Cul-de-sac
Encyclopedia
A cul-de-sac (literally "bottom of bag" in French
) is a word of French origin referring to a dead end, close, no through road (British English
) or court (American
, Canadian
and Australian English
) meaning dead-end street with only one inlet/outlet. While historically built for other reasons, one of its modern uses is to calm vehicle traffic
.
The earliest example of cul-de-sac streets was unearthed in the El-Lahun
workers village in Egypt
, which was built circa 1885 BCE. The village is laid out with straight streets that intersect at right angles; akin to a grid, but irregular. The western part of the excavated village, where the workers lived, shows fifteen narrow and short dead-end streets laid out perpendicularly on either side of a wider, straight street; all terminate at the enclosing walls.
In the UK, their prior existence is implied by an 1875 law which banned their use in new developments.
Inferential evidence of their earlier use can also be drawn from the text of a German
architect, Rudolf Eberstadt, that explains their purpose and utility: “We have, in our medieval towns, examples of the old non-traffic street, showing very commendable methods of cutting up the land. I ought to mention here that to keep traffic out of residential streets is necessary not only in the general interest of the population, but, above all, for the sake of the children, whose health (amongst the working class
es) is mainly dependent on the opportunity of moving about in close connection with their dwelling places, without the danger of being run over. In the earlier periods, traffic was excluded from residential streets simply by gates or by employing the cul-de-sac”.
It was in the UK that the cul-de-sac street type was first legislated into use, with “The Hampstead Garden Suburb Act, 1906”. The proponents of the Act, Raymond Unwin
and Barry Parker, thus gained permission to introduce culs-de-sac in their subsequent site plans, and they promoted it as a suitable street type for Garden Suburbs. Unwin's applications of the cul-de-sac and the related crescent always included pedestrian paths independent of the road network. This design feature reflects the predominance of pedestrian movement for local trips at the turn of the 20th century, and presages the current planning priority for increased pedestrian accessibility. The 1906 Act defined the nature of the cul-de-sac as a non-through road and restricted its length to 500 feet (152.4 m). Garden cities
in the UK that followed Hampstead, such as Welwyn Garden City
all included culs-de-sac (see photo).
In the 1920s, the garden city movement gained ground in the US and, with it, came its design elements, such as the cul-de-sac. Clarence Stein
, a main proponent of the movement, incorporated it in the Radburn, NJ subdivision, which was to become a model for subsequent neighbourhood developments. The US Federal Housing Authority recommended and promoted their use through their 1936 guidelines and the power of lending development funds.
In Canada
, a variation of Stein’s Radburn 1929 plan that used crescents (loops) instead of culs-de-sac was built in 1947 in Winnipeg
, Manitoba Wildwood Park, designed by Hubert Bird. In 1954, the Central Mortgage and Housing Corporation published its own guidelines in which the cul-de-sac was strongly recommended for local streets and, as the FHA in the US, used its lending power to see its inclusion in development plans. The Varsity Village and Braeside, subdivisions in Calgary
, Alberta
also used the Radburn model in the late 1960s.
In the 1960s the cul-de-sac attained systematic international application in planned new cities such as Doxiadis’ Islamabad
(1960). In the UK new towns such as Harlow
(1947) by Sir Frederick Gibberd and Milton Keynes
(1967) incorporated culs-de-sac and crescents in their layouts.
Planning theorists also advocated the use of culs-de-sac and crescents most notably, Christopher Alexander, in his “A Pattern Language
” 1977 book (pattern #49). Doxiadis also argued their important role in separating man from machine.
Unplanned culs-de-sac
Virtual, unplanned culs-de-sac have appeared in the centers of cities which are laid on a grid. Whole neighbourhood street reconfigurations emerged in several cities including Berkeley CA, Seattle WA and Vancouver BC. This transformation of sections of the grid plan
since the 1970s has occurred in response to the need for the following:
This selective, sporadic transformation continues into the 21st century. As traffic volumes increase and as cities decide to remove or reduce traffic on specific streets of central areas, streets are closed off using bollards or landscaping thus creating new, unplanned cul-de-sac streets and produce a new, functional blend of the inherited grid with newer street types. A recent variation of limiting traffic is the managed closure by using retractable bollards which are activated by designated card holders only.
culs-de-sac are created to limit through-traffic in residential areas. While some cul-de-sac streets provide no possible passage except in and out of their road entry, others allow cyclists, pedestrian
s or other non-automotive traffic to pass through connecting easements or paths.
This design improvement, which selectively excludes one mode of transport while permitting others, can be viewed as an example of “filtered permeability
”. Its application retains the cul-de-sac’s primary function as a non-through road, but establishes complete pedestrian and bicycle network connectivity.
In traffic engineering
parlance, the cul-de-sac defines the local street as having primarily an 'access' (to properties) function rather than as one having a 'transport' or 'through' function.
, new subdivisions
in the United States and Canada, as well as New Towns in England and other countries have made extensive use of the cul-de-sac and crescent (loops) street types. Typically, there is one or several central roads in the subdivision with many cul-de-sac streets of varying length, branching out from the main roads, to fill the land in the subdivision; a dendrite or hierarchical
pattern. Since the 1960s, this pattern has been the dominant road network structure of suburbs and exurbs in the United States, Canada, and Australia. It is also increasingly popular in Latin America
, Western Europe
, and China
. In this pattern, there are only a few roads (relative to the number of cul-de-sac streets) leading out of the subdivision and into other subdivisions or onto major roads.
In the US, these changes can be attributed to real-estate developers' desire to meet FHA
guidelines and make federal home loans available to their consumers. In Canada a similar incentive was provided to developers by CMHC
. These incentives, which were discontinued in the 70s, gave the initial impetus for the application of the hierarchical pattern. In other countries such incentives do not exist and its adoption is motivated by consumer preferences.
Nineteenth and early 20th century American urban planning
, emphasized a grid plan
, partly out of extensive reliance on foot, horse and streetcars for transportation. In such earlier urban development, alleys were included to allow for deliveries of soiled supplies, such as coal, to the rear of houses which are now heated by electricity, piped natural gas or oil.
The use of culs-de-sac reduces the amount of car traffic on residential streets within the subdivision, thus reducing noise, air pollution and the probability of accidents. Ben-Joseph (1995) and Lovegrove/Sayed (2006) indicate a substantially lower collision rate for street networks based on the cul-de-sac street type. Dumbaugh and Rae (2009) suggest that land use patterns play a significant role in traffic safety and should be considered in conjunction with the network pattern. While all intersection types in general reduce the incidence of fatal crashes, four-way intersections, which rarely occur in a network with cul-de-sac or loop streets, increase total and injurious crashes significantly. The study recommends hybrid street networks with dense concentrations of T-intersections and concludes that a return to the 19th century gridiron is undesirable.
This decrease in traffic, in turn, is thought to lower the incidence of crime and increase desirability, because in most cases the people who traverse the cul-de-sac either live there or are guests of those who do. CPTED planning principles suggest increased natural surveillance and sense of ownership as a means of fostering security in a neighbourhood. Both of these phenomena occur naturally on a cul-de-sac street as does social networking. Design guidelines based on the CPTED perspective recommend its use for these reasons.
Cul-de-sac streets increase spontaneous outdoor activity by children. A study in California examined the amount of child play that occurred on the streets of neighbourhoods with different characteristics; grid pattern and culs-de-sac. The findings indicate that culs-de-sac showed substantial increase in play activity than the open grid street pattern. Culs-de-sac reduce perceived danger from traffic thereby encouraging more outdoor play.
