I-495 and the toll road portion of Delaware Route 1. Interstate 95 is 55 mph (89 km/h) and Interstate 295 is 50 mph (80 km/h). Prior to the National Maximum Speed Law that went into effect nationwide, I-95 used to have a 60 mph speed limit except around Wilmington.
All rural two-lane state-owned roads have 50 mph (80 km/h) speed limits, while all urban speed limits, regardless of location, are held at 25 mph (40 km/h) for two-lane roads and up to 35 mph (56 km/h) for four-lane roads. Four lane highways such as US 13, US 113, portions of US 40 near Bear and Glasgow, and the at-grade portions of DE 1 are normally 55 mph.
School zones have 20 mph (32 km/h) speed limits.
Interstate 495, which forms a bypass around Wilmington, features changeable speed limit signs for environmental purposes. These signs typically display a 65 mph speed limit, but this limit changes to 55 mph on days when air quality is a concern. The limit is also lowered during construction and when accidents occur.
All neighborhoods and subdivisions in Delaware have a maximum speed limit of 25 mph as set by state law. Frequent ad campaigns on in-state radio stations remind residents of this (as of January 2013).
Florida raised its speed limit from the federally mandated 55 mph national limit (1974–1987) to 65 mph in 1987. In 1996, after the 1995 repeal of federal speed limit controls, Florida raised the speed limit to 70 mph on freeways, including rural Interstate Highways, and limited access toll roads; 65 mph on rural 4-lane highways (including US and State highways); and 60 mph on rural 2-lane highways. Florida was the first state entirely east of the Mississippi River where a speed limit greater than 55 was allowed on two-lane roads. 60 mph on two-lane roads is usually allowed on rural sections of United States Highways, most rural state highways and rarely, but sometimes posted on rural county roads. County roads typically have 55 mph or less speed limits.(One example of a rural CR with a rarely posted 60 mph speed limit is Glades CR 74, from SR 29 west to the Charlotte County line in South Florida. Once west of the Charlotte County line, the limit drops to 55 mph).
Florida typically does not post night speed limits, but there are a few exceptions. For the most part, these night time reduced speeds are located in wildlife preserves for such endangered species as the Florida panther and the key deer. Most of the Tamiami Trail through the Big Cypress National Preserve has a 45 mph night speed limit. On some stretches of road where the speed limit is reduced at night, the daytime speed limit sign is not reflective so at night, only the night limit is visible.
Florida's minimum speed limit on Interstate Highways is now posted at 50 mph in most 70 mph zones, up from the previous 40 mph minimum. In 55 mph, and 65 mph urban interstate zones, the minimum remains 40 mph.
The State of Florida also does not impose a lower truck speed limit. As such, all interstate traffic is permitted to travel at the same speed.
School zones in Florida usually have 10 mph to 20 mph limits. Most have flashing yellow lights activated during the times they are in effect as well as accompanying signs which post the times these reduced speed limits are effective. All are strictly enforced and carry an increased penalty for violations.
Interstates are posted at 70 mph. However, when an Interstate passes through a municipality or metropolitan area with a population over fifty thousand (except on freeways, portions of I-285 in the Atlanta area are also posted at 65 mph), state law requires the speed limit to be 55 mph. Despite that, it is still 65 mph on the Athens southern perimeter (US 78), I-95 through Brunswick, I-95 and I-16 through suburban Savannah, and I-185 in Columbus.
Four lane arterials and expressways can be posted as high as 65 mph. However, Dillon's Rule enables counties outside municipalities to keep four lane GRIP corridors at 55 mph. However, in recent years, US 1 between Augusta and Wrens raised the speed limit to 65 mph. Other rural four-lane highways with a 65 mph include portions of US 441 near Irwinton, US 25 between Augusta and Statesboro, State Route 88 between Sandersville and Wrens, much of US 341 between Brunswick and I-75, and much of US 82 in South Georgia.
Two lane state roads by default are posted at 55 mph. County maintained roads will rarely if they even do, post any roadway above 50 mph in middle & south Georgia, 45 mph in north Georgia. Both in the Atlanta area, Ronald Reagan Parkway is posted at 50 mph as a county maintained freeway and Sugarloaf Parkway is posted at 55 mph along its new eastern freeway portion.
Inside the municipality, speed limits are generally posted at 35 mph while it is 25–30 mph in the downtown area.
All roadways maintained by GDOT that are subject to speed limit reductions are given advanced notice with signage that says "REDUCED SPEED AHEAD". Furthermore, GDOT has a policy of doing 5 to 10 mph increments but never higher than 10 mph.
Georgia is one of few states with anti-speed trap laws passed in the late 1990s. Speed violations less than 15 mph over the speed limit will have no points assessed. Fines are not assessed for motorists going less than 10 mph over the speed limit.
Hawaii was the last state to raise its maximum speed limit after the National Maximum Speed Law was repealed in 1995. In 2002, following public outcry after a controversial experiment with speed enforcement using road safety cameras, the state Department of Transportation raised the speed limit to 60 mph on Interstate H-1 between Kapolei and Waipahu, and Interstate H-3 between the Tetsuo Harano Tunnels and the junction with H-1. All other freeways, including Interstate H-2, have a maximum speed limit of 55 mph, with the limit dropping to 45 mph in central Honolulu. Other highways generally have speed limits of 55 mph and in many cases much less.
Hawaii has a minimum speed along much of Interstate H-1 of only 10 mph below the speed limit. The minimum speed is usually 45 mph when the speed limit is 55, and 40 mph when the speed limit is 50.
The speed limit on a freeway in Idaho is 80 mph rural, 65 mph urban, and a 70 mph truck speed limit. Generally both 2- and 4-lane highways have 70 limits, and roads with traffic lights are posted at 60 or below. The school zone speed limit in Idaho is 25 mph, (Except Grangeville, ID, in which it is 15 mph).
Idaho senator Bart Davis brought SB 1284a to the House for discussion in early 2014. The bill passed the Senate on February 25 and was signed into law by Governor Otter on March 18, 2014, which was set to raise the speed limit on rural interstates to 80 mph on July 1, 2014, the same date Wyoming raised its speed limit. Days before the law was to go into effect, however, it was put on hold in order to allow a more thorough review of the effects of a raised speed limit. A vote on July 14th, 2014 approved the 80 mph increase on limited sections of interstates in the southern portions of Idaho. Studies will begin for other areas later this summer. The bill also would raise truck and two-lane highway speed limits to 70 mph. As of July 24, 2014, the new 80 mph signs are up on rural Idaho Interstates.
Interstate Highways in Illinois are usually posted with both minimum and maximum speed limits, except in some urban areas, particularly Chicago. Most expressways in Cook, DuPage, and Lake Counties, and some expressways in Will County maintain a 55 mph speed limit. Due to the high population density, the only expressways in Cook County that exceed a speed limit of 55 mph are I-80 at the southern edge of the county, and part of I-57 between Central Ave. and Harlem Ave. In downtown Chicago, where all the major expressways merge, the speed limit is reduced to 45 mph due to high-traffic density and frequent entering/exiting of the expressways. All other freeways in Illinois maintain a 70 mph speed limit, except in areas approaching a major city where the speed limit may be reduced to 55-65. As of January 2010, a reduced speed limit posted in a construction zone must be obeyed 24 hours a day, regardless of whether workers are present.
A bill passed by the Governor Pat Quinn restored the speed limit on rural interstates back to 70 mph, but allowed the 6 county Chicago region and 2 counties near St. Louis, MO to opt out of the higher speed limit. No county has adopted an ordinance to establish a lower speed limit yet. The change went into effect on January 1, 2014. Before the NMSL, Illinois had 70 mph speed limits on freeways and expressways, and 65 mph limits on two-lane roads. Bills that are similar to SB2356 were introduced in 2010 and 2012.
The former 55 mph truck speed limit has been removed with the exception of Cook, DuPage, Lake, Kane, Will, and McHenry Counties. In those areas it is either too crowded or the road too congested for trucks to be traveling in excess of 55 mph.
The minimum speed limit in Illinois is 45 mph with the following exceptions:
- Minimum speed limits don't apply to most urban areas, including the Chicago area.
- Rural speed limits changed to 70 on January 1, 2014.
In Indiana speed limits on Interstate Highways are usually 70 mph (113 km/h) for cars and 65 mph (105 km/h) for trucks with a gross vehicular weight (GVW) of 13 tons or greater, except in urban areas, where it is generally 55 mph (89 km/h) in city centers (except stretches of I-70 in Indianapolis where it is 50 mph) and 65 mph (105 km/h) cars/60 mph (95 km/h) trucks in suburban areas. The 65/truck: 60 signs are posted only for a short distance on freeways within Marion County in the Indianapolis area. Prior to July 5, 2005, all Interstate Highways were 65 mph and below.
Most non-Interstate Highways are 55 mph, but some rural four-lane divided highways (such as rural stretches of U.S. 31, U.S. 40 and U.S. 41, among others) are set at 60 mph. These limits often decrease to 30–50 mph (48–79 km/h) approaching urban areas, and within cities a speed limit of 20–30 mph (32–48 km/h) is not uncommon, though larger arterial roads within cities may reach as high as 45 mph (72 km/h). On February 6, 2012 the Indiana toll road was raised from the Illinois state line to mile marker 20 to 70 mph after a major highway reconstruction project.
Iowa's rural Interstate's speed limits are typically 70 mph (113 km/h), with no distinction made for trucks. Urban Interstate speed limits are usually set at 65 mph (105 km/h), with 55 mph speed limits set within cities, such as Interstate 235 in Des Moines and I-380 in Cedar Rapids. The Iowa DOT just recently increased the suburban speed limit on Interstate 235 to 60 mph, with 55 mph still effective for the downtown Des Moines area; 60 mph speed limits also exist on IA 58 and US 218 in Cedar Falls/Waterloo and on Interstate 380 outside of downtown Cedar Rapids.
Non-Interstate divided highways are signed at 65 mph with speeds dropping to 55 mph in urban areas. Two lane rural state and county highways have a 55 mph speed limit. The Interstate 74 bridge from Bettendorf to Moline, Illinois, has a 50 mph limit; the bridge is much narrower than normal and shoulderless.
Rural Interstates have a minimum speed limit of 40 mph, and U.S. Highway 20 between Interstate 35 and Dubuque also has a 40 mph minimum speed, alongside a 65 mph maximum. Other four-lane divided rural highways are signed at 65 mph, with no minimum speed (with the purpose of allowing slow-moving farm vehicles to use the road as well).
After the National Maximum Speed Limit was repealed, Kansas raised its general interstate speed limit to 70 mph (110 km/h); a study found "no statistically significant increases in crash, fatal crash and fatality rates were noted during the after period on either rural or urban interstate highway networks. On the other hand, statistically significant increases in crash, fatal crash and fatality rates were observed on the 2-lane rural highway network.". In 2011 Governor Sam Brownback signed legislation raising Kansas' top speed limit to 75 mph (121 km/h) on divided four-lane highways, effective July 1, 2011. The Kansas Department of Transportation announced on June 21, 2011, that 807 miles of roadway, comprising the rural areas of I-70, I-35, I-135, the Kansas Turnpike and the freeway-improved sections of US-69 and US-81, will be raised to 75 mph. Prior to the National Maximum Speed Limit, the speed limit on the Kansas Turnpike was 80 mph (130 km/h), but reduced to 75 mph on 17 August 1970.
The 75-mph speed limit on most of Interstate 70 matches that of neighboring Colorado. However, motorists driving into Oklahoma on Interstate 35 must drop their speed from 75 to 70, since Oklahoma's 75-mph limit applies only to turnpikes.
In July 2007, Kentucky raised its rural freeway speed limits from 65 to 70 mph. Kentucky does still have limits of 55 on multi-lane highways in some urban areas (I-71/75 near Cincinnati, I-64, I-65, I-71 and I-264 in Louisville, U.S. 60 bypass in Owensboro), and KY 4 in Lexington. There are two 50 mph areas in Louisville. One approaching the Sherman Minton Bridge crossing the Ohio River into Indiana on I-64, and one approaching the Kennedy Bridge on I-65 towards Indiana. By state law, only Parkways and Interstates may post speed limits higher than 55 MPH, so all other highways, including both two-lane and four-lane divided highways, are limited to 55 MPH. Points are not assessed for speeds less than 10 mph over the speed limit only on limited access highways, or for tickets received by Kentucky licensed drivers out of state.
