30 kph zone
Encyclopedia
The 30 kph Zone, or 20 mph Zone, is a form of urban intervention where an area is designated with a 30 kilometer per hour (kph) limit, or 20 mile per hour (mph) limit. Note that 30 kph equals 19 mph, but 20 mph is more commonly used. The 20 mile per hour zone can be through signing
and/or through physical traffic calming
measures.
measures and new roadway surfacing such as the brick surfacing so common in Dutch
30 kph zones can be cost-prohibitive for communities with limited resources.
; and at 40 mph, fully 90% of crashes are fatal
. The dramatic differences in fatality rates are a key part of the theory behind 20 mph zones.
that seeks to strike a balance between the realities of an urban area bustling with pedestrian activity and the circulatory function of the roadways. It is considered to be a space for people who live, work, play and study in the area, not for people who cross the zone to get somewhere else. The theory is to reduce rat running while improving the safety and quality of life in the area.
The objectives of the implementation of a 20 mph Zone are:
, Austria
, became the first European
city to implement a city-wide 30kph limit on all roads except its largest. Significant 30 kph zones are ubiquitous across the Netherlands
and are gaining popularity in the UK. In Switzerland
30 kph zones have been allowed by law since 1989 and they were first established in Zurich
in 1991.
To date, the popularity of 20 mph zones in the United Kingdom
has not yet caught on in the United States
. By one estimate, some 3 million people live in areas with 20 mph speed limits in the UK. Outside of Europe
, the traffic calmed zones are catching on but slowly. Mexico City
is considering a proposal for a one square kilometer “Zona 30” area in a central part of the city known as La Colonia Roma
. In the US, 20 mph speed limits exist along linear routes, but are slow to catch on for area-wide implementation. New York City
is leading the way with neighborhood-scale 20 mph zones and is currently re-engineering 60 miles of streets per year for conversion to 20 mph zones.
Ten US states already allow 15 mph or 20 mph speed limits for linear routes, as follows:
Alaska
stipulates 15 mph speed limits in alleys and 20 mph limits in business districts.
In Delaware
school zones have 20 mph speed limits.
Florida
has school zones which usually have 10 mph to 20 mph limits. Most use signing and flashing yellow lights during school times, but there is debate surrounding the efficacy of these measures.
Massachusetts
has set their default speed limit at 15 mph in the vicinity of a mobile vendor with flashing yellow lights (such as an Ice Cream Truck) and at 20 mph in a school zone when children are present.
In North Carolina
, the Central Business Districts (CBDs) have a statutory speed limit of 20 mph unless otherwise posted. They use "Reduce Speed Ahead" signage instead of the more common "Reduced Speed Ahead" signage.
In Oregon
, rather than having a “when children are present” speed limit, they have a 20 mph speed limit with a time-of-day system, usually school days, 7 a.m. to 5 p.m. The speed limit is for school roads with posted speeds of 30 mph or below.
Pennsylvania
generally uses 15 mph speed limits for school zones during arrival and departure times.
In Rhode Island
the default speed limit is 20 mph within 300 feet of a school, which starts to emulate a 20 mph zone but is not an area-wide speed limit.
In West Virginia
school zones have a statutory speed limit of 15 mph, except for roads with a speed limit of 55 mph or higher, which have an advisory speed of 35 mph in school zones when children are present. A school zone includes 200 feet adjacent to the school (or school road) in both directions.
Wisconsin
has a default speed limit of 15 mph in school zones, near parks with children, and in alleyways.
Traffic sign
Traffic signs or road signs are signs erected at the side of roads to provide information to road users. With traffic volumes increasing over the last eight decades, many countries have adopted pictorial signs or otherwise simplified and standardized their signs to facilitate international travel...
and/or through physical traffic calming
Traffic calming
Traffic calming is intended to slow or reduce motor-vehicle traffic in order to improve the living conditions for residents as well as to improve safety for pedestrians and cyclists. Urban planners and traffic engineers have many strategies for traffic calming...
measures.