Similar studies in Europe and Australia found that children’s outdoor play is significantly reduced on through roads where traffic is, or perceived by parents to be, a risk. In addition, they confirmed the results of the seminal Donald Appleyard
1982 study which showed the negative correlation between amount of traffic and social networks. These studies recommend the use of the cul-de-sac or strong traffic calming measures. When culs-de-sac are interconnected with foot and bike paths, as for example in Vauban, Freiburg
, Village Homes
, Davis, California, they can increase active modes of mobility among their residents.
Real estate developers prefer culs-de-sac because they allow builders to fit more houses into oddly shaped tracts of land and facilitate building to the edges of rivers and property lines. They also choose these discontinuous network patterns of cul-de-sac and loop streets because of the often significant economies in infrastructure costs compared to the grid plan
.
From an environmental perspective, culs-de-sac allow greater flexibility than the common grid in adapting to the natural grades of a site and to its ecologically sensitive features, such as streams creeks and mature forest growth.
The desirability of the cul-de-sac street type among home buyers is implied by the evidence that they often pay up to a 20% premium for a home on such a street, according to one study. This could be because there is considerably less passing traffic, resulting in less noise and reduced actual or perceived risk, increasing the sense of tranquility. A survey of residents on three types of streets: cul-de-sac, loop, and through (grid) recorded their preferences among these types. It found that 82% of cul-de-sac residents preferred their own street type, 18% preferred a loop, and 0% the grid. Only 13% of grid street residents preferred their own type and 54% would choose a cul-de-sac to live on.
Two other studies, reported in 1990 and 2009 respectively, confirmed this upward trend and determined the premium that cul-de-sac streets command. The first found a 29% premium over the streets in a grid. The second, focused on trails and greenbelts, found that other amenities including cul-de-sac streets add significantly to the home value.
The positive feelings that a cul-de-sac street could evoke, that residents value, are expressed vividly by Allan Jacobs
in describing a short (250 ft), narrow (60 ft), and densely built (14 du/acre) cul-de-sac in the Shadyside
neighborhood of Pittsburgh, Pennsylvania: “Step into Roslyn Place and you are likely to sense, immediately, that you are in a place, a special place, a handsome place, a safe place, a welcoming place, a place where you might wish to live.” ... “narrowness and enclosure and intimacy bring a feeling of safety to Roslyn Place... “Stay on our street” is all the kids have to know.”
Gated communities
, steadily increasing worldwide, employ cul-de-sac and loop street networks because, having a dendrite structure, they reduce the number of through roads and, consequently, the corresponding number of entries and exits to be controlled.
An extensive analysis of the research evidence by TRB,
however, shows only an association between the built environment and physical activity levels, not causal connections. The evidence does not either identify with certainty which characteristics of the built environment are most closely associated with physical activity behaviour. The study also warns against confusing inadequate physical activity with obesity which is the outcome of an energy imbalance. Many contemporary lifestyle trends some inevitable (sedentary work) and some avoidable, (frequent energy-rich food consumption or TV watching [4 h/d]), contribute to this imbalance and must be considered in understanding and combating obesity
.
The imperemability deficiency of the typical cul-de-sac street can be addressed by applying a modified, improved version of it, mentioned above, that enables pedestrian and bicycle through movement. While this more permeable version can be applied in new developments easily, modifying existing impermeable cul-de-sac streets is problematic as it encounters property ownership issues. Efforts in this direction are, however, being made. Given the complicated legal process and the sheer number of exiting cul-de-sac streets, however, such efforts would be slow to produce results and may only have a marginal impact in changing the landscape of existing districts. Conversely, transforming existing streets that are part of a grid plan into permeable, linked culs-de-sac, as was done in Berkeley, California and Vancouver, BC, is physically and administratively easy due to the public ownership of the street right-of-way. However, residents on adjacent through roads may resent the potential traffic increase and delay the process.
Increases in pedestrian and bicycle permeability may result in a displacement of local car trips for short distance destinations and consequently a reduction in neighbourhood vehicle emissions. The impermeable cul-de-sac not only discourages walking and biking but also increases the length of car trips by the circuitous geometry of the dendrite network structure of which it is a part. Research studies examined the influence of several variables on the amount of car travel that residents of several types of districts recorded. Results vary considerably among one other, but there is general agreement on a number of key correlations: a)The wealthier and the larger the family is the more cars they own and the more they drive, b)The farther away a family lives from the city centre and the fewer the jobs in the vicinity plus a slow bus service the more they drive and c)Street patterns may add a 10% length to local trips but the total VKTs are affected more by the "macro" urban than the "micro" neighbourhood structure.
Culs-de-sac, especially those that also cut off pedestrian connections instead of limiting only road traffic, have also been criticised for negative effects on safety, because they decrease the amount of through traffic (vehicular or pedestrian) that might spot an accident or crime victim in need of help. Proponents of culs-de-sac and gated communities have in turn countered that the reduction in through traffic makes any "stranger" much more recognisable in the closed local environment and thus reduces crime danger. This view has in turn been characterized as unrealistic; it is argued that since only a very small proportion of all non-locals passing through the area are potential criminals, increased traffic should increase rather than decrease safety.
New research has expanded the discussion on this disputed issue. A recent study did extensive spatial analysis and correlated several building, site plan and social factors with crime frequencies and identified subtle nuances to the contrasting positions. The study looked at, among others, a) dwelling types, b) unit density (site density) c) movement on the street, d) culs–de-sac or grids and e) the permeability of a residential area. Among its conclusions are, respectively, that a) flats are always safer than houses and the wealth of inhabitants matters; b) density is generally beneficial but more so at ground level; c) local movement is beneficial, larger scale movement not so; d) relative affluence and the number of neighbours has a greater effect than either being on a cul-de-sac or being on a through street. It also re-established that simple, linear culs-de-sac with good numbers of dwellings that are joined to through streets tend to be safe. As for permeability, it suggests that residential areas should be permeable enough to allow movement in all directions but no more. The over-provision of poorly used permeability is a crime hazard.
More generally, the New Urbanism
movement has offered criticism of the cul-de-sac and crescent (loop) street types not intended to network with each other. It has been suggested that such street layouts can cause increased traffic on the collector streets. It is recognized that cul-de-sac and looped streets inherently remove car traffic through them and restrict access to residents only. Resident traffic is naturally channelled to minor residential collectors and to arterials that provide inter-neighbourhood and inter-district connectivity. A study, reported in 1990, compared the traffic performance in a 700 acres (2.8 km²) development that was laid out using two approaches, one with and the other without hierarchy or cul-de-sac streets. It concluded that the non-hierarchical, traditional layout generally shows lower peak speed and shorter, more frequent intersection delays than the hierarchical pattern. The traditional pattern is not as friendly to the long trips as the hierarchical but friendlier to short trips. Local trips in it are shorter in distance but about equivalent in time with the hierarchical layout. A later similar comparative traffic study of about 830 acres (3.4 km²) oconcluded that all types of layouts perform adequately in most land use scenarios and that a refined hierarchical, dendrite network can improve traffic performance.
Anecdotal and research evidence suggests that navigation (especially on foot) in a disconnected network of cul-de-sac and looped streets is inconvenient and non-intuitive, particularly when combined with curvilinear geometry. Loss of orientation and sense of direction is also a common experience in older cities with cul-de-sac streets (Medina of Arab cities or Mediterranean hill towns) as well as in cities with highly irregular block geometries and sizes and corresponding street alignments that produce a labyrinthine effect. The long history of such cities implies that an irregular, complicated street network that appears entirely illegible to a visitor is well understood and used by the inhabitants. More convincing about its workability for their permanent residents are the case histories of cities such as Regensburg that show a gradual transformation of an imported or imposed orthogonal, “legible” grid to the traditional “confusing” street networks.