Louisiana's highest speed limit is 75 mph, found on about 200 miles of Interstate 49 in Saint Landry, Avoyelles, Evangeline, Rapides, Natchitoches, DeSoto and Caddo parishes. The 75 zone was established by the Louisiana Department of Transportation and Development in 2011 after a 2010 bill authorized the DOTD to implement 75 zones where proven to be safe.
A speed limit of 60 mph is posted on I-10 in Lake Charles, Baton Rouge, and from LaPlace to New Orleans, I-12 in Baton Rouge, I-20 in Shreveport and Monroe, I-49 in Alexandria and Shreveport, I-310 in Destrehan, I-220 in Shreveport, U.S. Routes 71 and 167 in Kingsville, LA 3132, and Interstates 110, 210, 510, 610, and 910.
Most two-lane highways in Louisiana have a maximum speed limit of 55 mph.
In August 2003, Governor Mike Foster announced speed and lane restrictions on trucks on the 18 mile (29 km) stretch of Interstate 10 known as the Atchafalaya Swamp Freeway. The restrictions lower the truck speed limit to 55 mph and restrict them to the right lane for the entire length of the elevated freeway.
There are exceptions to the basic highway and speed laws
Divided highways in rural areas have a 65 mph speed limits. Louisiana law R.S. 32:61(B) & 32:62(A) states;
65 MPH on other multi-lane divided highways which have partial or no control of access.
Louisiana operates under the reasonable and prudent basic law;
No person shall drive a vehicle at a speed greater than is reasonable and prudent under the conditions and potential hazards then existing, having due regard for the traffic on, and the surface and width of, the highway, and the condition of the weather. R.S. 32:64(A)
A person, who is operating a motor vehicle on a multilane highway at less than the normal speed of traffic, shall drive in the right-hand lane then available for traffic. R.S. 32:71(B)(1)
Maine carries the highest speed limit east of the Mississippi River, with Interstate 95 carrying a 75 mph limit between Old Town and Houlton. Sections of I-95 south of Old Town as well as 295 carry 70 mph limits, except for brief 55 zones in more populated areas. The Saco stub I-195 is 60 mph, and 395 is 60 mph in Bangor and 65 mph in Brewer.
LD 654, which passed both houses and was enacted without the governor's signature, permits the DOT to post 75 MPH limits on any Interstate in Maine. The Maine Turnpike Authority will be increasing speed limits to 70 on most rural sections of the Maine Turnpike, pending the required public hearing process. Maine is the only state fully east of the Mississippi River to have speed limits above 70 mph. As of May 27, 2014 the speed limit has been increased on I-295 from 65 mph to 70 mph from the Tukey Bridge in Portland to Gardiner. Portions of I-95 have been increased from 65 mph to 70 mph.
The speed limit on Maryland's Interstate Highways are posted by default at 65 mph. Maryland's urban freeways normally have speed limits of 55 mph (like I-495) or 60 mph, although some stretches are signed for 65 mph travel such as portions of I-95 and I-97 in and around the Baltimore suburbs. More restrictive limits are found on Interstate 83 south of North Avenue when approaching downtown Baltimore and on Interstate 68 through Cumberland, both sections being marked at 40 mph.
Four lane non-interstates and non-freeways are posted at 55 mph. This includes the expressway grade roadways like US 50 and US 301 east of the Bay Bridge, US 15 north of Frederick to the Pennsylvania state line, MD 404 around Denton and US 29 between I-495 and I-70.
Normally, speed limit drops are in 5 mph to 10 mph increments. However, one speed zone drops from 55 to 25 mph along US 301 southbound at the Nice Bridge for the toll plaza.
Two lane roads are generally posted at 50 mph but there are a handful of routes posted at 55 mph. It is more common to see 55 mph on the Eastern Shore than the Baltimore-Washington corridor and Western Maryland.
Urban and downtown speed limits are generally posted at 30 mph.
As prescribed by Massachusetts law, default speed limits are the following: 15 mph in the area of a vehicle (for example, an ice cream truck) which is selling merchandise and is displaying flashing amber lights; 20 mph in a school zone when children are present; 30 mph in a "thickly settled" or business district; 40 mph outside of a "thickly settled" or business district and 50 mph on a highway outside a "thickly settled" or business district. A select number of two-lane roads are posted at 55 mph. Freeway speed limits generally outside of a central business district and no major substandard engineering standards are posted at 65 mph. A “thickly settled district” is an area where building structures such as residential and commercial are less than 200 feet apart for a distance of mile or more. This can be subjective since a large part of eastern Massachusetts is built up with many different jurisdictions with different speed limits assigned.
Speed limits in Michigan are governed by Public Act 85 of 2006, which requires that speed limits be set (up to a maximum of 70 mph) using a formula based on the number of driveways and streets, or on the 85th percentile of free-flowing traffic, and if none those methods are used a 55 mph default applies. Freeways in Michigan are usually signed with both minimum and maximum speeds. Typically the freeway speed limit is 70 mph. The minimum speed is usually 45 to 55 mph for all vehicles, despite a maximum speed limit of 60 mph (55 mph on non-freeway roads that have a posted speed limit at 65 for cars) for trucks—effectively permitting trucks only a 5 mph range of legal speeds.
- Interstate speeds for passenger vehicles range from 55 mph to 70 mph.
- Interstate speeds for trucks and military vehicles is 60 mph
- If workers are present, then the speed limit is 45 mph.
Michigan has permitted 65 mph speed limits on some rural, divided non-limited access highways. A 20-mile stretch of US-127 between St. Johns and Ithaca, was posted at 65 mph. Michigan State Police determined that motorists along this gap between limited access segments were not slowing down, and since the State of Michigan has dragged its feet on completing the segment, the higher speed limit emerged as a compromise to allow a freer flow of traffic. The speed limit on US Highway 2 between Rapid River and Gladstone in the Upper Peninsula was raised from 55 to 65 m.p.h.
A 70 mph speed limit is only allowed on Minnesota's Interstates outside of urban areas. A speed limit of 55 mph is typically used in urban areas where a higher speed limit might be used, but traffic congestion or other reasons require a lower speed limit. Examples include I-94, I-35W and I-35E in and around Minneapolis, Moorhead and Saint Paul. 35E goes down to a speed limit of 45 mph in some areas of Saint Paul. A speed limit of 60 mph is typically used in suburban areas such as I-494 and I-694 loops in the Twin Cities metro area.
Non-Interstate divided highways (both freeways and rural expressways) such as sections of US-169, US-212, the divided sections of US-2 and most of US-10 have speed limits of 65 mph in rural areas and up to 55 mph in urban or suburban areas. Undivided sections have speed limits of 55 mph while most of US-71, the undivided section of US-2, and the undivided sections (as well as the short divided sections between them) of MN-60 have a limit of 60 mph. On October 21, 2013, MNDOT raised the speed limit on US Route 75, 59, and a 14-mile (23 km) stretch of Minnesota Hwy 7 between the latter 2 routes to 60 mph as well. (Source:http://www.bemidjipioneer.com/content/speed-limit-two-western-minnesota-highways-increased-60) County roads have speed limits of up to 55 mph for 2 lanes and 60 for divided sections. Recently, a Transportation Bill which was signed by Governor Mark Dayton will enable MN DOT to start posting 60 mph speed limits on any two lane road in Minnesota based on Traffic and Engineering Studies. Such studies needs to be completed by 2019 but can start posting 60 mph speed limits by July, 2014. Source: http://www.startribune.com/politics/statelocal/260601891.html
A speed limit of 70 mph is only allowed on Mississippi's rural freeways; only the Interstates (except I-110), U.S. Highway 78, Mississippi Highway 304, and a portion of U.S. Highway 82 have speed limits of 70 mph, with these lengths making up approximately 86% of the state's freeway mileage.
A speed limit of 65 mph is typically used on the state's four-lane divided highways, which include parts of the following roadways:
- U.S. Route 45 / U.S. Route 45 Alternate
- U.S. Route 49 / U.S. Route 49W
- U.S. Route 61
- U.S. Route 72
- U.S. Route 82
- U.S. Route 84
- U.S. Route 90
- U.S. Route 98
- U.S. Route 278
- MS 15
- MS 19
- MS 25
- MS 39
- MS 57
- MS 63
- MS 67
- MS 302
- MS 605
- MS 607
A speed limit of 60 mph is typically used in urban areas where a higher speed limit might be used, but traffic or geometric conditions constitute a lower speed limit, including the following areas:
- Interstate 20 in Vicksburg, from Jackson to Pearl, and Meridian
- Interstate 55 from Jackson to Ridgeland
- Interstate 59 in Laurel and Meridian
- U.S. Route 61 in Tunica Resorts
- U.S. Route 78 in New Albany
- U.S. Route 82 in Columbus
House Bill 3, passed during the 2008 First Extraordinary Session of the state legislature, permits speed limits up to 80 mph (130 km/h) on toll roads in the state; however, as of 2008[update], no such road has been constructed.
Mississippi has a minimum speed of 30 mph on four-lane U.S. highways when no hazard exists. Strangely, there is no law for the minimum speed of the state's growing number of four-lane state highways. The minimum is 40 mph on Interstate Highways and on four-lane U.S. designated highways which have a 70 mph speed limit. In 2004, Mississippi posted minimum speed limits (40 mph) on all rural Interstates, but this minimum speed limit was already state law before then.
Statutory speed limits in Missouri are as follows:
- Interstate highways and freeways in rural areas: 70 MPH
- Expressways in rural areas: 65 MPH (notable exceptions being the US 54 & US 63 Expressways to the north of Jefferson City, which are at-grade expressways with a 70 MPH speed limit)
- Interstates, freeways, and expressways in urban areas: 60 MPH
- Other numbered state-maintained rural highways: 60 MPH
- State lettered highways: 55 MPH
Freeways are defined as: "a limited access divided highway of at least ten miles in length with four or more lanes which is not part of the federal interstate system of highways which does not have any crossovers or accesses from streets, roads or other highways at the same grade level as such divided highway within such ten miles of divided highway."
Expressways are defined as: "a divided highway of at least ten miles in length with four or more lanes which is not part of the federal interstate system of highways which has crossovers or accesses from streets, roads or other highways at the same grade level as such divided highway."
Urban Areas are defined as: "an area of fifty thousand population at a density at or greater than one thousand persons per square mile."
The highways and transportation commission may raise or lower the speed limit on these highways, however no speed limit may be set above 70 MPH on a numbered highway and 60 MPH on a lettered highway.
Interstate highways have minimum speed limits of 40 MPH.
Variable Speed Limits
Missouri concluded a two-year experiment with variable speed limits along I-270 around St. Louis. Digital signs had been erected along the freeway as well as additional signs alerting drivers about the use of variable speed limits. The limits will vary between 40 and 60 miles per hour, depending on traffic conditions, and could change by up to 5 mph every 5 minutes. These speed limits, as of January 2012, are now posted as "Advisory Speed Limits".
During the closure and major rebuild of I-64 in St. Louis, an additional lane was added to I-44 and I-70, and the speed limit was thus reduced to 55MPH on those roads within the St. Louis County and City. The I-64 construction has been completed, and the extra lanes were removed in 2010. In October 2010, the speed limit was restored to 60 MPH on both I-44 and I-70.
Exceptions to the statutory limits
Most two-lane roads with shoulders have a 60 MPH speed limit in Missouri. Two-lane roads without shoulders are usually, but not always, limited to 55 MPH. However, the following two-lane highways have a 65 MPH speed limit when bypassing or outside of incorporated areas.
- US-54 from El Dorado Springs west to the Kansas state line; from the MO-73 intersection southwest of Macks Creek to just west of the Niangua River bridge; and also along the Mexico bypass.
- US-63 from Vienna south to Thayer, near the Arkansas state line. Some of this route has three lanes, with the passing lane alternating between northbound and southbound traffic.