Disadvantages
Some research points out that simply signing streets has little effect in slowing speeds. Moreover, more comprehensive measures such as implementing vertical and horizontal traffic calmingTraffic calming
Traffic calming is intended to slow or reduce motor-vehicle traffic in order to improve the living conditions for residents as well as to improve safety for pedestrians and cyclists. Urban planners and traffic engineers have many strategies for traffic calming...
measures and new roadway surfacing such as the brick surfacing so common in Dutch
Dutch
Dutch usually refers to:*Something from or related to the Netherlands*Dutch people, people from the Netherlands or their descendants*Dutch language, spoken in the Netherlands, Belgium, Suriname, Curaçao, Aruba, Bonaire, Saba, Sint Maarten, and Sint Eustatius.* Something associated with German, ...
30 kph zones can be cost-prohibitive for communities with limited resources.
Advantages
Research has shown that reducing driver speeds in built-up areas reduce injuries for all road users, including motorists, bicyclists, and pedestrians. Aside from safety benefits, bicyclists and pedestrians tend to be more comfortable and more prevalent in areas with 20 mph speeds. Other studies have revealed that lower speeds reduce community severance caused by high speed roads. Research has shown that there is more neighborhood interaction and community cohesion when speeds are reduced to 20 mph.Safety affects of lower speeds
The link between vehicle speed and pedestrian crash severity has been established by research studies, with crash severity increasing as a function of motor vehicle speeds. If a vehicle hits a pedestrian while traveling 15 mph, most pedestrians will survive a crash, often sustaining only minor injuries. Minor increases in impact speed have been shown to have a profound effect on crash severity. At 25 mph, almost all crashes result in severe injuries and roughly half are fatalFatal
Fatal may refer to:* Causing death* Fatal , an album by Hussein Fatal* Fatal Recordings, a feminist record label* Fatal, a rapper who collaborated with the band Therapy? on the song "Come and Die" from the Judgment Night film soundtrack...
; and at 40 mph, fully 90% of crashes are fatal
Fatal
Fatal may refer to:* Causing death* Fatal , an album by Hussein Fatal* Fatal Recordings, a feminist record label* Fatal, a rapper who collaborated with the band Therapy? on the song "Come and Die" from the Judgment Night film soundtrack...
. The dramatic differences in fatality rates are a key part of the theory behind 20 mph zones.
Philosophy
The driving philosophy behind a 20 mph zone is that it considers the streets in the zone to be a public spacePublic space
A public space is a social space such as a town square that is open and accessible to all, regardless of gender, race, ethnicity, age or socio-economic level. One of the earliest examples of public spaces are commons. For example, no fees or paid tickets are required for entry, nor are the entrants...
that seeks to strike a balance between the realities of an urban area bustling with pedestrian activity and the circulatory function of the roadways. It is considered to be a space for people who live, work, play and study in the area, not for people who cross the zone to get somewhere else. The theory is to reduce rat running while improving the safety and quality of life in the area.
The objectives of the implementation of a 20 mph Zone are:
- Provide safe street crossings
- Improve the quality of life
- Increase levels of walking and cycling
- Reduce obesity through increased active living
- Reduce rat running and cut through traffic
- Reducing motor vehicle traffic volumes and speeds
- To reduce road crash rates, injuries and fatalities to all road users
- Reduce greenhouse gas emissions, air pollution and noise pollution
- Foment an area where pedestrians, cyclists and motorists coexist safely and comfortably
- Develop public space that is open and safe for everyone, including people with disabilities
- Increase the space available for walking, biking, and people on the street to eat, play and enjoy life
- Provide a safe area for children in school zones
- Increase real estate values of local homes and businesses
- Increase the economic vitality of the area
- Strengthen the sense of community
Prevalence
In European countries 30 kph zones have been used widely. On September 1, 1992, the city of GrazGraz
The more recent population figures do not give the whole picture as only people with principal residence status are counted and people with secondary residence status are not. Most of the people with secondary residence status in Graz are students...
, Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
, became the first European
European
European may mean:* A person or attribute of the continent of Europe* A citizen or attribute of or from the European Union** See also: Citizenship of the European Union* A person from a European ethnic group, or descended from one:** European American...
city to implement a city-wide 30kph limit on all roads except its largest. Significant 30 kph zones are ubiquitous across the Netherlands
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
and are gaining popularity in the UK. In Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
30 kph zones have been allowed by law since 1989 and they were first established in Zurich
Zürich
Zurich is the largest city in Switzerland and the capital of the canton of Zurich. It is located in central Switzerland at the northwestern tip of Lake Zurich...
in 1991.
To date, the popularity of 20 mph zones in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
has not yet caught on in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. By one estimate, some 3 million people live in areas with 20 mph speed limits in the UK. Outside of Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, the traffic calmed zones are catching on but slowly. Mexico City
Mexico City
Mexico City is the Federal District , capital of Mexico and seat of the federal powers of the Mexican Union. It is a federal entity within Mexico which is not part of any one of the 31 Mexican states but belongs to the federation as a whole...
is considering a proposal for a one square kilometer “Zona 30” area in a central part of the city known as La Colonia Roma
Colonia Roma
Colonia Roma is a colonia or neighborhood located in the Cuauhtémoc borough of Mexico City just west of the city’s historic center. The area was a very shallow part of Lake Texcoco, dotted with tiny islands and one small island village of Aztacalco during the pre-Hispanic period...
. In the US, 20 mph speed limits exist along linear routes, but are slow to catch on for area-wide implementation. New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
is leading the way with neighborhood-scale 20 mph zones and is currently re-engineering 60 miles of streets per year for conversion to 20 mph zones.
Ten US states already allow 15 mph or 20 mph speed limits for linear routes, as follows:
Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
stipulates 15 mph speed limits in alleys and 20 mph limits in business districts.
In Delaware
Delaware
Delaware is a U.S. state located on the Atlantic Coast in the Mid-Atlantic region of the United States. It is bordered to the south and west by Maryland, and to the north by Pennsylvania...
school zones have 20 mph speed limits.
Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
has school zones which usually have 10 mph to 20 mph limits. Most use signing and flashing yellow lights during school times, but there is debate surrounding the efficacy of these measures.
Massachusetts
Massachusetts
The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...
has set their default speed limit at 15 mph in the vicinity of a mobile vendor with flashing yellow lights (such as an Ice Cream Truck) and at 20 mph in a school zone when children are present.
In North Carolina
North Carolina
North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...
, the Central Business Districts (CBDs) have a statutory speed limit of 20 mph unless otherwise posted. They use "Reduce Speed Ahead" signage instead of the more common "Reduced Speed Ahead" signage.
In Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
, rather than having a “when children are present” speed limit, they have a 20 mph speed limit with a time-of-day system, usually school days, 7 a.m. to 5 p.m. The speed limit is for school roads with posted speeds of 30 mph or below.
Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
generally uses 15 mph speed limits for school zones during arrival and departure times.
In Rhode Island
Rhode Island
The state of Rhode Island and Providence Plantations, more commonly referred to as Rhode Island , is a state in the New England region of the United States. It is the smallest U.S. state by area...
the default speed limit is 20 mph within 300 feet of a school, which starts to emulate a 20 mph zone but is not an area-wide speed limit.
In West Virginia
West Virginia
West Virginia is a state in the Appalachian and Southeastern regions of the United States, bordered by Virginia to the southeast, Kentucky to the southwest, Ohio to the northwest, Pennsylvania to the northeast and Maryland to the east...
school zones have a statutory speed limit of 15 mph, except for roads with a speed limit of 55 mph or higher, which have an advisory speed of 35 mph in school zones when children are present. A school zone includes 200 feet adjacent to the school (or school road) in both directions.
Wisconsin
Wisconsin
Wisconsin is a U.S. state located in the north-central United States and is part of the Midwest. It is bordered by Minnesota to the west, Iowa to the southwest, Illinois to the south, Lake Michigan to the east, Michigan to the northeast, and Lake Superior to the north. Wisconsin's capital is...
has a default speed limit of 15 mph in school zones, near parks with children, and in alleyways.