Cul-de-sac and loop streets can reduce the size of any given neighbourhood to a single street. Neighbourhoods can be defined by geographic boundaries but more often it is shared ethnic, socio-economic and cultural characteristics that create social cohesion irrespective of apparent physical "boundaries". Mehaffy et al. (2010), who propose a model for structuring an urban network, suggest that neighbourhoods cannot be designed into being. “Community” is viewed as a dynamic social and cultural construct especially in contemporary, open, multicultural cities. Residential area street configuration can only assist its emergence by reducing through traffic and increasing local pedestrian movement; a design goal for which connected cul-de-sac and looped streets are suited.
Issues of pedestrian trip length and isolation are sharply evident in the back-to-front housing arrangement where the front of the house fronts onto the cul-de-sac street while the rear fronts onto the main roads. Some of these problems can be mitigated by the newer practice of connecting the neighbouring roads and culs-de-sac with public pedestrian/cycle paths. In effect, this removes the discontinuity aspect for these modes of transport. Built examples of such connected culs-de-sac can be found in the United States
(such as Radburn
, New Jersey
and Village Homes
, California
), England
(such as Milton Keynes
) and Greece
(such as Papagou
, a suburb of Athens
) (see photo). A new system for organizing connected culs-de-sac, the Fused Grid
, has been developed by Canada Mortgage and Housing Corporation
.
In the North America
n development context and planning literature, cul-de-sac streets have been associated with low density residential development which is judged as inefficient by sustainable development
theorists and proponents. The increased prevalence of cul-de-sac streets occurred in the 1960s and '70s, a period of rapid economic and city expansion, when a detached house on a large lot meant an ideal form of habitation; overlooking the potential negative externalities. This temporal coincidence of the wide adoption of a street type and an increasing demand for large lots and houses creates the impression of a necessary relationship between street type and unit density. Historically, however, the earliest systematic application of the cul-de-sac street type by Raymond Unwin (1909) had a unit density between 8 and 12 units per acre, considerably higher than mid-to-late 20th century. Even early 21st century developments rarely achieve densities above 5 to 7 units per acre in the suburbs. Conversely, early 1950s suburban developments that were laid out on a grid exhibit similar low densities. Evidently, street, network type and density are not linked causally; other factors, such as land scarcity and income influence the outcome as, for example, in cities that are landlocked or that have low average incomes.
Another concern is often raised by emergency services, who can have difficulty locating streets when a community consists of a large number of similarly named culs-de-sac; also, large fire response vehicles, in particular, can have great difficulty with turning around in a cul-de-sac. However, confusing street naming is not a necessary outcome of street network design and can be improved. The practice of naming orthogonal networks by numbers and letters in the corresponding cardinal directions has been criticized by Camilo Sitte as lacking imagination. Nonetheless, police and fire departments now use advanced GPS
systems that quickly locate the destination and the shortest path to follow.
School buses can also have a hard time turning around, which means that children who live in a cul-de-sac must often walk to a bus stop on a main through road. However, recent research on obesity and urban planning suggests that this may be an advantage because it enables children to get daily physical activity. Longer walking distances, however, reduces interest to use buses especially when a car is available. This disincentive to walking to the school bus stop can be overcome in planned cul-de-sac streets by regulating their maximum length to about 500 ft (152.4 m), as was recommended and practiced by R. Unwin and others.
Weighing available evidence, has lead a few U.S. cities including Austin, Texas
; Charlotte, North Carolina
; and Portland, Oregon
to restrict and regulate the inclusion of cul-de-sac streets in new suburbs. However, a 2010 study on Spawl in NA by a legal expert concludes that “....neighborhoods dominated by cul-de-sacs are less walkable than those that include street grids...’. ‘On the other hand, cul-de-sacs do have a countervailing public benefit: because of their very inaccessibility, they tend to have less automobile traffic. Given the existence of important public policy goals on both sides, a city seeking to maximize walkability should not favor cul-de-sacs over grids, but should also allow some cul-de-sacs as a legitimate residential option’ ... ‘In addition, there are “middle ground” alternatives between prohibiting cul-de-sacs and mandating them. For example, a city could encourage cul-de-sacs combined with pedestrian walkways”. This design combination is shown in the Village Homes layout and is an integral part of the Fused Grid
.
wrote in his 1946 article, "Politics and the English Language
", that the term "cul de sac" is another foreign word used in English as pretentious diction, and is unnecessary.
The word "cul-de-sac" and its variants, "dead end" and "no exit", have inspired metaphorical uses in literature and in culture, often with the result that a word or phrase seeming to have a negative connotation is replaced in street signs. ("No outlet" is another alternative name used on street signs.)
Despite seeming to be a borrowed French phrase, the expression cul-de-sac originated in England during the period when French was spoken by the English
aristocracy
. (In modern French pronunciation, the is silent.) In Catalan
or in Occitan, "cul-de-sac" literally means "bottom of a bag". J. R. R. Tolkien
used the name Bag End as a literal translation of "cul-de-sac", to poke fun at the British use of French terms.
Some roadsigns in France also bear the additional inscription voie sans issue (literally "way without exit").
The word "cul-de-sac", referring to a dead end, is used informally in Europe (rarely officially since it is a mild profanity, cul also referring to the buttocks). In French-speaking Canada, the word "cul-de-sac" is used on signage.
Street naming conventions use the word impasse.
Diderot, in Jacques the Fatalist, uses the phrase impasse à la voltaire referring to the fact that Voltaire
considered cul-de-sac as really rude and advised to use impasse instead:
In the Canadian
province of Quebec
, a small green sign reading "cul-de-sac" is preferred. In bilingual regions of Canada, such as the Ottawa
metropolitan area, the term "pas de sortie" is preferred.
In Canada, "no exit" is prevalent, with the exception of Newfoundland, where "Cul-de-Sac" is in far more common use. The phrase, "No Exit", is also preferred for Chicago
signs, although "dead end" is still used there. In the UK, street signs more often display "cul-de-sac" rather than an English translation, or "no through road". U.S. Federal Highway Administration
rules state: "The Dead End sign may be used at the entrance of a single road or street that terminates in a dead end or cul-de-sac. The No Outlet sign may be used at the entrance to a road or road network from which there is no other exit." There is no federal regulation on "no exit".
Culs-de-sac may also be called "no through roads", especially in Australia where they are signposted as "No Through Road".
equivalent is "strupceļš" ("stumpy road"), rarely "ceļa gals" ("end of the road").
has favored "dead end" since at least the 1930s, when Sidney Kingsley
used the phrase to title his Broadway play about poor, tough East Side
youths with lives of little promise, in contrast to the dead-end streets of the nearby Sutton Place
neighborhood. (Similarly, French existentialist
Jean-Paul Sartre
titled a play about three damned sinners, Huis Clos, translated into English as "No Exit
".) Kingsley's play, later made into a movie, Dead End
, which proved so popular that it spawned similar movies, many starring a group of recurring characters known as the Dead End Kids
. The play and movies created such a strong image of bleak futures and an unfair society that some municipalities changed the sign terminology for culs-de-sac, often to "no outlet" or "no exit". (The "dead end" signs currently at Sutton Place are bright yellow with black lettering.)