- MO-43 from US-54 south to Joplin
- MO-72 from Rolla south to Salem was raised from 60 MPH to 65 MPH by MODOT in the summer of 2013.
- MO-96 from I-44 west to Carthage
Most rural expressways have a 65 MPH speed limit, but the following have a 70 MPH speed limit.
- US-54 from the south end of the Mexico bypass to the Route W interchange just across the Missouri River from Jefferson City, with the exception of the I-70 interchange area at Kingdom City, which is 45 MPH. US-54 also has a 70 MPH speed limit from Fall Hill Road in Cole County to just north of the Business Route 54 intersection in Lake Ozark.
- US-63 from the south end of the Kirksville bypass to US-54 north of Jefferson City, with the exception of the section through Columbia from Route B to Route AC which is 65 MPH.
- MO-7 from I-49 to just west of Clinton.
- The US-71 expressway from Carthage to Harrisonville had a 70 MPH limit before it was upgraded to I-49.
Most Missouri lettered highways are 55 MPH, and in densely populated areas they can be less. There are a couple that have a speed limit of 60 MPH, though.
- Route M in Jefferson County is an expressway for most of its length, and most of the highway has a speed limit of 60 MPH.
- Route A in Jefferson County, an upgraded two lane road with shoulders, has a 60 MPH speed limit. Route A travels between Hillsboro and Festus.
In the urban areas of: St. Louis, Kansas City, Columbia, St. Joseph, and Springfield, the speed limit typically drops to 60 MPH on Interstates and freeways. In addition, on I-44 in Rolla the speed limit is reduced to 60 MPH from just west of Exit 184 to Exit 186 because of a substandard design.
Freeway speed limits in urban areas can be as low as 45 or 50 MPH in a few very short sections in downtown Kansas City and St. Louis, or as high as 65 MPH in the outer portions of the St. Louis, Kansas City and St. Joseph areas. The Cape Girardeau and Joplin areas have no reduced freeway speed limits, and I-435 inside the city limits of Kansas City maintains a 70 MPH limit from I-35 to I-29 around the northern part of the metro area.
I-29 in Kansas City has a limit of 70 MPH north of Barry Road in Platte County to south of Highway 169 in Buchanan County where the limit drops to 65 MPH. North of Frederick Road in Buchanan County the limit returns to 70 MPH until the Iowa state line.
Reasonable and prudent
In the years before 1974's national 55 mph limit, and for three years after the 1995 repeal of the increased 65 mph limit, Montana had a non-numeric "reasonable and prudent" speed limit during the daytime on most rural roads. Montana Code Annotated (MCA) Section 61-8-303 said "A person ... shall drive the vehicle ... at a rate of speed no greater than is reasonable and proper under the conditions existing at the point of operation ... so as not to unduly or unreasonably endanger the life, limb, property, or other rights of a person entitled to the use of the street or highway."
Montana law also specified a few numeric limits: a night speed limit, usually 55 or 65 mph (89–105 km/h), depending on road type; 25 mph (40 km/h) in urban districts and 35 mph (56 km/h) in construction zones.
The phrase "reasonable and prudent" is found in the language of most state speed laws. This allows prosecution under non-ideal conditions such as rain or snow when the speed limit would be imprudently fast.
No speed limit
On March 10, 1996, a Montana patrolman issued a speeding ticket to a driver traveling at 85 mph (136 km/h) on a stretch of State Highway 200. The 50 year-old driver (Rudy Stanko) was operating a 1996 Chevrolet Camaro with less than 10,000 miles (16,093 km) on the odometer. Although the officer gave no opinion as to what would have been a reasonable speed, the driver was convicted. The driver appealed to the Montana Supreme Court. The Court reversed the conviction in case No. 97-486 on December 23, 1998; it held that a law requiring drivers to drive at a non-numerical "reasonable and proper" speed "is so vague that it violates the Due Process Clause ... of the Montana Constitution".
- Montana's US, State, and even Secondary roads have speed limits posted similar to Texas — 70 mph/night:65; truck:60/night:55 (similar to the truck speed limit for secondary (Farm to Market) roads in Texas.)
75 mph speed limit
Despite this reversal, Montana's then-governor, Marc Racicot, did not convene an emergency session of the legislature. Montana technically had no speed limit whatsoever until June 1999, after the Montana legislature met in regular session and enacted a new law. The law's practical effect was to require numeric speed limits on all roads and disallow any speed limit higher than 75 mph (121 km/h).
Montana law still contains a section that says "a person shall operate a vehicle in a careful and prudent manner and at a reduced rate of speed no greater than is reasonable and prudent under the conditions existing at the point of operation, taking into account the amount and character of traffic, visibility, weather, and roadway conditions." However, this is a standard clause that appears in other state traffic codes and has the practical effect of requiring a speed lower than the speed limit where a lower speed is necessary to maintain a reasonable and prudent road manner.
Montana also has limited sections of night speed limits. Other speed limits in Montana are 25 mph in a school zone, 30 mph in a residential district, 35-45 mph on boulevards, 55 mph on traffic-light highways, 65-70 mph on rural divided 4-lane highways, and 55-70 mph on 2-lane undivided highways.
The maximum speed limit in Nebraska is 75 mph on rural Interstate highways. This speed limit only applies to Interstate 80 between Omaha and Lincoln, west of Lincoln to the Wyoming state line, and the small section of Interstate 76 which enters the southwestern corner of the state from Colorado to join I-80. The speed limit in rural areas of Nebraska is 65 unless otherwise posted.
The maximum speed limits in Nevada is 70–75 mph on rural freeways, 65–75 mph on other rural divided highways, 55–70 mph on primary two-lane roads, and 65 mph on urban freeways.
- I-15 is posted 70 mph south of Las Vegas to match California's 70 mph posted limit.
- US 95 north of Las Vegas is 70 mph.
- US 95 from south of US 93 near Boulder City south to Nevada Highway 163 is 75 mph.
- I-15 northeast of Las Vegas to Arizona is 75 mph.
- I-80 from Reno to Utah, varies 65–75 mph.
- US 50 Lake Tahoe to Ely and Utah is 65 mph.
- I-580 Exit 44 - Exit 50 is 70 mph; then, it's 65 mph.
- US 95 through downtown Las Vegas is 65 mph.
Prior to the imposition of the 50/55 MPH speed limit in late 1973, Nevada also had a "reasonable and proper" speed Limit (non-numeral) on most of its rural highways; both freeway and others. The speed limit on certain two lane highways is 70 mph including US 95 to the Oregon border (where the speed limit lowers to 55) and on certain sections of US 6 and 50 as they cross the Nevada desert. Speed limits are 15 to 25 mph in a school zone and 25 to 30 mph in a residential district.
The highest speed limit in New Hampshire is 70 mph (112 km/h). It can be found on Interstate 93 from mile marker 45 to the Vermont border. The minimum speed on Interstate Highways in New Hampshire is 45 mph where posted.
Provided that no hazard exists that requires lower speed, the speed of any vehicle not in excess of the limit is deemed to be prima facie lawful. The limit for "rural residential districts" and Class V highways outside the city or town compact is 35 mph. The limit for any "business or urban residence district" is 30 mph. School zones receive a 10 mph reduction in the limit 45 minutes before and after the beginning and end of a school day. The speed limit for a road work or construction area is 10 mph lower than the normal speed limit, but not more than 45 mph, when work is in progress. The speed limit for all other locations is 55 mph. The minimum limit that a speed can be set in a rural or urban district is 25 mph.
The speed limit on Interstate 93 through Franconia Notch State Park falls to 45 mph where the highway narrows to one lane in each direction, but rises back to 70 mph (in 10 mph increments going south) once the highway leaves Franconia Notch. Interstate 393 in Concord has a 55 mph posted speed limit for its entire length, with the exception of 45 mph and 35 mph zones on the westbound portion closest to the city center and the end of the highway. The Interstate 293 speed limit through downtown Manchester falls to 50 mph as it runs along the Merrimack River, but increases to 55 mph on either side of the city center.
HB146, which raises the speed limit on Interstate 93 from mile marker 45 to the Vermont border to 70 mph, passed both houses. The speed limit on Interstate 93 from mile marker 45 to the Vermont border increased to 70 mph on January 1, 2014.
New Jersey's only statutory speed limits is 50 mph rural, 25 mph urban. Since the state is largely suburbanized, it ranges between 25–50 mph depending the jurisdiction of the road and whether the municipality is township, village, borough or city status.
The common limited access freeway speed limit is 65 mph. However, shorter length freeways such as US 202, Route 15, and Route 33 remain at 55 mph. In all 65 mph speed zones, the speeding fines and "other violations" are doubled. This was the condition set for higher speed limits in New Jersey back in the late 1990s. Urban freeway speed limits are 50 to 55 mph. However, some freeways in urban areas retain a 65 mph speed limit such as the New Jersey Turnpike up to Exit 13 (Interstate 278), I-80 from the Delaware Water Gap (Exit 4) to the Passaic River (Exit 53) and I-78 from the Delaware River to the Newark border (Exit 55). Only the New Jersey Turnpike has variable speed limits on its entire length.
Four lane or greater state highways (often with a jersey divider or grass median) are generally posted at 55 mph (Such as Route 73 from CR 544 in Evesham Township to the Atlantic City Expressway). County four-lane highways and municipal maintained four-lane roads (with a jersey divider or grass median) are not posted above 50 mph.
Two-lane rural state highways and county maintained roads generally have 40 to 50 mph limits. The only two lane surface roads posted at 55 mph in New Jersey are County Route 539, Route 70, and Route 72 in the Pine Barrens of Ocean and Burlington Counties and Route 54 in Atlantic County. The Route 33 Freehold Bypass section where it is a super two freeway is also 55 mph.
Urban two lane roads in boroughs and cities are 25 or 30 mph. Residential streets at the municipal or county level are generally posted at 25 mph speed limits in boroughs and cities. However, they can be as high as 35 to 40 mph at the county level, less likely in municipal maintained roads. Municipal and county maintained roads through Townships are a bit more common with speed limits higher than 25 mph through residential areas. Generally, anything above 40 mph becomes uncommon. However, there are a handful of 45 mph residential stretches such as Terill Road in Scotch Plains and Woodbridge Avenue (CR 514) in Edison. At 50 mph, County Route 537 in Freehold Township (south of Route 18) and Half Acre Road in Monroe.
School zones through urban and suburban areas on two lane roadways are normally posted with one sign and often without prior warning. Also, it is not unusual to see "25 mph when children are present" signs regardless of the road's default speed limit (Example would be going from 45 mph to 25 mph).
With the exception of wartime, New Mexico had no default numeric speed limit until the early 1950s. Prior to the national 55 mph limit in 1974, the speed limit on rural Interstates was 75 miles per hour during the day and 70 mph at night. Primary highways in open areas had daytime speed limits of 70 mph and nighttime ones of 60 mph. Secondary highways in open areas had daytime speed limits of 60 mph and nighttime ones of 50 mph. Before the end of federal speed controls, the maximum speed limit was 65 mph on Interstate routes and 55 mph elsewhere. In May 1996 legislation enacted by Governor Gary Johnson raised the absolute speed limit in New Mexico to 75 mph. Signs are posted on the vast majority of the mileage of Interstate routes to that effect.
New Mexico has six major freeway facilities which include three lengthy Interstate routes. Part of US-70 (as a divided highway) between Las Cruces and Alamogordo is the only section of non-Interstate route as well as being the only road in New Mexico that's not a freeway to have the 75 mph limit; New Mexico, Nevada (US 95 south of US 93) and Texas are the only three states with 75 mph limits on roads that aren't freeways. There is no statutory requirement for reduced speeds on urban freeways so that, for example at Santa Fe and Las Vegas the speed limit remains 75 mph on I-25. Nonetheless, there are 65 mph limits on freeways in more heavily urbanized areas such as Albuquerque and Las Cruces. Other reduced speed limits do exist, but the lowest speed limit under normal conditions on New Mexico's freeways is 55 mph. The only 55 mph zone on New Mexico's interstate highways is a short stretch of I-25 between the Big I and Gibson Boulevard in Albuquerque, as this particular stretch of freeway has closely spaced interchanges and sharp curves.
By statute, other state maintained roads may have speed limits of up to 75 mph.  Four-lane divided highways in open areas often have 65 mph limits, with some 70 mph limits, such as almost the entire length of US 550 from Bloomfield to Bernalillo. There is a trend toward posting a 70 mph limit on these highways, such as the recent 70 mph speed limit posting (increased from 65 mph) on a 23-mile stretch of U.S. 70 west of Roswell.
Primary two-lane highways in open areas with parking shoulders often have 65 mph limits.
Most primary two-lane highways without parking shoulders in open and mixed rural areas still have a 55 mph limit, but some have 60 mph limits.
A 65 mph left lane minimum speed limit is sometimes indicated on 75 mph roads with steep grades, "slower traffic keep right" is also in effect. On one-way roadways state law reserves the left and center lanes of two or more lanes for passing. There are reduced advisory speed limits for some roads during poor weather. Speeding fines are doubled in construction zones and designated safety corridors, with signs often stating this. There are no longer night speed limits, nor are there any differential speed limits for heavy trucks.
There are two other statutory speed limits in New Mexico which are often altered, especially on urban arterials or even city or countywide: thirty miles per hour in a "business or residence district" and fifteen miles per hour near schools at certain times. For example, in Albuquerque the default speed limit is thirty miles per hour as per state law, but many streets have a different speed limit. Some school zones there have twenty mile per hour speed limits. The city of Santa Fe's default speed limit is twenty five miles per hour. Although there are no signs to make drivers aware of the altered limit, the limit is signed on most roads where it applies. Los Alamos County alters the urban default and absolute speed limits to twenty five miles per hour and 50 mph respectively, but posts signs at county lines.
- The speed limit on NM 502 between San Ildefonso Pueblo and Pojoaque Valley High School had a 65-mph speed limit. In November 2005, the stretch between NM-4 and Pojoaque became a safety corridor. In 2007, the speed limit on the San Ildefonso-Pojoaque stretch was lowered to 55 mph.
- On Highway 68, the speed limit is 60 mph on much of the four-lane stretch between Española and Velarde.
- Minimum 65 left lane signs are posted on I-40 west of Albuquerque, a night speed limit of 30 mph is posted on State Highway 7 west of White's City going into Carlsbad Caverns.
- Truck speed limit signs are rarely posted. One road has a posted limit of 45 mph/trucks:35 in Escondida, just north of Socorro, and US 82 east of Alamogordo has a posted limit of 55 mph/trucks:50 for approximately a two-mile stretch.
- As of December 24, 2009, US 54 still has a 55 mph speed limit north of Tularosa. Yet NM-9 and CR-A003 have a 65 mph speed limit east of Columbus to NM 136 near Santa Teresa. CR-A003 (Columbus-Santa Teresa Highway) is the only county road in New Mexico to exceed the statutory maximum 55 mph speed limit for county roads.
- Interstate 10 was 70 mph between the Texas-New Mexico state line and two miles south of I-25 in Las Cruces until October 2012, when it was raised to 75 mph. While it is 75 mph in the rest of New Mexico, the speed limit is 65 mph in Las Cruces, Deming, and Lordsburg. I-25 was posted 70 mph in Sandoval County from the Bernalillo-Sandoval county line to US 550, but the limit was raised to 75 mph in May 2014.
- State Highway 30, a paved two-lane road with shoulders, has a 55 mph speed limit from NM 502 to the junction with the road for Santa Clara Pueblo, then reduces to 45 mph and then to 40 mph upon entering the Española city limits. Prior to 2008 the speed limits were 60 mph from NM 502 until the junction with the road for Santa Clara Pueblo where it reduced to 45 mph, raised back to 60 mph until the Española city limits where it reduced to 50 mph, and then to 40 mph near its northern terminus at US 84/285.
- The posted speed limit on Silver Avenue in Albuquerque is 18 MPH. When the route was designated as a bicycle route in the late 2000s, Albuquerque officials established the unusual 18 MPH speed limit on Silver Avenue to increase motorists' awareness of the street's designation as a city bicycle route.
Outside of Bernalillo County, no points are assessed to one's license for speeding in rural areas in New Mexico, unless the excessive speed was a contributing factor to a traffic accident.
Speed limits are statutory (set by law) or regulatory (enacted by regulation), not necessarily by engineering standards. New York has a blanket statutory "Reasonable and Prudent" speed law.
The highest posted speed limit in New York is 65 mph (105 km/h), found only on limited-access freeways (including some state highways, most of the New York State Thruway and select Interstate Highways). The default speed limit, posted as the "State Speed Limit", is 55 MPH, which is in effect unless otherwise posted or in the absence of speed limit signs.
The New York State Department of Transportation sets speed limits in the vast majority of the state. Counties and most towns must petition DOT to change a speed limit. State law allows villages, cities, towns with more than 50,000 residents, and certain towns defined by law to be "suburban" to set speed limits on state, county, and local roads within their borders.
There is no state law regarding minimum speed limits, but minimum speed limit of 40 mph has been set on the entire length of Interstate 787 and the entire length of Interstate 495 (the Long Island Expressway). The New York State Thruway does not have a firm minimum speed, but there are signs advising drivers to use their flashers when traveling at speeds below 40 mph.
While New York does not have truck speed restrictions per se, the New England Thruway (Interstate 95) features "State Speed Limit 55" signs right next to "Truck Speed Limit 50" signs.
New York law allows area speed limits. An area speed limit applies to all highways within a specified area, except those specifically excluded. The area may be an entire municipality, or only a specific neighborhood. The defined area may also be the grounds of a school, hospital, or other institution. Area speed limits are signed at their perimeters with signs reading "Area Speed Limit" and the speed limit value shown below. "Area" may be replaced with a term that more precisely defines the area boundaries, such as "Town," "City," "Park," or "Campus".
Normally, the end of a lowered speed limit is marked with a sign reading "State Speed Limit 55", indicating that the statewide speed limit applies. In areas where a curve or other road condition makes the state speed limit inadvisable, a sign reading "End XX m.p.h. Limit" may be used, with XX replaced with the speed limit value. A "State Speed Limit 55" sign should be installed after the curve. This sign is sometimes misused in locations where the speed limit changes to a speed other than 55 mph.
Excepting school zones, state law prohibits speed limits below 25 mph. School speed limits may be set as low as 15 mph. New York City has established a number of 20 mph "Neighborhood Slow Zones" in residential neighborhoods.
New York's Criminal Procedure Law prevents law enforcement personnel from issuing a ticket for any offense that they did not witness personally, meaning that, among other ramifications, the state's electronic toll collection system can not be used for speed enforcement.
Many expressways and parkways in the New York City suburbs were posted as high as 65 mph. During the 1973 Oil Embargo, New York lowered its speed limit to 50. The National Maximum Speed Law brought statewide speed limits up to 55. The city of New York, being a city, retained the 50 mph speed limit. New York did not take advantage of the 1987 Congressional provision allowing 65 mph zones on rural freeways, instead waiting until NMSL's repeal in late 1995.
Until September 2003, the state legislature needed to approve individual 65 mph zones, a lengthy process taking months or years of politically motivated debate. Then-Governor George Pataki signed legislation in September 2003 that enables NYSDOT and New York State Thruway Authority to raise speed limits to 65 mph on its roads that meet established design and safety standards. This legislation became active in March 2004, and was the reason for the 65 zones on NY Route 7 (locally known as "Alternate Route 7") and Interstate 84.
Along two-lane rural primary and secondary roads outside municipal limits in North Carolina, the statutory speed limit is 55 mph unless otherwise posted. Prior to the National Maximum Speed Law that went into effect nationwide, North Carolina used to have 60 mph speed limits on two-lane primary and secondary roads. Inside the municipal limits, the statutory speed limit is 35 mph unless otherwise posted. The downtown statutory speed limit is 20 mph unless otherwise posted. "Reduce Speed Ahead" (RSA) signage is the norm whenever the speed limit drops at any level. Note that the NC DOT uses the imperative verb "reduce" instead of the adjectival form "reduced" that is standard in other states, although some municipalities now use "reduced" in their signs. In addition, a speed limit drop of 15 mph or greater normally includes a second warning sign after the RSA. For example in a 55 mph zone, a sign prior to the RSA sign would say "BEGIN 35 1000 FEET AHEAD" and then the 35 mph posted speed limit. Three to eight lane boulevards with or without center turn lanes, range from 35 mph to 50 mph within municipal limits statewide.
It is rare that NCDOT will assign a speed drop greater than 20 mph. In Bertie County, the US 17 bypass in Windsor drops from 70 mph to 45 mph. In Moore County, Shady Lane Road outside of Carthage in the Hillcrest community drops from 55 mph to 30 mph.
School zone speed limits generally entail a 10 to 20 mph reduction below the original speed limit during times of day used for school arrivals and departures. Such a speed limit would be indicated when entering the school zone. Also, the default or modified speed limit is indicated after leaving the school zone. A school zone speed limit cannot be less than 20 mph.
Military bases are generally posted at a maximum of 50 mph. As of May 2010, Fort Bragg military two-lane roadways are now posted at 55 mph instead of 50 mph. Prior to May 2010, the speed limits higher than 50 mph through military bases were only on N.C. Highway 690 along the north side of Fort Bragg, Murchison Road (also known as N.C. Highway 210) and the All American Freeway (which is classified and numbered as a state-maintained secondary road even though it is a freeway).
The state park speed limit is 25 mph unless otherwise posted. These are not limited to places such as Hanging Rock State Park and Mount Mitchell State Park. The Blue Ridge Parkway is 45 mph. However, there are occasional 35 mph stretches. The National Park Service is responsible for highway maintenance and speed enforcement.
The county governments of North Carolina do not have any control over speed limits or any other aspect of road operation, as there are no county roads in the state. Municipalities, on the other hand, can set speed limits on city-controlled roadways, subject to applicable state laws. Freeways and expressways with no primary route number are part of the state secondary road system and bear route numbers of 1000 or greater. Their maximum posted speed limit is 55 mph with four exceptions.
A speed limit of 70 mph is relatively uncommon in much of metropolitan North Carolina, though it applies to many rural interstate highways in the state, as well as several non-interstate freeways. The following are the only roads with 70 mph limits:
- Interstate 40 from Old Fort to Morganton, from Statesville to Clemmons, and from Clayton to Wilmington
- Interstate 77 north of Statesville
- Interstate 85 from Lexington to High Point and through Granville County (as of June 2013).
- Interstate 95 from the SC state line to Exit 10 (Chicken Road), along the Fayetteville Bypass and north of Kenly to the VA state line.
- Interstate 140 on the Wilmington bypass
- Interstate 540 from U.S. 70 near Brier Creek to the U.S. 64/264 interchange near Knightdale.
- Interstate 795 from Goldsboro to Wilson
- US Highway 1 from the southern end of the Sanford Bypass to NC 55 in Apex.
- US Highway 17 on the Elizabeth City and Windsor bypasses.
- US Highway 64 from Interstate 440 to Williamston (except on the Rocky Mount bypass) and from Plymouth to Columbia
- US Highway 70 on the Clayton bypass, and from Dover to New Bern
- US Highway 74 / Future Interstate 74 on the Rockingham-Hamlet Bypass and from Chadbourn to Whiteville, as well as a section from NC 108 east of I-26 in Polk County to mile 187 in Rutherford County.
- US Highway 264 from Wendell to Greenville
These lengths make up approximately 589 miles, or 27%, of the total freeway mileage in North Carolina (405 miles or 31% of the state's growing Interstate system). Four-lane freeway-grade highways are generally posted at 65 mph through the state of North Carolina.
60 mph speed limits
Interstate freeways with 60 mph speed limits are found along on I-26 between Asheville and Hendersonville and north of Asheville to Tennessee; I-40 between Asheville and Waynesville and through Greensboro; on I-85 in Gaston (east of US 321 to the Mecklenburg County line) and Mecklenburg counties and through Durham; on I-440 along the northern half of Raleigh's Beltline
Non-Interstate Freeways (US Highways) with 60 mph speed limits are found along on the US 1 Henderson Bypass (as of December 2011); US-23 Waynesville Bypass; US 64 over the Virginia Dare Memorial Bridge between Manns Harbor and Manteo; US 74 Laurinburg bypass and in Brunswick County from the Leland Industrial Park to NC 133; US 301/Business 95 between Fayetteville and Eastover; the US-311 High Point Bypass and the US-401 Fayetteville bypass.