In New York City, as of 2008, there were 4,659 "dead end" traffic signs, along with 160 "no outlet" signs. The city records, which go back to the 1960s, show only a couple "no exit" signs once existing near the approaches to the Midtown Tunnel, and which are no longer there. "We hear that some towns use 'no outlet' instead of 'dead end' because they think it sounds less morbid", New York City Commissioner of Transportation Janette Sadik-Khan
said in 2008. "We tell New Yorkers the truth: it's a 'dead end', and we think that motorists get the point quickly."
In some parts of England it is also thought to have originated from when coal was left at the end of small roads, literally meaning "coal-in-the-sack".
French language
French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...
) is a word of French origin referring to a dead end, close, no through road (British English
British English
British English, or English , is the broad term used to distinguish the forms of the English language used in the United Kingdom from forms used elsewhere...
) or court (American
American English
American English is a set of dialects of the English language used mostly in the United States. Approximately two-thirds of the world's native speakers of English live in the United States....
, Canadian
Canadian English
Canadian English is the variety of English spoken in Canada. English is the first language, or "mother tongue", of approximately 24 million Canadians , and more than 28 million are fluent in the language...
and Australian English
Australian English
Australian English is the name given to the group of dialects spoken in Australia that form a major variety of the English language....
) meaning dead-end street with only one inlet/outlet. While historically built for other reasons, one of its modern uses is to calm vehicle traffic
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...
.
History
Culs-de-sac have appeared in plans of towns and cities before the automotive 20th century, particularly in Arab and Moorish towns.The earliest example of cul-de-sac streets was unearthed in the El-Lahun
El-Lahun
Located in the Faiyum, Egypt, el-Lahun or Kahun is the workers' village associated with the pyramid of Senusret II . It is located near the modern village of el-Lahun , and is often known by that name...
workers village in Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
, which was built circa 1885 BCE. The village is laid out with straight streets that intersect at right angles; akin to a grid, but irregular. The western part of the excavated village, where the workers lived, shows fifteen narrow and short dead-end streets laid out perpendicularly on either side of a wider, straight street; all terminate at the enclosing walls.
In the UK, their prior existence is implied by an 1875 law which banned their use in new developments.
Inferential evidence of their earlier use can also be drawn from the text of a German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
architect, Rudolf Eberstadt, that explains their purpose and utility: “We have, in our medieval towns, examples of the old non-traffic street, showing very commendable methods of cutting up the land. I ought to mention here that to keep traffic out of residential streets is necessary not only in the general interest of the population, but, above all, for the sake of the children, whose health (amongst the working class
Working class
Working class is a term used in the social sciences and in ordinary conversation to describe those employed in lower tier jobs , often extending to those in unemployment or otherwise possessing below-average incomes...
es) is mainly dependent on the opportunity of moving about in close connection with their dwelling places, without the danger of being run over. In the earlier periods, traffic was excluded from residential streets simply by gates or by employing the cul-de-sac”.
It was in the UK that the cul-de-sac street type was first legislated into use, with “The Hampstead Garden Suburb Act, 1906”. The proponents of the Act, Raymond Unwin
Raymond Unwin
Sir Raymond Unwin was a prominent and influential English engineer, architect and town planner, with an emphasis on improvements in working class housing.-Early years:...
and Barry Parker, thus gained permission to introduce culs-de-sac in their subsequent site plans, and they promoted it as a suitable street type for Garden Suburbs. Unwin's applications of the cul-de-sac and the related crescent always included pedestrian paths independent of the road network. This design feature reflects the predominance of pedestrian movement for local trips at the turn of the 20th century, and presages the current planning priority for increased pedestrian accessibility. The 1906 Act defined the nature of the cul-de-sac as a non-through road and restricted its length to 500 feet (152.4 m). Garden cities
Garden City
- Places :Australia:*Toowoomba, Queensland, nicknamed "Garden City"*Garden City, a locality within Port Melbourne, Victoria* Westfield Garden City, a Westfield shopping centre in Upper Mount Gravatt, Brisbane...
in the UK that followed Hampstead, such as Welwyn Garden City
Welwyn Garden City
-Economy:Ever since its inception as garden city, Welwyn Garden City has attracted a strong commercial base with several designated employment areas. Among the companies trading in the town are:*Air Link Systems*Baxter*British Lead Mills*Carl Zeiss...
all included culs-de-sac (see photo).
In the 1920s, the garden city movement gained ground in the US and, with it, came its design elements, such as the cul-de-sac. Clarence Stein
Clarence Stein
Clarence Samuel Stein was an American urban planner, architect, and writer, a major proponent of the "Garden City" movement in the United States.- Biography :...
, a main proponent of the movement, incorporated it in the Radburn, NJ subdivision, which was to become a model for subsequent neighbourhood developments. The US Federal Housing Authority recommended and promoted their use through their 1936 guidelines and the power of lending development funds.
In Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, a variation of Stein’s Radburn 1929 plan that used crescents (loops) instead of culs-de-sac was built in 1947 in Winnipeg
Winnipeg
Winnipeg is the capital and largest city of Manitoba, Canada, and is the primary municipality of the Winnipeg Capital Region, with more than half of Manitoba's population. It is located near the longitudinal centre of North America, at the confluence of the Red and Assiniboine Rivers .The name...
, Manitoba Wildwood Park, designed by Hubert Bird. In 1954, the Central Mortgage and Housing Corporation published its own guidelines in which the cul-de-sac was strongly recommended for local streets and, as the FHA in the US, used its lending power to see its inclusion in development plans. The Varsity Village and Braeside, subdivisions in Calgary
Calgary
Calgary is a city in the Province of Alberta, Canada. It is located in the south of the province, in an area of foothills and prairie, approximately east of the front ranges of the Canadian Rockies...
, Alberta
Alberta
Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...
also used the Radburn model in the late 1960s.
In the 1960s the cul-de-sac attained systematic international application in planned new cities such as Doxiadis’ Islamabad
Islamabad
Islamabad is the capital of Pakistan and the tenth largest city in the country. Located within the Islamabad Capital Territory , the population of the city has grown from 100,000 in 1951 to 1.7 million in 2011...
(1960). In the UK new towns such as Harlow
Harlow
Harlow is a new town and local government district in Essex, England. It is located in the west of the county and on the border with Hertfordshire, on the Stort Valley, The town is near the M11 motorway and forms part of the London commuter belt.The district has a current population of 78,889...
(1947) by Sir Frederick Gibberd and Milton Keynes
Milton Keynes
Milton Keynes , sometimes abbreviated MK, is a large town in Buckinghamshire, in the south east of England, about north-west of London. It is the administrative centre of the Borough of Milton Keynes...
(1967) incorporated culs-de-sac and crescents in their layouts.
Planning theorists also advocated the use of culs-de-sac and crescents most notably, Christopher Alexander, in his “A Pattern Language
A Pattern Language
A Pattern Language: Towns, Buildings, Construction is a 1977 book on architecture, urban design, and community livability. It was authored by Christopher Alexander, Sara Ishikawa and Murray Silverstein of the Center for Environmental Structure of Berkeley, California, with writing credits also to...
” 1977 book (pattern #49). Doxiadis also argued their important role in separating man from machine.
Unplanned culs-de-sac
Virtual, unplanned culs-de-sac have appeared in the centers of cities which are laid on a grid. Whole neighbourhood street reconfigurations emerged in several cities including Berkeley CA, Seattle WA and Vancouver BC. This transformation of sections of the grid plan
Grid plan
The grid plan, grid street plan or gridiron plan is a type of city plan in which streets run at right angles to each other, forming a grid...
since the 1970s has occurred in response to the need for the following:
- limiting access to an existing but newly designated road as a major arterial and enable traffic to move smoothly on it and
- protecting neighborhood residents, particularly children, from the dangers of traffic and for alleviating residents' concerns (see picture)
This selective, sporadic transformation continues into the 21st century. As traffic volumes increase and as cities decide to remove or reduce traffic on specific streets of central areas, streets are closed off using bollards or landscaping thus creating new, unplanned cul-de-sac streets and produce a new, functional blend of the inherited grid with newer street types. A recent variation of limiting traffic is the managed closure by using retractable bollards which are activated by designated card holders only.