Only two State Secondary Road freeways in the state that has a 60 mph speed limit are the Wade Avenue Extension as of February 2012 and Aviation Parkway (from south of Globe Rd to Airport Blvd) as of July 2014 which are both in Raleigh.
60 mph speed limits along non-freeway segments are growing in popularity and have replaced 55 mph limits on several boulevard and expressway segments throughout the state. The boulevard speed limit changes go against the NCDOT rationale behind signing 60 mph speed limits along only freeway and expressway segments. As of June 1, 2008, some examples of the affected boulevards are US 17 north of Elizabeth City, US 74 east of Wadesboro and NC 11 in Pitt County.
60 mph speed limits along Expressways are US 1 in northeastern Moore County, US 17 on bypass routes in Brunswick County, US 74 east of I-95, US 117 in Wayne County & Duplin County, US 220 in Rockingham County only along bypass segments and on NC 16 in Lincoln and Catawba counties (as of October 2012). Previously, the entire US 220 alignment from NC 68 to the Virginia state line was 60 mph but went back to 55 mph between NC 68 and NC 704.
Three State Secondary road expressways in the state that has a 60 mph speed limit are the US 117 Connector in Sampson and Duplin Counties between US 117 and I-40 (The designation in Sampson County leaving I-40 towards Duplin County is SR 1783/Connector Road) and the un-numbered connector northwest of Kinston serving the Global Transpark.
There is a default minimum speed limit on Interstate and primary highways only when signs are present. The minimum is 40 mph if the maximum is 55 mph. The minimum is 45 mph if the maximum is at least 60 mph. These minimums do not apply to vehicles that are towing other vehicles.
North Carolina as well as other states operates a Safe Driving Incentive Plan (SDIP), a program that leads to insurance surcharges for moving violations based on a point system. In general, for speeding violations less than 10 mph over the posted speed limit in a speed zone less than 55 mph, one point is assessed; two points are assessed for exceeding 10 mph over the limit or speeding in a zone with a speed limit of greater than 55 mph.
A driver's licence will be suspended for travelling faster than 15 mph over the speed limit, provided the speed travelled is at least 55 mph; suspensions can result for other speeding infractions, such as travelling faster than 75 mph in a 65 mph or less zone or faster than 80 mph in a 70 mph zone.
The highest speed limit found in North Dakota is 75 mph, which can be found on Interstates 29 and 94. Urban speed limits are as follows: Fargo: 55 mph, (Except for the stretch on Interstate 29 between 32nd and 52nd Ave S which is still posted at 75 mph) Bismarck/Mandan 60 mph on I-94 in North Dakota and Bismarck Expressway is at 40–55 MPH, Grand Forks, Valley City, Jamestown, Fargo on Interstate 29 between 32nd and 52nd Ave S, and Dickinson remain at 75 mph. Rural four-lane highways are 70 mph includes the four highways that are post at limit. Most of US2 north of Williston between Grand Forks, Most of US83 South of Minot AFB to Bismarck, US52/US281 Buchanan between Jamestown, and ND13 between East of I-29 to West of Wahpeton. Rural 2-Lane US numbered, and State Highways have 45–65 mph limits. Divided US numbered, and State Highways that pass through cities have 25–55 mph limits. undivided US numbered, and State Highways that pass through cities have 25–50 mph limits. 40–65 mph speed limits on paved county roads and BIA roads for cars and 30–65 mph for trucks. 40–55 mph speed limits on unpaved county roads and BIA roads for cars and 30–55 mph for trucks. Speed limits on surface streets range from 30 to 40 mph. Residential streets are generally 10–25 mph. School zones are 15–25 mph. It is to uncommon see residential and business districts above 50 MPH.
- US 2 through Minot has a 50 MPH limit that increases to 55 MPH before the Ward County Road 19, US 52 and US 52 Bus. interchange.
- US 2 through Surrey has a 60 MPH limit.
- US 83 through Minot between 27th Avenue Northwest and Ward County Road 10 East has a 55 MPH limit.
- US 52 through Bergen, Voltarie, Sawyer, Between 20th avenue and county highway 19 through Minot has a 65 MPH limit. Fessenden, Harvey, Balfour, and Drake have a 55 MPH limit.
- US 52/ND 200 through Sykeston and through Carrington between 65th Aveune Northeast and Red River Valley and Western Railroad crossing has 65 MPH Limit.
- US 52/US 281 through Meville and Edmonds has a 65 MPH limit.
- ND 1 through Rogers and Walum has a 65 MPH limit.
- ND 14 through Upham, Wing, and Kramer has a 65 MPH limit.
- ND 18 through Leonard and Blanchard has a 65 MPH limit.
- ND 36 through Wing has a 65 MPH limit.
- ND 65 through Jessie has a 65 MPH limit.
- Portions of US 2 through Leeds, Lakota, Michigan, and Petersburg has a 70 MPH speed limit in residential and business areas.
The maximum speed limit found on highways in Ohio is a uniform limit of 70 miles per hour (110 km/h) on the Ohio Turnpike and rural freeways. The speed limit is 65 miles per hour (105 km/h) on other divided highways. No non-divided highway in the state currently has a speed limit higher than 55 miles per hour (89 km/h), though ODOT is now permitted to increase undivided roads to 60 miles per hour (97 km/h) . Ohio's original speed limit was 70 mph (113 km/h) in 1963, lowered to 55 mph during oil crisis until 1987, then raised to 65 mph until 1 July 2013 when the state's two-year transportation budget was passed by Governor John Kasich and 70 mph signs were posted.
Ohio now has a separate urban speed limit of 65 miles per hour (105 km/h) on Interstates by state law, yet many urban areas have lower speed limits due to safety concerns found in speed studies. These commonly are in the 50–60 mph range. For instance, in most of metro Dayton and Cincinnati, as well as in downtown Columbus, the speed limit is 55 miles per hour (89 km/h), while in Cleveland, Toledo, and Akron the speed limit is 60 miles per hour (97 km/h); however, in central Cleveland along the Inner Belt, the speed limit is 50 miles per hour (80 km/h). Some urban areas are also posted with minimum speed limits, usually with a minimum of 40 or 45. At one time, portions of Interstate 76 and Interstate 77 in downtown Akron had a maximum speed limit of 50 mph and a minimum speed limit of 35 mph.
On Sept. 29, 2013, Ohio eliminated the 55 miles per hour (89 km/h) truck limit on most remaining divided highways. Previously, only trucks travelling the Interstates and Ohio Turnpike posted at 65 mph or higher were permitted to travel the same speed as passenger vehicles.
70 mph speed limit
On December 20, 2010, the Ohio Turnpike Commission voted to increase the speed limit of the Ohio Turnpike to 70 miles per hour (110 km/h). Despite opposition from the Ohio Trucking Association and the Ohio Motorists Association, the increase was approved by the Commission by a vote of 4 to 1 and went into effect on April 1, 2011.
Bills were introduced in the state 2011, and 2013 that would have restored rural freeway speed limits to 70 mph. Much of the content of the latter was included in the state's 2013 two-year transportation budget, which was signed into law on April 1, 2013, effective the new budget year which started July 1, 2013. Speed limits on some 2 lane highways were eligible for an increase to 60 mph, but none were increased by the Department of Transportation. ODOT has performed studies on rural freeways and expressways, and announced speed limit increases on more than 600 miles of roadway. 398 mi of rural freeways will increase to 70 miles per hour (110 km/h), and 194 mi of rural divided highway will increase to 60 miles per hour (97 km/h). Split speed limits are eliminated with this increase.
In Oklahoma, the maximum speed limit is 75 miles per hour on turnpikes and 70 mph on all other freeways. Most other rural highways have a 65 mph speed limit (although some rural divided highways have a 70 mph limit). Minimum speed limits are 25 mph below the maximum speed limit on more or less all Interstate Highways. For example, on the turnpikes, which have a maximum speed limit of 75 mph, maximum speed-limit signs are nearly always accompanied by a sign stating a minimum speed limit of 50 mph. Where turnpikes are signed with a speed limit of 75 miles per hour, a sign warning "no tolerance" is posted, warning drivers that state troopers will write tickets for speeding for ANY violation of this higher limit.
The highest posted speed limit in Oregon is 65 mph on rural freeways. Oregon state statutes allow for a maximum speed limit of 70 mph on rural interstate highways, and the law gives the Oregon Department of Transportation (ODOT) discretion to define which freeway segments to post the 70 mph speed limit. However, as of 2013, ODOT has not raised speed limits beyond the current 65 mph.
Although the speed limit can be raised to 70 mph based on engineering studies, ODOT has not identified any freeway sections that it believes should be raised beyond the 65 mph limit. In 2004, ODOT had released an engineering study on the average and 85th percentile speeds on interstate highways. This study found that the 85th percentile speed on rural interstates by passenger cars was 71.1 mph with a statewide average of 66.3 mph. The engineering study recommended raising the speed limit on rural interstates to 70 mph. Despite this, ODOT refused to post the 70 mph limit due to safety concerns and its associated monetary costs; however, there appears to be no higher fatality levels in other states when the limit was raised. In all rural areas in Oregon, the speed limit is 55 unless otherwise posted.
Up until 2002, Oregon state law required that all speed limit signs omit the word limit from their display. The reasoning behind this was related to the explicit "basic speed" law that existed, which allowed citation for exceeding speeds "too fast for conditions" regardless of the posted speed. The spacing between and appearance of the numbers on the signs vary greatly depending on which jurisdiction made the sign. In 2002, the Oregon Department of Transportation required the inclusion of the word "limit" on speed signs on interstate highways (though the older "Speed" signs are still up in many locations), and left it up to local government agencies to decide on whether "limit"-branded signs would be installed on other roads. Most have chosen not to change over with a few exceptions to the rule. Speed Limit 60 signs can be found on Interstate 5 through Salem, on Interstate 84 through east Portland, 55 signs can be found on Interstate 205, and some new 50 signs are found on Interstate 405. The city of Beaverton has been the most liberal in retrofitting the standard-form Speed Limit sign. Whenever a "Speed" sign is damaged or vandalized in Beaverton city limits, a "Speed Limit" sign takes its place.
Attempts to raise speed limits
Throughout the late 1990s the Oregon state legislature passed multiple bills that would have raised the speed limit to 75 miles per hour on rural Interstate Highways and up to 70 mph on certain rural two-lane highways in the eastern portions of the state. Each year Governor John Kitzhaber vetoed the bill due to safety concerns and he was worried that the 20 mph increase in car and truck speeds would raise road hazards. In 2003, the Oregon state legislature passed a bill that would have raised the maximum permissible speed limit on Interstate Highways to 70 mph for cars with a 5 mph differential for trucks, up from the previous 65 mph limit for cars with a 10 mph differential; this bill was signed into law by then newly elected Governor Ted Kulongoski on September 26, 2003. In 2004 the Oregon Department of Transportation decided to not implement the increase out of concerns that it would not be safe to have trucks traveling at 65 mph. Although ODOT's 2004 study revealed that it is safe for cars to be traveling at 70 mph and trucks at 60 mph, Oregon still remains the only state in the contiguous United States west of the Mississippi River to have a maximum state speed limit that is under 70 mph. Prior to the National Maximum Speed Law, the speed limit on Oregon freeways was 75 mph with some 70 limits on two-lane roads in eastern portions of the state.
School speed limits
In 2004, a law was passed revising Oregon's school speed limit laws. In school zones, on roads with speed limits of 30 mph or below, drivers were required to slow to 20 mph 24 hours a day, 365 days a year, regardless of whether or not children were present. This replaced most 'when children are present' placards. If the speed limit was 35 mph or higher, the school zone limit would be imposed either by flashing yellow lights or a placard denoting times and days of the week when the limit was in effect. The at-all-times rule was highly unpopular with motorists and was widely ignored. In 2006, the law was revised again, taking away the 'at all times' requirement and replacing it with a time-of-day system (usually school days, 7 a.m. to 5 pm). School crossings with flashing yellow lights remain. In many communities, school zones are strictly enforced and speed traps in these areas are commonly employed.
ODOT has not chosen a variation of speed between two-lane roads in Oregon, regardless of the terrain. Any rural two-lane road in the state has a default speed limit of 55 mph. Town speed limits are 15 mph in an alley, 20 mph in a school zone, 35 mph on boulevards, and 45 mph on roads with traffic lights.
In Pennsylvania the maximum freeway speed limit is generally 65 mph (105 km/h), with a select few sections of rural freeway and the Pennsylvania Turnpike signed at 70 mph (113 km/h). The speed limit on urban freeways ranges from a low of 50 mph in downtown Pittsburgh and Philadelphia to 65 mph in some areas.
In 1940, when the Pennsylvania Turnpike was opened between Irwin and Carlisle, the entire 160 mile limited-access toll road did not have a speed limit, similar to that of the German Autobahns. In 1941, a speed limit of 70 mph (113 km/h) was established, only to be reduced to 35 mph (56 km/h) during the war years (1942–45). After WWII, the limit was raised to 70 mph on the four-lane sections, with the two-lane tunnels having 50 mph (80 km/h) for cars and 40 mph (64 km/h) for trucks. Prior to the 1974 federal speed limit law, all Interstates and the Turnpike had a 65 mph (105 km/h) speed limit on rural stretches and 60 mph (97 km/h) speed limit in urban areas.
In 1995, the state raised the speed limit on rural stretches of Interstate Highways and the Pennsylvania Turnpike system to 65 mph (105 km/h), with urban areas having a 55 mph (89 km/h) limit. In 1997, PennDOT raised the speed limit to some rural non-Interstate Highway bypasses to 65 mph (105 km/h). In 2005, with the change in the designation of "urban zones" in the state, the entire lengths of both the Pennsylvania Turnpike's east–west mainline and Northeast Extension were given 65 mph (105 km/h) limits, except at the tunnels and through the very winding 5.5 mile (9 km) eastern approach to the Allegheny Mountain Tunnel.
The 70 mph speed limit was authorized by House Bill 1060, which was signed by Governor Tom Corbett on November 25, 2013. On July 18, 2014, the Pennsylvania Turnpike Commission announced the return of the 70 mph speed limit on a 97-mile stretch of the mainline from the Blue Mountain interchange (MP 201) to the Morgantown interchange (MP 298). Signs were erected on July 22, 2014. On July 23, 2014, PennDOT announced the speed limit will be increased to 70 mph on Interstate 80 between interchange 101 in DuBois, Clearfield County and milepost 189 in Clinton County and on Interstate 380 between interchange 3 near Mount Pocono, Monroe County and the junction with Interstate 84 in Lackawanna County, on or around August 11, 2014 as a pilot project. If the pilot project turns out well, the remainder of the Pennsylvania Turnpike system may see 70 mph limits.
On non-freeway roads, speed limits are generally held at 55 mph (89 km/h) for rural four-lane roads, 55 mph (89 km/h) for rural two-lane roads, 45–55 mph (72–89 km/h) for urban four lane roads and 40–45 (sometimes, but rarely, 50 mph) mph (64–72 km/h) for urban two lane roads, 35–45 mph for roads in commercial business areas, 30-35 mph (56 km/h) for major roads in residential areas, 20-25 mph (40 km/h) for most municipal residential streets, including main north–south and east–west roads in county seats and other mid-sized to large towns, and 15 mph (24 km/h) for school zones during school arrival and departure times only. It is also only in effect on days that the school the road goes near is in session. Many schools have signs that blink when the school speed limit is in effect. There is no reduced school speed on divided highways, even if the school sits right beside the highway.
All state-owned two-lane roads in rural areas within Pennsylvania have a default speed limit of 55 mph unless otherwise posted.
The Pennsylvania Turnpike has a minimum speed limit of 15 mph below the posted maximum speed, though the minimum is only sporadically posted. This is apparently not enforced in areas with steep grades as signs are posted which only instruct drivers to use their flashers if traveling below 50 mph (40 if the speed limit is 55). Pennsylvania has no default minimum speed limit on any other roads. However, minimum speed limits on certain highways may be enacted and posted as provided by Section 3364(c) of the Pennsylvania Motor Vehicle Code (Title 75 of the Pennsylvania Consolidated Statutes).
§3364(a) also requires, "Except when reduced speed is necessary for safe operation or in compliance with law, whenever any person drives a vehicle upon a roadway having width for not more than one lane of traffic in each direction at less than the maximum posted speed and at such a slow speed as to impede the normal and reasonable movement of traffic, the driver shall, at the first opportunity when and where it is reasonable and safe to do so and after giving appropriate signal, drive completely off the roadway and onto the berm or shoulder of the highway. The driver may return to the roadway after giving appropriate signal only when the movement can be made in safety and so as not to impede the normal and reasonable movement of traffic."
Drivers cannot be stopped by police for driving less than 6 mph over the posted speed limit (10 MPH if the speed limit is less than 55 MPH and non-radar timing devices are used, as use of radar devices is limited to "members of the Pennsylvania State Police" by §3368c2).
The US territory of Puerto Rico regulates and posts speed limits in miles per hour, although highway signage for distances are in kilometers. Tolled Autopistas can have speed limits up to 65 mph, while other expressways have speed limits up to 60 mph. The maximum statutory speed limit for any expressway may in theory be 65 mph. The rural default speed limit is 45 mph but may be increased to 55 mph. In residential areas, only multilane roads have limits up to 35 mph, other roads are restricted to a maximum speed of 25 mph. Only rural school zones have the higher 25 mph limit. Speed limits for "heavy motor vehicles", such as school buses, are always 10 mph lower than that allowed for lighter vehicles, except in urban school zones where the limit is 15 mph. Vehicles carrying hazardous materials are limited to 30 mph in rural areas and 15 mph in urban ones.
Along two-lane roadways, the default speed limit is 50 mph during the daytime outside a business or residential district. "Daytime" means a half-hour before sunset and a half-hour after sunrise. At night time and also uncommon on the East Coast, the default speed limit is 45 mph outside a business or residential district. Through the CBD and residential district, the default speed limit is 25 mph. Through school zones within 300 feet, the default speed limit is 20 mph. Local governments are barred from raising the default speed limits during the day and at night. Divided highways such as rural Interstates are generally posted at 65 mph but 55 mph closer to Providence. Divided arterials and expressways are posted no higher than 50 mph. This includes US 1 south of RI 4 to Westerly. A speed limit of 65 mph may be allowed on rural interstates based on engineering studies. Currently, however, the only interstates raised to 65 are Interstate 95 from exits 1 to exit 8 and Interstate 295.
Interstate speed limits in South Carolina are posted at 70 mph. Interstates passing through "Urban" areas are dropped to 60 mph. The urban area assignment of 60 mph usually includes the metropolitan area and the actual inner city area. The two exceptions to the rule are the SC 31 freeway around Myrtle Beach and I-95 around Florence. SC 31 is posted at 65 mph even though it is in the greater Myrtle Beach area. SC 31 was originally posted at 60 mph when it was built in 2004. I-95 even as a 6 lane semi-urban built freeway, maintains a 70 mph speed limit through the Florence area (as of June 2013, from just south of exit 160 to just south of exit 164, the speed limit has been reduced to 60 mph, a text-book speed trap). It is 6 lanes from SC 327 to I-20. It is one of five states (Pennsylvania and Delaware at 55 mph and New Hampshire at 65 mph (I-95 in NH drops to 55 mph about 2 miles south of the ME line)) from Maine to Florida in which I-95 retains one speed limit throughout the entire state.
Four-lane arterials by default are posted at 60 mph. Four-lane bypasses at 60 mph can be found in Marion and Sumter, but others remain at 55 mph. It is not uncommon that 55 mph can be expected in more built-up areas prior to municipalities and/or if the engineering on the highway is below standards.
Two-lane roads are 55 mph by default. However, a handful of counties maintained as either state secondary roads or county roads are posted at 45 mph.
Central business districts (CBDs) are posted at 30 mph. Unlike North Carolina with their default downtown speed limit of 20 mph, they are rare to find in South Carolina in downtown areas. A recent trend is occurring with CBD speed limits that they are being signed at 25 mph in random municipalities around the state.
Speed limit drops generally are done in 10 mph increments but 20 mph are not uncommon. Improvements in the mid-2000s were done by SCDOT to warn motorists ahead of time for speed drops on various roadways. However, there are still some roadways that have not received that treatment. However, there are a couple roadways that get 25 mph to 30 mph drops as well. The speed limit drops from 55 mph to 25 mph at a traffic circle with US 378 and SC 391 in eastern Saluda County. On US 52 northbound approaching Kingstree, the speed limit drops from 60 mph to 35 mph. On I-95 for the off-ramp at Exit 22 in Ridgeland drops from 70 mph to 40 mph.
Shortly after the December 1995 repeal of the 65/55 mph National Maximum Speed Law, South Dakota raised its general rural speed limits to 75 mph on freeways and 65 mph on other roads along with 70 on a few 4 lane highways. Almost a decade after posting the 75 mph limit, average speeds on South Dakotan rural freeways remain at or below the speed limit.
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Tennessee generally posts its rural interstates at 70 mph. These include all of the state's two-digit Interstates (except Interstate 55). Urban interstates are generally posted at 55 mph. Four-lane roadways regardless whether they are "controlled access" or not are posted as high as 65 mph but are generally found to be a 55 mph. These are often hotbeds for speed camera enforcement leading into a municipality. Two-lane state-maintained roads are generally but not always posted at 55 mph outside the municipal limits. In east Tennessee, most mountain roads leading to North Carolina are poorly posted at 45 mph. Furthermore, two-lane roads such as US 321 and TN 91 have the same mountain and road width characteristics when leaving Tennessee into North Carolina or Virginia at 55 mph.
Inside a municipality, speed limit assignments are often a mystery on state-maintained roads. This could range from 15–55 mph depending on the type of roadway. This is because the state of Tennessee grants strong home rule powers to municipalities and Dillon's Rule for unincorporated areas in the county for speed limit assignments. Unlike other states, this greatly weakens TennDOT's ability to sign predictable speed limits in a reasonable and prudent matter. Also, Tennessee has a high percentage of roadways maintained by the counties.
Several counties, including Anderson, Blount, Hamilton, Jefferson, Knox, Loudon, Sevier, Shelby, and Sullivan counties, have enacted environmental speed limits, affecting rural freeways. These restrictions cap speed limits at 65 mph (55 mph for trucks). Although the Nashville Metropolitan Area is the state's largest, Davidson County has yet to impose a similar speed limit. Since Nashville encompasses nearly all of the county, speeds are limited to 55 mph or 65 mph (with no separate truck restrictions) along most (but not all) of the county's freeways.
Prior to 1974, the maximum speed limit on Tennessee's Interstate highways was 75 mph day or night for cars and 65 mph day or night for trucks. Other rural highways had a maximum speed limit of 65 mph day and 55 mph night for cars and 50 mph day or night for trucks. Many of these other class roadways also had separate day and night speed limits as well.
Texas is the only state that does not prescribe a different speed limit for each road type in its state or federal highway system. Texas law generally prescribes a statutory speed limit of 70 miles per hour (113 km/h) for any rural road that is numbered by the state or federal government (United States Numbered Highways and Interstate Highways)—whether two lane, four lane, freeway, or otherwise—60 miles per hour (97 km/h) for roads outside an urban district that are not federal or state highways, and 30 miles per hour (48 km/h) for streets in an urban district.
The law allows raising or lowering the statutory limit only if an engineering and traffic investigation indicates that a different limit is appropriate. Texas allows a speed limit of up to 75 miles per hour (121 km/h) to be posted on federal or state highways, city maintained roads, and toll roads, and up to 70 miles per hour (113 km/h) on county roads. Through a separate provision, speed limits up to 80 or 85 mph can be established on certain highways.
Texas has a variable speed limit pilot program by which variable speed limits will be established on I-35 in Temple, on Loop 1604 in San Antonio, and on I-20 in Eastland County. The purpose of the program is to address "inclement weather, congestion, road construction, or any other condition that affects the safe and orderly movement of traffic on a roadway." The pilot program expires February 1, 2015. The legislation establishing the program requires the Texas Transportation Commission to issue a report by December 31, 2014 describing the program and its results, and recommending statutory changes based on the results.