Function
In urban planningUrban planning
Urban planning incorporates areas such as economics, design, ecology, sociology, geography, law, political science, and statistics to guide and ensure the orderly development of settlements and communities....
culs-de-sac are created to limit through-traffic in residential areas. While some cul-de-sac streets provide no possible passage except in and out of their road entry, others allow cyclists, pedestrian
Pedestrian
A pedestrian is a person traveling on foot, whether walking or running. In some communities, those traveling using roller skates or skateboards are also considered to be pedestrians. In modern times, the term mostly refers to someone walking on a road or footpath, but this was not the case...
s or other non-automotive traffic to pass through connecting easements or paths.
This design improvement, which selectively excludes one mode of transport while permitting others, can be viewed as an example of “filtered permeability
Permeability (spatial and transport planning)
Permeability or connectivity describes the extent to which urban forms permit movement of people or vehicles in different directions. The terms are often used interchangeably, although differentiated definitions also exist...
”. Its application retains the cul-de-sac’s primary function as a non-through road, but establishes complete pedestrian and bicycle network connectivity.
In traffic engineering
Traffic engineering (transportation)
For the engineering of communications and computer networks, see Teletraffic engineering.Traffic engineering is a branch of civil engineering that uses engineering techniques to achieve the safe and efficient movement of people and goods on roadways...
parlance, the cul-de-sac defines the local street as having primarily an 'access' (to properties) function rather than as one having a 'transport' or 'through' function.
Suburban use and benefits
Since the end of World War IIWorld War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, new subdivisions
Subdivision (land)
Subdivision is the act of dividing land into pieces that are easier to sell or otherwise develop, usually via a plat. The former single piece as a whole is then known in the United States as a subdivision...
in the United States and Canada, as well as New Towns in England and other countries have made extensive use of the cul-de-sac and crescent (loops) street types. Typically, there is one or several central roads in the subdivision with many cul-de-sac streets of varying length, branching out from the main roads, to fill the land in the subdivision; a dendrite or hierarchical
Hierarchy of roads
The hierarchy of roads categorizes roads according to their functions and capacities. While sources differ on the exact nomenclature, the basic hierarchy comprises freeways, arterials, collectors, and local roads....
pattern. Since the 1960s, this pattern has been the dominant road network structure of suburbs and exurbs in the United States, Canada, and Australia. It is also increasingly popular in Latin America
Latin America
Latin America is a region of the Americas where Romance languages – particularly Spanish and Portuguese, and variably French – are primarily spoken. Latin America has an area of approximately 21,069,500 km² , almost 3.9% of the Earth's surface or 14.1% of its land surface area...
, Western Europe
Western Europe
Western Europe is a loose term for the collection of countries in the western most region of the European continents, though this definition is context-dependent and carries cultural and political connotations. One definition describes Western Europe as a geographic entity—the region lying in the...
, and China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
. In this pattern, there are only a few roads (relative to the number of cul-de-sac streets) leading out of the subdivision and into other subdivisions or onto major roads.
In the US, these changes can be attributed to real-estate developers' desire to meet FHA
Federal Housing Administration
The Federal Housing Administration is a United States government agency created as part of the National Housing Act of 1934. It insured loans made by banks and other private lenders for home building and home buying...
guidelines and make federal home loans available to their consumers. In Canada a similar incentive was provided to developers by CMHC
Canada Mortgage and Housing Corporation
Canada Mortgage and Housing Corporation is a Crown corporation, owned by the Government of Canada, founded after World War II to provide housing for returning soldiers...
. These incentives, which were discontinued in the 70s, gave the initial impetus for the application of the hierarchical pattern. In other countries such incentives do not exist and its adoption is motivated by consumer preferences.
Nineteenth and early 20th century American urban planning
Urban planning
Urban planning incorporates areas such as economics, design, ecology, sociology, geography, law, political science, and statistics to guide and ensure the orderly development of settlements and communities....
, emphasized a grid plan
Grid plan
The grid plan, grid street plan or gridiron plan is a type of city plan in which streets run at right angles to each other, forming a grid...
, partly out of extensive reliance on foot, horse and streetcars for transportation. In such earlier urban development, alleys were included to allow for deliveries of soiled supplies, such as coal, to the rear of houses which are now heated by electricity, piped natural gas or oil.
The use of culs-de-sac reduces the amount of car traffic on residential streets within the subdivision, thus reducing noise, air pollution and the probability of accidents. Ben-Joseph (1995) and Lovegrove/Sayed (2006) indicate a substantially lower collision rate for street networks based on the cul-de-sac street type. Dumbaugh and Rae (2009) suggest that land use patterns play a significant role in traffic safety and should be considered in conjunction with the network pattern. While all intersection types in general reduce the incidence of fatal crashes, four-way intersections, which rarely occur in a network with cul-de-sac or loop streets, increase total and injurious crashes significantly. The study recommends hybrid street networks with dense concentrations of T-intersections and concludes that a return to the 19th century gridiron is undesirable.
This decrease in traffic, in turn, is thought to lower the incidence of crime and increase desirability, because in most cases the people who traverse the cul-de-sac either live there or are guests of those who do. CPTED planning principles suggest increased natural surveillance and sense of ownership as a means of fostering security in a neighbourhood. Both of these phenomena occur naturally on a cul-de-sac street as does social networking. Design guidelines based on the CPTED perspective recommend its use for these reasons.
Cul-de-sac streets increase spontaneous outdoor activity by children. A study in California examined the amount of child play that occurred on the streets of neighbourhoods with different characteristics; grid pattern and culs-de-sac. The findings indicate that culs-de-sac showed substantial increase in play activity than the open grid street pattern. Culs-de-sac reduce perceived danger from traffic thereby encouraging more outdoor play.
Similar studies in Europe and Australia found that children’s outdoor play is significantly reduced on through roads where traffic is, or perceived by parents to be, a risk. In addition, they confirmed the results of the seminal Donald Appleyard
Donald Appleyard
Donald Appleyard was an urban designer and theorist, teaching at the University of California, Berkeley.Born in England, Appleyard studied first architecture, and later urban planning at the Massachusetts Institute of Technology. After graduation he taught at MIT for six years,and later at Berkley...
1982 study which showed the negative correlation between amount of traffic and social networks. These studies recommend the use of the cul-de-sac or strong traffic calming measures. When culs-de-sac are interconnected with foot and bike paths, as for example in Vauban, Freiburg
Vauban, Freiburg
Vauban is a new neighborhood of 5,000 inhabitants and 600 jobs 4 km to the south of the town center in Freiburg, Germany. It was built as "a sustainable model district" on the site of a former French military base, and is named after Sébastien Le Prestre de Vauban, the 17th century French...
, Village Homes
Village Homes
Village Homes is a planned community in Davis, California, designed to be ecologically sustainable. The more than 200 houses in the development utilize solar panels for heating, and are oriented around common areas at the rear of the buildings, rather than around the street at the front...
, Davis, California, they can increase active modes of mobility among their residents.
Real estate developers prefer culs-de-sac because they allow builders to fit more houses into oddly shaped tracts of land and facilitate building to the edges of rivers and property lines. They also choose these discontinuous network patterns of cul-de-sac and loop streets because of the often significant economies in infrastructure costs compared to the grid plan
Grid plan
The grid plan, grid street plan or gridiron plan is a type of city plan in which streets run at right angles to each other, forming a grid...