Truck speed limits
Texas once had separate, systemwide truck speed limits, but they were repealed in 1999 and 2011.
The truck speed limit used to be 60 mph (97 km/h) day/55 mph (89 km/h) night when the regular limit was higher. This speed limit did not apply to buses or to trucks transporting United States Postal Service mail.
Truck speed limits disappeared when all speed limits were capped at 55 mph (89 km/h) in 1974. They reappeared with the introduction of 65 mph (105 km/h) limits in 1987.
Even after this repeal, the Harris County Toll Road Authority erroneously retained the separate truck speed limits on its tollways. The separate truck speed limits were removed with the 2002 adoption of the 55 mph environmental speed limit. The signs did not reappear when a 65 mph limit was imposed, but the truck speed limit sign posts were still standing as of August 2008.
In 2001, a bill allowing 75 mph speed limit on roads in certain counties excluded trucks, introducing a 70 mph truck speed limit on roads with a higher limit. A bill in 2005 allowing 80 mph speed limits still excluded trucks. However, truck speed limits were fully repealed in 2011.
In 2011, On Texas Highway 97, between Texas 80 and US 183, truck speed limit 60/night: 55 signs were erroneously posted after the first eastbound speed limit 60 sign east of Nixon, and after the first westbound speed limit 65 sign west of Gonzales.
Night speed limits
Before September 1, 2011, Texas had a statutory 65 mph (105 km/h) night speed limit on all roads with a higher daytime limit. In 2011, the Texas Legislature banned night speed limits effective September 1, 2011. Also, NIGHT: 55 signs are retained on some sections of county roads in Scurry County, Texas as of 2013. Prior to the differential speed limit repeal, Scurry Co. was the only county to have night speed limits on county roads. Many of the county roads were posted at 60 mph, and still are.
Environmental speed limits
Texas is the first state to lower speed limits for air quality reasons, although the lowered limits may not meaningfully improve air quality.
In roughly a 50-mile (80 km) radius of the Houston–Galveston and Dallas–Ft. Worth regions, the Texas Commission on Environmental Quality convinced the Texas Department of Transportation to reduce the speed limit on all roads with 70 mph (113 km/h) or 65 mph (105 km/h) speed limits by 5 mph. This was instituted as part of a plan to reduce smog-forming emissions in areas out of compliance with the federal Clean Air Act.
Initial studies found that lower speed limits could provide roughly 1.5% of the emissions reductions required for Clean Air Act compliance. However, follow-up studies found that the actual reduction is far less:
- The emissions modeling software initially used, MOBILE 5a, overestimated the emissions contribution of speed limit reductions. Rerunning the models with the next generation software, MOBILE 6, produced dramatically lower emissions reductions.
- Speed checks in the Dallas area performed 1 year after implementation of speed limit reductions show that actual speed reductions are only about 1.6 mph, a fraction of the anticipated 10% (5.5 mph) speed reduction.
With both of these facts combined, it is possible that the speed limit reductions only provide a thousandth of the total emissions reductions necessary for Clean Air Act compliance.
In mid-2002, all speed limits in the Houston–Galveston area were capped at 55 mph (89 km/h). Facing immense opposition, poor compliance, and the finding that lowered speed limits produced only a fraction of the originally estimated emissions reductions, the TCEQ relented and reverted to the 5 mph reduction scheme.
Due to its enormous unpopularity, the Texas Commission on Environmental Quality examined alternatives to the 55 mph speed cap. Analysis suggested that the vast majority of emissions reductions were from reduced heavy truck emissions. A proposed alternative was to restore passenger vehicle limits but retain a 55 mph truck speed limit. Concerns about safety problems and enforceability of such a large differential (up to 15 mph on many roads) scuttled that proposal, and a compromise plan, described above, was enacted that retained uniform, but still reduced, speed limits.
In 2003, the Texas Legislature prospectively banned environmental speed limits, effective September 1, 2003. The wording of the bill allows environmental speed limits already in place to remain, but no new miles of roadway may be subjected to environmental speed limits.
In 2013 TxDOT identified highways in the Dallas-Fort Worth region on which speed limits may be increased in response to 2011 legislation increasing the maximum statewide speed limit. On some roads, the previous speed limits may be restored, and on two stretches of road a speed limit of 75 mph has been proposed. Due to environmental concerns, emissions increases and offsetting measures will be considered before any speed limit increases can be approved.
2009–2010 relaxation of environmental speed limits
In 2009, the North Texas Tollway Authority raised the speed limit by 10 mph on two tollways. Several miles of these tollways had 60 mph environmental speed limits. These new 70 mph limits exceeded what is allowable under the environmental speed limit regime.[Note 2] NTTA was allowed to raise the speed limits by offsetting the higher limits' theoretical emissions increases with other transportation-related emissions reduction measures.
In response, the TCEQ switched the Dallas/Fort Worth area's environmental speed limits to a "transportation control measure". Effectively, instead of explicitly requiring the reduced speed limits, the State Implementation Plan only requires the reduced limits' theoretical emissions reductions. This makes it far simpler to eliminate environmental speed limits as long as some other, novel emissions reduction measure offsets the higher limits' theoretical emissions increase.
75 mph limits
Because Texas law allows 75 mph speed limits on any numbered state highway or city maintained road, it is the only state with 75 mph limits on two-lane roads. Speed studies undertaken by TxDOT in response to legislation passed in 2011 took about 2 years, and the result is that the mileage of highway with a speed limit of 75 mph has increased from about 1,400 to about 19,000. 70 mph speed limits have become rare on Texas interstates. They are retained in stretches of I-10 and I-35 in Bexar County, on I-410, and on I-35 from San Antonio to Austin. Most Texas interstates have been posted at 70 mph, notably in east Texas and the panhandle for 16 years from December 1995/early 1996 to early 2012.
80 and 85 mph limits
Additionally, the Texas Transportation Commission may set any speed limit up to 85 mph on any part of the state highway system if that part is "designed to accommodate travel at that established speed or a higher speed" and an "engineering and traffic investigation" determines the speed is "reasonable and safe".
Currently, the roads with an 80 mph limit are:
- I-10 between mile 61.8 in Hudspeth County ( ) and mile 494 in Kerr County ( )
- I-20 between mile 0 in Reeves County ( ) and mile 89 in Ward County ( ).
- State Highway 45 South from the northern junction with US 183 to the southern junction with I-35 in Travis County. SH 45 North from the northern terminus of its concurrency with SH 130 to the northern junction with US 183 near the Travis/Williamson County border remains at 75 mph.
- State Highway 130 from I-35 north of Georgetown to the northern terminus of its concurrency with US-183 south of Austin.
- The Grand Parkway (SH 99) on Segment E between the Katy Freeway to U.S. 290. 
Currently, the only road with an 85 mph speed limit is a 41 mile portion of Texas State Highway 130 from the northern terminus of its concurrency with US-183 ( ), southward to I-10 near Seguin ( ).
Factoring in rounding (most countries round speed limits to the nearest 5 mph or 10 km/h), the 80 miles per hour (129 km/h) limit is approximately the same speed as the 130 km/h (81 mph) recommended speed on the Autobahn and the actual 130 km/h (81 mph) speed limit for freeway-class roads in thirteen European countries and the Australian Northern Territory.
As of September 2012, the only limits higher than the 85 miles per hour (137 km/h) limit are the 140 km/h (87 mph) limits of Poland, Bulgaria and Abu Dhabi, though some countries like Germany have roads without any posted maximum limit.
US Virgin Islands
For "motorcars, pick-up trucks, or motorcycles", the fastest speed limit in this territory is 55 mph and is found on one road, the divided Melvin H. Evans Highway on the island of St. Croix. Outside of towns, these vehicles are limited to 35 mph unless posted lower, except on the above mentioned divided highway and parts of Centerline Road, which is limited to 40 mph. Within towns, these vehicles are limited to 20 mph.
"Motor trucks and buses" are limited to 40 mph on St. Croix's main divided highway, 30 mph on other highways outside of towns, and 10 mph within towns.
It should be noted that traffic in the USVI drives on the left.
In Utah, there is a minimum speed limit of 45 mph on Interstate Highways when conditions permit. The maximum speed limit on Interstates is 65 mph in cities and, on most highways, 75-80 mph elsewhere. UDOT has now implemented HB83, raising the speed limit to 80 MPH on an additional 289 miles of rural interstate, including I-80 from Nevada to mile marker 99, I-84 from Idaho to I-15, and additional sections of I-15.
- Although 75-80 mph is posted on most interstates, some stretches of I-80 and I-84 are posted at 70 mph east of Salt Lake City. I-80 is briefly posted 65 mph/truck speed: 55 between US 40 and Wanship.
- Speed limit from Ogden to Spanish Fork on I-15 is 65 mph. Other than that, speed limit is 75–80 miles per hour.
- The Legacy Parkway, running between North Salt Lake and Farmington, has posted speed limits of 55 mph along its entire length due to environmental concerns at the time of its construction.
80 mph speed limit
April 3, 2013; UDOT spokesman John Gleason “We’d only do it in a situation that would make sense: flat, straight roadways. The Utah Department of Transportation is looking at expanding zones where it can increase the speed limit from 75 to 80 miles per hour. The Utah State Legislature recently approved a bill allowing for a series of zones to become permanent, as well as expanding them in other places around the state. UDOT began a study on Monday (April 1, 2013) to place more zones on rural parts of I-15, I-80 and I-84. The areas under consideration, UDOT spokesman said, are on I-80 from Grantsville (exit 99) to Wendover, on the Utah-Nevada border; I-84 from Tremonton to the Utah-Idaho border; I-15 from Brigham City (North interchange) to the Utah-Idaho border; and I-15 from Santaquin to North Leeds." The speed limit on these sections has been increased from 75 mph to 80 mph as of September 17, 2013.
On February 13, 2014, UDOT voted to increase the speed limit on I-80 from Salt Lake City across the Bonneville Salt Flats to the Nevada border to 80 miles per hour (130 km/h). The change went into effect on July 1, 2014. By July 1, 2014, the state raised the speed limit on all rural interstates in Utah to 80 mph except I-80 from the Wyoming border to Salt Lake City, on I-84 from its junction with I-80 to Ogden and on twisty sections of Interstate 70 from its I-15 junction to the Colorado border (the speed limit on I-70 varies between 60 mph and 75 mph depending on the topography of the section of freeway.).
The standard speed limit in Vermont stands at 50 mph. This is applied to rural two-lane roads. On urban freeways, the speed limit is 55 mph, such as on I-189 and Interstate 89 in Burlington. Rural interstate freeways are posted at 65 mph Furthermore, the speed limit drops from 65 mph on rural highways to 40 mph at the approach to the Canadian border on Interstates 89 and 91, at Highgate and Derby Line, respectively. In school zones, the speed limit can range from 15 mph to 25 mph, depending on local authority. The minimum speed is defined at 40 mph only on Interstate highways. That includes where the limit is posted at 55 and 65 mph. However, as old signs are being replaced, the "40 MINIMUM" is being phased out, keeping only "SPEED LIMIT 65".
Rural freeways generally have 70 mph limits. All urban interstates in Virginia have a default limit of 55 mph but can be raised up to 65 based on an engineering study. Most non-interstate four lane highways in Virginia carry a 60 mph limit, while two lane roads remain restricted to 55 mph.
A Virginia statute provides that the default speed limit "shall be 55 mph on interstate highways or other limited access highways with divided roadways, nonlimited access highways having four or more lanes, and all state primary highways." "The maximum speed limit on all other highways shall be 55 miles per hour if the vehicle is a passenger motor vehicle, bus, pickup or panel truck, or a motorcycle, but 45 miles per hour on such highways if the vehicle is a truck, tractor truck, or combination of vehicles designed to transport property, or is a motor vehicle being used to tow a vehicle designed for self-propulsion, or a house trailer." The same statute contains a number of exceptions, however, allowing higher speed limits "where indicated by lawfully placed signs, erected subsequent to a traffic engineering study and analysis of available and appropriate accident and law-enforcement data." This provision allows speed limits of up to 70 mph on Interstate highways; multilane, divided, limited-access highways; and high-occupancy vehicle lanes if said lanes are physically separated from the regular travel lanes. (As of September 2013, Virginia has two such barrier-separated HOV facilities, on I-95 and I-395 in Northern Virginia and on I-64 in the Tidewater area; in addition, I-495 has barrier-separated high-occupancy/toll "Express Lanes".) The statute also allows 60-mph speed limits on a number of specified non-limited access, multilane, divided highways.