.
From an environmental perspective, culs-de-sac allow greater flexibility than the common grid in adapting to the natural grades of a site and to its ecologically sensitive features, such as streams creeks and mature forest growth.
The desirability of the cul-de-sac street type among home buyers is implied by the evidence that they often pay up to a 20% premium for a home on such a street, according to one study. This could be because there is considerably less passing traffic, resulting in less noise and reduced actual or perceived risk, increasing the sense of tranquility. A survey of residents on three types of streets: cul-de-sac, loop, and through (grid) recorded their preferences among these types. It found that 82% of cul-de-sac residents preferred their own street type, 18% preferred a loop, and 0% the grid. Only 13% of grid street residents preferred their own type and 54% would choose a cul-de-sac to live on.
Two other studies, reported in 1990 and 2009 respectively, confirmed this upward trend and determined the premium that cul-de-sac streets command. The first found a 29% premium over the streets in a grid. The second, focused on trails and greenbelts, found that other amenities including cul-de-sac streets add significantly to the home value.
The positive feelings that a cul-de-sac street could evoke, that residents value, are expressed vividly by Allan Jacobs
Allan Jacobs
Allan B. Jacobs is an urban designer, renowned for his publications and research on urban design. His well-known paper "Towards an Urban Design Manifesto", written with Donald Appleyard, describes how cities should be laid out....
in describing a short (250 ft), narrow (60 ft), and densely built (14 du/acre) cul-de-sac in the Shadyside
Shadyside
Shadyside may refer to:in the United States:* Shadyside, Indiana, site of head-on collision on railroad at passing loop* Shadyside, Ohio in Belmont County, Ohio* Shadyside , listed on the NRHP in Mississippi...
neighborhood of Pittsburgh, Pennsylvania: “Step into Roslyn Place and you are likely to sense, immediately, that you are in a place, a special place, a handsome place, a safe place, a welcoming place, a place where you might wish to live.” ... “narrowness and enclosure and intimacy bring a feeling of safety to Roslyn Place... “Stay on our street” is all the kids have to know.”
Gated communities
Gated community
In its modern form, a gated community is a form of residential community or housing estate containing strictly-controlled entrances for pedestrians, bicycles, and automobiles, and often characterized by a closed perimeter of walls and fences. Gated communities usually consist of small residential...
, steadily increasing worldwide, employ cul-de-sac and loop street networks because, having a dendrite structure, they reduce the number of through roads and, consequently, the corresponding number of entries and exits to be controlled.
Criticisms and discussion
Culs-de-sac are criticised by urban designers like those of the Foundation for the Built Environment in the United Kingdom for encouraging car transport for even short distances, as more direct connections are precluded by the dead-end geometry, which necessitates long travel distances even to physically nearby locations. This increases fuel consumption and vehicle emissions and has negative effects on health by reducing walking and cycling rates. Related research in the United States by Richard Jackson has shown that people in car-based (cul-de-sac heavy) communities weigh on average 6 lb (2.7 kg) more than those in traditional towns (with open grid networks).An extensive analysis of the research evidence by TRB,
however, shows only an association between the built environment and physical activity levels, not causal connections. The evidence does not either identify with certainty which characteristics of the built environment are most closely associated with physical activity behaviour. The study also warns against confusing inadequate physical activity with obesity which is the outcome of an energy imbalance. Many contemporary lifestyle trends some inevitable (sedentary work) and some avoidable, (frequent energy-rich food consumption or TV watching [4 h/d]), contribute to this imbalance and must be considered in understanding and combating obesity
Obesity
Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...
.
The imperemability deficiency of the typical cul-de-sac street can be addressed by applying a modified, improved version of it, mentioned above, that enables pedestrian and bicycle through movement. While this more permeable version can be applied in new developments easily, modifying existing impermeable cul-de-sac streets is problematic as it encounters property ownership issues. Efforts in this direction are, however, being made. Given the complicated legal process and the sheer number of exiting cul-de-sac streets, however, such efforts would be slow to produce results and may only have a marginal impact in changing the landscape of existing districts. Conversely, transforming existing streets that are part of a grid plan into permeable, linked culs-de-sac, as was done in Berkeley, California and Vancouver, BC, is physically and administratively easy due to the public ownership of the street right-of-way. However, residents on adjacent through roads may resent the potential traffic increase and delay the process.
Increases in pedestrian and bicycle permeability may result in a displacement of local car trips for short distance destinations and consequently a reduction in neighbourhood vehicle emissions. The impermeable cul-de-sac not only discourages walking and biking but also increases the length of car trips by the circuitous geometry of the dendrite network structure of which it is a part. Research studies examined the influence of several variables on the amount of car travel that residents of several types of districts recorded. Results vary considerably among one other, but there is general agreement on a number of key correlations: a)The wealthier and the larger the family is the more cars they own and the more they drive, b)The farther away a family lives from the city centre and the fewer the jobs in the vicinity plus a slow bus service the more they drive and c)Street patterns may add a 10% length to local trips but the total VKTs are affected more by the "macro" urban than the "micro" neighbourhood structure.
Culs-de-sac, especially those that also cut off pedestrian connections instead of limiting only road traffic, have also been criticised for negative effects on safety, because they decrease the amount of through traffic (vehicular or pedestrian) that might spot an accident or crime victim in need of help. Proponents of culs-de-sac and gated communities have in turn countered that the reduction in through traffic makes any "stranger" much more recognisable in the closed local environment and thus reduces crime danger. This view has in turn been characterized as unrealistic; it is argued that since only a very small proportion of all non-locals passing through the area are potential criminals, increased traffic should increase rather than decrease safety.
New research has expanded the discussion on this disputed issue. A recent study did extensive spatial analysis and correlated several building, site plan and social factors with crime frequencies and identified subtle nuances to the contrasting positions. The study looked at, among others, a) dwelling types, b) unit density (site density) c) movement on the street, d) culs–de-sac or grids and e) the permeability of a residential area. Among its conclusions are, respectively, that a) flats are always safer than houses and the wealth of inhabitants matters; b) density is generally beneficial but more so at ground level; c) local movement is beneficial, larger scale movement not so; d) relative affluence and the number of neighbours has a greater effect than either being on a cul-de-sac or being on a through street. It also re-established that simple, linear culs-de-sac with good numbers of dwellings that are joined to through streets tend to be safe. As for permeability, it suggests that residential areas should be permeable enough to allow movement in all directions but no more. The over-provision of poorly used permeability is a crime hazard.
More generally, the New Urbanism
New urbanism
New Urbanism is an urban design movement, which promotes walkable neighborhoods that contain a range of housing and job types. It arose in the United States in the early 1980s, and has gradually continued to reform many aspects of real estate development, urban planning, and municipal land-use...
movement has offered criticism of the cul-de-sac and crescent (loop) street types not intended to network with each other. It has been suggested that such street layouts can cause increased traffic on the collector streets. It is recognized that cul-de-sac and looped streets inherently remove car traffic through them and restrict access to residents only. Resident traffic is naturally channelled to minor residential collectors and to arterials that provide inter-neighbourhood and inter-district connectivity. A study, reported in 1990, compared the traffic performance in a 700 acres (2.8 km²) development that was laid out using two approaches, one with and the other without hierarchy or cul-de-sac streets. It concluded that the non-hierarchical, traditional layout generally shows lower peak speed and shorter, more frequent intersection delays than the hierarchical pattern. The traditional pattern is not as friendly to the long trips as the hierarchical but friendlier to short trips. Local trips in it are shorter in distance but about equivalent in time with the hierarchical layout. A later similar comparative traffic study of about 830 acres (3.4 km²) oconcluded that all types of layouts perform adequately in most land use scenarios and that a refined hierarchical, dendrite network can improve traffic performance.