The 70-mph provision was added to Section 46.2-870 via an amendment effective on July 1, 2010. The previous version of the statute had authorized a 70-mph speed limit only on I-85; the maximum limit permitted elsewhere was 65 mph. Notably, the revised statute does not require a 70-mph speed limit on any road nor make such limit automatic, due to the requirement for traffic and engineering studies. The Virginia Department of Transportation began studying Interstate highways with 65-mph speed limits during April 2010 to determine which roads should receive the 70-mph limit and announced that the studies would be conducted in three phases over a period of several months, with the initial phase focusing on 323 miles of highway with "no significant levels of crashes and congestion." As of July 1, 2010, VDOT increased the speed limit to 70 mph on a portion of one highway (I-295 south of I-64). On October 20, 2010, Governor Bob McDonnell announced that by the end of 2010, VDOT would post 70-mph speed limits on 680 miles of Virginia Interstates located outside of urban areas, representing 61 percent of Virginia's total 1,119 miles of Interstate highways. The amended statute allows 70-mph speed limits on routes other than Interstates. Initially VDOT declined to consider any such routes for the higher limit, but in early 2012 VDOT announced that a 70-mph limit would be posted on a portion of US-29 near Lynchburg.
Other Virginia statutes prescribe exceptions to the general rules set forth above. The notable aspect of Virginia's current speed limit laws is that the Department of Transportation has no authority to raise speed limits above the statutory limits unless the General Assembly passes a statute permitting the change. Since the National Maximum Speed Law was repealed in 1995, such statutory exceptions were largely confined to a highway-by-highway basis, as evidenced by the list of 60-mph exceptions in Va. Code § 46.2-870.
Notably, Virginia's reckless driving statute provides that driving 20 mph over the speed limit, or in excess of 80 mph regardless of the posted speed limit, is grounds for a reckless driving ticket. Thus, in a 70-mph zone traveling 11 mph over the speed limit is prosecutable as a misdemeanor with penalties of up to a $2,500 fine and/or 12 months in jail.
Virginia law does not prescribe a fixed minimum speed limit, although a statute does authorize the posting of such limits where traffic and engineering studies indicate that they would be appropriate.
Virginia is the only state that prohibits the use of radar detectors (the District of Columbia does as well, though it is not a state).
The typical speed limit on a Washington freeway is 70 mph rural, 60 mph urban, with a truck speed limit no higher than 60 mph. The posted truck speed limit also applies to any vehicle towing a trailer. Limits were raised to these speeds following the elimination of the federal 55 mph speed limit, to more closely reflect the common speeds of traffic at that time. However, Washington State does not have a standard legislated statewide speed limit, leaving it to WSDOT to set individual speed limits for specific segments of road. This has resulted in a wide range of speed limits statewide, with many rural undivided 2 lane highways set at 65 mph, while some congested urban divided highways have limits as low as 40 mph.
The default speed limit on a rural 2-lane highway in Washington is 60; however, the limit on undivided highways varies. In mountainous country like the Cascades and Olympic Mountains, certain twisty roads are limited to 55 mph, whereas some flat, straight highways in eastern Washington have a limit of 65. The speed limit for motorhomes and autos with trailers is 60 like it is for trucks. Roads with traffic lights are limited to 50 mph. The school zone speed limit is 20 mph but is in effect only if children are present.
In 1997, the speed limit on most rural Interstates was raised from 65 mph to 70 mph. Urban Interstate speed limits generally vary from 55 mph to 65 mph. Sections of I-64 and I-68 have lower truck speed limits due to steep grades; otherwise, West Virginia does not post separate truck speed limits.
Speed limits on 4-lane divided highways are normally 65 mph although some stretches within cities are posted as low as 50&nsbp;mph. Open country highways have a statutory limit of 55 mph which includes most rural two-lane highways and even includes some one lane back country roads or any road without a posted speed limit. Cities and towns set their own speed limits which are usually between 25 and 55 mph. School zones have a statutory speed limit of 15 mph. Speed limits are commonly reduced by 15 mph in work zones.
The state of Wisconsin's speed limits are set out in statutory law but may often be modified by the maintaining government entity. In addition to a basic speed rule, Wisconsin law specifies certain occasions where reduced speeds are required including—and not limited to the approaches and traverses of rail crossings, winding roads, roads where people are present, and the crests of grades. Although there is no numeric minimum speed limit, state law prohibits the impediment of traffic by unreasonably slow speeds. Vehicles which lack rubber tires filled with compressed air have a hard limit of 15 mph.
The state of Wisconsin has four default speed limits. 15 mph limits apply in school zones, near parks with children, and in alleys. 5 mph default speed limits apply, unless modified by the managing authority, on "service roads" within corporate limits. Within municipal boundaries and in areas of dense urban development a 35 mph limit is in effect unless another speed limit is indicated. In some jurisdictions, the 25 mph limit is the default speed limit for residential areas. The entry to such an area is to be marked by speed limit signs. Outside of built-up areas (these include denser business, industrial or residential land uses according to the relevant law) a 55 mph limit is effective in the absence of other indications.
Along with the aforementioned default speed limits, there are other statutory speed limits which more often require signs to be effective. 65 mph limits on freeways and expressways require signs to be effective. The default speed limit on these types of roads is 55 mph as they do not directly interact with the built-up environment. In the densest urban districts a statutory 25 mph limit is effective when adequate signage is used, as are 35 mph limits in areas of light development. The same applies to 45 mph limits on highways designated as "rustic" roads. However, "an alleged failure to post [such a speed limit sign] is not a defense to a prosecution" in the case of such statutory limits.
Wyoming's highest speed limit is 80 mph, found on its Interstate highways, and 65 mph on its four lane divided highways. The speed limit for school zones is 20 mph, 30 mph in urban districts and residential areas, 65 mph for other paved roads, and 55 mph for unpaved roads.
In February 2014, the state Assembly passed a bill that would raise the speed limit from 75 to 80 mph on certain freeway segments that would meet safety standards. The bill passed the Senate on Feb. 25 and raised the speed limit on certain freeway sections to 80 on July 1, 2014. However, an attempt to raise the speed limit to 70 on two lane highways such as Wyoming 120 and US 14 was turned down that same month.
- Public opposition to speed limits being set by an authority, often arise because such agency has been viewed as abusing its' power--such as by arbitrary indiscretion or by creating "speed traps." Because an expert can theoretically calculate a safer speed limit, than the populace's vote by driving, it is beneficial that local governments preserve strong public trust with their integrity in speed regulation. See A Policy on Geometric Design of Highways and Streets, AASHTO, 4th Ed., 2001; ISBN 1-56051-156-7
- For clarity, a substantial portion of NTTA roadways were never subjected to environmental speed limits, including the parts of the Dallas North Tollway which never had a 65 mph or higher limit or any road segment opened after the Texas Legislature's prospective environmental speed limit ban.
- Alabama Department of Public Safety rem New link for Alabama DPS Speed Limits http://www.dps.alabama.gov/Home/wfContentTableColumned.aspx?ID=40&PLH1=HPSPEEDLIMITS
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- "Dorman v. Taylor, 113 Cal. App. 2d 505". Official California Appellate Reports, 2nd Series (California Appellate Court; Bancroft-Whitney; LexisNexis) 113: 505. Oct 3, 1952. Retrieved 2013-09-01. (driver negligent in negotiating turn at speed too great to control vehicle. See CA Reports Official Headnote #) and California Official Reports: Online Opinions
- "Hatzakorzian v. Rucker-Fuller Desk Co., 197 Cal. 82". Official California Reports, Vol. 197, p. 82 (California Supreme Court reporter). September 21, 1925. Retrieved 2013-07-27. "Under the circumstances of the present case -- the narrowness of the unpaved portion of the highway, the darkness of the night and the blinding of Kennell by the glare of the lights reflected from the headlights of the approaching machine -- the highway over which Kennell was traveling was beset by danger of an extraordinary character from the time his vision became so obscured as to make it impossible for him to see plainly the road before him to the time that he struck the deceased. Thus the ordinary care with which Kennell was charged in driving his car over the highway required such an amount of such care as was commensurate with the exactions of the extraordinary dangerous circumstances under which he was then operating his car. The respective rights and duties of drivers of automobiles and other vehicles and of pedestrians have repeatedly been by the courts of this state clearly pointed out.."
- "Bove v. Beckman, 236 Cal. App. 2d 555". Official California Appellate Reports, 2nd Series (California Appellate Court; Bancroft-Whitney; LexisNexis) 236: 555. Aug 16, 1965. Retrieved 2013-09-01. ""A person driving an automobile at 65 miles an hour on a highway on a dark night with his lights on low beam affording a forward vision of only about 100 feet was driving at a negligent and excessive speed which was inconsistent with any right of way that he might otherwise have had." (CA Reports Official Headnote #)" See California Official Reports: Online Opinions
- Allin v. Snavely, 100 Cal. App. 2d 411. Official California Appellate Reports (2nd Series Vol. 100, p. 411). Nov 14, 1950. Retrieved 2013-07-27. ""A driver by insisting on his lawful right of way may violate the basic speed law as provided by Veh. Code, § 22350, and thus become guilty of negligence."(CA Reports Headnote #)" See California Official Report Online
- "Lutz v. Schendel, 175 Cal. App. 2d 140". Official California Appellate Reports, 2nd Series (California Appellate Court; Bancroft-Whitney; LexisNexis) 175: 140. Nov 6, 1959. Retrieved 2013-09-01. "It is the duty of the driver of a motor vehicle using the public highways to be vigilant at all times and to keep the vehicle under such control that to avoid a collision he can stop as quickly as might be required of him by eventualities that would be anticipated by an ordinarily prudent driver in like position." See California Official Reports: Online Opinions
- "Falasco v. Hulen, 6 Cal. App. 2d 224". Official California Appellate Reports, 2nd Series (California Appellate Court; Bancroft-Whitney; LexisNexis) 6: 224. April 17, 1935. Retrieved 2013-09-01. ""Driving between 60 and 65 miles an hour over the brow of a hill, where one's view is obstructed and one cannot see what is on the opposite side of the hill for a sufficient distance to control the speed of his car, is an act showing a reckless disregard of the safety of others; and in said action, under the evidence, the jury was entitled to conclude either that defendant was driving at such a reckless rate of speed that he could not control the car, or that he was driving at such a high rate of speed that he did not perceive that the highway ahead of him afforded an unobstructed passage." (CA Reports Official Headnote #)" See California Official Reports: Online Opinions
- "Riggs v. Gasser Motors, 22 Cal. App. 2d 636". Official California Appellate Reports (2nd Series Vol. 22, p. 636). September 25, 1937. Retrieved 2013-07-27. "It is common knowledge that intersecting streets in cities present a continuing hazard, the degree of hazard depending upon the extent of the use of the intersecting streets and the surrounding circumstances or conditions of each intersection. Under such circumstances the basic [speed] law...is always governing." See Official Reports Opinions Online
- "Leeper v. Nelson, 139 Cal. App. 2d 65". Official California Appellate Reports (2nd Series Vol. 139, p. 65). Feb 6, 1956. Retrieved 2013-07-27. "The operator of an automobile is bound to anticipate that he may meet persons or vehicles at any point of the street, and he must in order to avoid a charge of negligence, keep a proper lookout for them and keep his machine under such control as will enable him to avoid a collision with another automobile driven with care and caution as a reasonably prudent person would do under similar conditions." See Huetter v. Andrews, 91 Cal. App. 2d 142, Berlin v. Violett, 129 Cal.App. 337, Reaugh v. Cudahy Packing Co., 189 Cal. 335 , and Official Reports Opinions Online
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