Anecdotal and research evidence suggests that navigation (especially on foot) in a disconnected network of cul-de-sac and looped streets is inconvenient and non-intuitive, particularly when combined with curvilinear geometry. Loss of orientation and sense of direction is also a common experience in older cities with cul-de-sac streets (Medina of Arab cities or Mediterranean hill towns) as well as in cities with highly irregular block geometries and sizes and corresponding street alignments that produce a labyrinthine effect. The long history of such cities implies that an irregular, complicated street network that appears entirely illegible to a visitor is well understood and used by the inhabitants. More convincing about its workability for their permanent residents are the case histories of cities such as Regensburg that show a gradual transformation of an imported or imposed orthogonal, “legible” grid to the traditional “confusing” street networks.
Cul-de-sac and loop streets can reduce the size of any given neighbourhood to a single street. Neighbourhoods can be defined by geographic boundaries but more often it is shared ethnic, socio-economic and cultural characteristics that create social cohesion irrespective of apparent physical "boundaries". Mehaffy et al. (2010), who propose a model for structuring an urban network, suggest that neighbourhoods cannot be designed into being. “Community” is viewed as a dynamic social and cultural construct especially in contemporary, open, multicultural cities. Residential area street configuration can only assist its emergence by reducing through traffic and increasing local pedestrian movement; a design goal for which connected cul-de-sac and looped streets are suited.
Issues of pedestrian trip length and isolation are sharply evident in the back-to-front housing arrangement where the front of the house fronts onto the cul-de-sac street while the rear fronts onto the main roads. Some of these problems can be mitigated by the newer practice of connecting the neighbouring roads and culs-de-sac with public pedestrian/cycle paths. In effect, this removes the discontinuity aspect for these modes of transport. Built examples of such connected culs-de-sac can be found in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
(such as Radburn
Radburn, New Jersey
Radburn is an unincorporated planned community located within Fair Lawn, in Bergen County, New Jersey, United States.Radburn was founded in 1929 as "a town for the motor age"...
, New Jersey
New Jersey
New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...
and Village Homes
Village Homes
Village Homes is a planned community in Davis, California, designed to be ecologically sustainable. The more than 200 houses in the development utilize solar panels for heating, and are oriented around common areas at the rear of the buildings, rather than around the street at the front...
, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
), England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
(such as Milton Keynes
Milton Keynes
Milton Keynes , sometimes abbreviated MK, is a large town in Buckinghamshire, in the south east of England, about north-west of London. It is the administrative centre of the Borough of Milton Keynes...
) and Greece
Greece
Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....
(such as Papagou
Papagou
Papagou is a suburb in the northeastern part of Athens, Greece. The city is named after Marshal Alexandros Papagos, a Greek Army General who served in the Second World War...
, a suburb of Athens
Athens
Athens , is the capital and largest city of Greece. Athens dominates the Attica region and is one of the world's oldest cities, as its recorded history spans around 3,400 years. Classical Athens was a powerful city-state...
) (see photo). A new system for organizing connected culs-de-sac, the Fused Grid
Fused Grid
The Fused Grid is a street network pattern first proposed in 2002 and subsequently applied in Calgary, Alberta and in Stratford, Ontario . It represents a synthesis of two well known and extensively used network concepts: the "grid" and the “Radburn” pattern, derivatives of which are found in most...
, has been developed by Canada Mortgage and Housing Corporation
Canada Mortgage and Housing Corporation
Canada Mortgage and Housing Corporation is a Crown corporation, owned by the Government of Canada, founded after World War II to provide housing for returning soldiers...
.
In the North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
n development context and planning literature, cul-de-sac streets have been associated with low density residential development which is judged as inefficient by sustainable development
Sustainable development
Sustainable development is a pattern of resource use, that aims to meet human needs while preserving the environment so that these needs can be met not only in the present, but also for generations to come...
theorists and proponents. The increased prevalence of cul-de-sac streets occurred in the 1960s and '70s, a period of rapid economic and city expansion, when a detached house on a large lot meant an ideal form of habitation; overlooking the potential negative externalities. This temporal coincidence of the wide adoption of a street type and an increasing demand for large lots and houses creates the impression of a necessary relationship between street type and unit density. Historically, however, the earliest systematic application of the cul-de-sac street type by Raymond Unwin (1909) had a unit density between 8 and 12 units per acre, considerably higher than mid-to-late 20th century. Even early 21st century developments rarely achieve densities above 5 to 7 units per acre in the suburbs. Conversely, early 1950s suburban developments that were laid out on a grid exhibit similar low densities. Evidently, street, network type and density are not linked causally; other factors, such as land scarcity and income influence the outcome as, for example, in cities that are landlocked or that have low average incomes.
Another concern is often raised by emergency services, who can have difficulty locating streets when a community consists of a large number of similarly named culs-de-sac; also, large fire response vehicles, in particular, can have great difficulty with turning around in a cul-de-sac. However, confusing street naming is not a necessary outcome of street network design and can be improved. The practice of naming orthogonal networks by numbers and letters in the corresponding cardinal directions has been criticized by Camilo Sitte as lacking imagination. Nonetheless, police and fire departments now use advanced GPS
GPS navigation device
A GPS navigation device is any device that receives Global Positioning System signals for the purpose of determining the device's current location on Earth...
systems that quickly locate the destination and the shortest path to follow.
School buses can also have a hard time turning around, which means that children who live in a cul-de-sac must often walk to a bus stop on a main through road. However, recent research on obesity and urban planning suggests that this may be an advantage because it enables children to get daily physical activity. Longer walking distances, however, reduces interest to use buses especially when a car is available. This disincentive to walking to the school bus stop can be overcome in planned cul-de-sac streets by regulating their maximum length to about 500 ft (152.4 m), as was recommended and practiced by R. Unwin and others.
Weighing available evidence, has lead a few U.S. cities including Austin, Texas
Austin, Texas
Austin is the capital city of the U.S. state of :Texas and the seat of Travis County. Located in Central Texas on the eastern edge of the American Southwest, it is the fourth-largest city in Texas and the 14th most populous city in the United States. It was the third-fastest-growing large city in...
; Charlotte, North Carolina
Charlotte, North Carolina
Charlotte is the largest city in the U.S. state of North Carolina and the seat of Mecklenburg County. In 2010, Charlotte's population according to the US Census Bureau was 731,424, making it the 17th largest city in the United States based on population. The Charlotte metropolitan area had a 2009...
; and Portland, Oregon
Portland, Oregon
Portland is a city located in the Pacific Northwest, near the confluence of the Willamette and Columbia rivers in the U.S. state of Oregon. As of the 2010 Census, it had a population of 583,776, making it the 29th most populous city in the United States...
to restrict and regulate the inclusion of cul-de-sac streets in new suburbs. However, a 2010 study on Spawl in NA by a legal expert concludes that “....neighborhoods dominated by cul-de-sacs are less walkable than those that include street grids...’. ‘On the other hand, cul-de-sacs do have a countervailing public benefit: because of their very inaccessibility, they tend to have less automobile traffic. Given the existence of important public policy goals on both sides, a city seeking to maximize walkability should not favor cul-de-sacs over grids, but should also allow some cul-de-sacs as a legitimate residential option’ ... ‘In addition, there are “middle ground” alternatives between prohibiting cul-de-sacs and mandating them. For example, a city could encourage cul-de-sacs combined with pedestrian walkways”. This design combination is shown in the Village Homes layout and is an integral part of the Fused Grid
Fused Grid
The Fused Grid is a street network pattern first proposed in 2002 and subsequently applied in Calgary, Alberta and in Stratford, Ontario . It represents a synthesis of two well known and extensively used network concepts: the "grid" and the “Radburn” pattern, derivatives of which are found in most...
.
Terminology
George OrwellGeorge Orwell
Eric Arthur Blair , better known by his pen name George Orwell, was an English author and journalist...
wrote in his 1946 article, "Politics and the English Language
Politics and the English Language
"Politics and the English Language" is an essay by George Orwell criticizing "ugly and inaccurate" contemporary written English.Orwell said that political prose was formed "to make lies sound truthful and murder respectable, and to give an appearance of solidity to pure wind." Orwell believed...
", that the term "cul de sac" is another foreign word used in English as pretentious diction, and is unnecessary.
The word "cul-de-sac" and its variants, "dead end" and "no exit", have inspired metaphorical uses in literature and in culture, often with the result that a word or phrase seeming to have a negative connotation is replaced in street signs. ("No outlet" is another alternative name used on street signs.)
Despite seeming to be a borrowed French phrase, the expression cul-de-sac originated in England during the period when French was spoken by the English
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
aristocracy
Aristocracy
Aristocracy , is a form of government in which a few elite citizens rule. The term derives from the Greek aristokratia, meaning "rule of the best". In origin in Ancient Greece, it was conceived of as rule by the best qualified citizens, and contrasted with monarchy...
. (In modern French pronunciation, the
Catalan language
Catalan is a Romance language, the national and only official language of Andorra and a co-official language in the Spanish autonomous communities of Catalonia, the Balearic Islands and Valencian Community, where it is known as Valencian , as well as in the city of Alghero, on the Italian island...
or in Occitan, "cul-de-sac" literally means "bottom of a bag". J. R. R. Tolkien
J. R. R. Tolkien
John Ronald Reuel Tolkien, CBE was an English writer, poet, philologist, and university professor, best known as the author of the classic high fantasy works The Hobbit, The Lord of the Rings, and The Silmarillion.Tolkien was Rawlinson and Bosworth Professor of Anglo-Saxon at Pembroke College,...
used the name Bag End as a literal translation of "cul-de-sac", to poke fun at the British use of French terms.
Spanish language
In Spanish, a cul-de-sac is called a "callejón sin salida" or 'calle privada' (literally, a "private street"), often shortened to a 'privada'. In Venezuela it is called "calle ciega" (blind street)Portuguese language
In Portuguese, a cul-de-sac is called a "beco sem saída" (literally, a "no-exit alley"). Despite the name, "becos sem saída" can vary very-small and narrow streets to wide avenues which have been cut off at one end due to newer developments. It is also shortened to "beco" often, even though a "beco" (alley) is not necessarily a cul-de-sac.Croatian language
In Croatia, a cul-de-sac is called 'slijepa ulica' (literally "blind street").Lithuanian language
In Lithuania, a cul-de-sac is called 'akligatvis' (literally "blind street").Dutch language
In The Netherlands, a cul-de-sac is called 'doodlopende weg' ('dead(ending) road') on traffic signs.French language
For signage, European countries use a graphic symbol somewhat like a "T" with a red top, rather than a sign with words.Some roadsigns in France also bear the additional inscription voie sans issue (literally "way without exit").
The word "cul-de-sac", referring to a dead end, is used informally in Europe (rarely officially since it is a mild profanity, cul also referring to the buttocks). In French-speaking Canada, the word "cul-de-sac" is used on signage.
Street naming conventions use the word impasse.
Diderot, in Jacques the Fatalist, uses the phrase impasse à la voltaire referring to the fact that Voltaire
Voltaire
François-Marie Arouet , better known by the pen name Voltaire , was a French Enlightenment writer, historian and philosopher famous for his wit and for his advocacy of civil liberties, including freedom of religion, free trade and separation of church and state...
considered cul-de-sac as really rude and advised to use impasse instead:
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In the Canadian
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
province of Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
, a small green sign reading "cul-de-sac" is preferred. In bilingual regions of Canada, such as the Ottawa
Ottawa
Ottawa is the capital of Canada, the second largest city in the Province of Ontario, and the fourth largest city in the country. The city is located on the south bank of the Ottawa River in the eastern portion of Southern Ontario...
metropolitan area, the term "pas de sortie" is preferred.
English language
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...
signs, although "dead end" is still used there. In the UK, street signs more often display "cul-de-sac" rather than an English translation, or "no through road". U.S. Federal Highway Administration
Federal Highway Administration
The Federal Highway Administration is a division of the United States Department of Transportation that specializes in highway transportation. The agency's major activities are grouped into two "programs," the Federal-aid Highway Program and the Federal Lands Highway Program...
rules state: "The Dead End sign may be used at the entrance of a single road or street that terminates in a dead end or cul-de-sac. The No Outlet sign may be used at the entrance to a road or road network from which there is no other exit." There is no federal regulation on "no exit".
Culs-de-sac may also be called "no through roads", especially in Australia where they are signposted as "No Through Road".
German language
In German-speaking countries, a cul-de-sac is called "Sackgasse". "Gasse" means alley/lane and "Sack" means bag, because a bag has one opening only.Danish language
A cul-de-sac is in Danish called "Blind vej". It basically means "Blind way / street".Indonesian language
The Indonesian equivalent to cul-de-sac is "Jalan Buntu". It basically means "no through road".Italian language
The Italian equivalent to cul-de-sac is "vicolo cieco", literally "blind alley".Russian language
The Russian equivalent to cul-de-sac is "Тупик". It basically means "no through road".Latvian language
The Latvian languageLatvian language
Latvian is the official state language of Latvia. It is also sometimes referred to as Lettish. There are about 1.4 million native Latvian speakers in Latvia and about 150,000 abroad. The Latvian language has a relatively large number of non-native speakers, atypical for a small language...
equivalent is "strupceļš" ("stumpy road"), rarely "ceļa gals" ("end of the road").
Polish language
The Polish language utilizes expression "ślepa ulica" (literally "blind street") or "sięgacz" (literally "something that reaches").Korean Language
The Korean equivalent to cul-de-sac is "막다른 길(Makdareun Gil)". It means "Blocked(막다르다) Road(길)".United States regional variants
New York CityNew 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...
has favored "dead end" since at least the 1930s, when Sidney Kingsley
Sidney Kingsley
Sidney Kingsley was an American dramatist. He received the Pulitzer Prize for Drama for his play Men in White in 1934.- Biography :...
used the phrase to title his Broadway play about poor, tough East Side
East Side (Manhattan)
The East Side of Manhattan refers to the side of Manhattan Island which abuts the East River and faces Brooklyn and Queens. Fifth Avenue, Central Park, and lower Broadway separate it from the West Side....
youths with lives of little promise, in contrast to the dead-end streets of the nearby Sutton Place
Sutton Place, Manhattan
Sutton Place is the name given to one of the most affluent streets in the borough of Manhattan in New York City, New York, United States, situated on the border between the Midtown and Upper East Side neighborhoods...
neighborhood. (Similarly, French existentialist
Existentialism
Existentialism is a term applied to a school of 19th- and 20th-century philosophers who, despite profound doctrinal differences, shared the belief that philosophical thinking begins with the human subject—not merely the thinking subject, but the acting, feeling, living human individual...
Jean-Paul Sartre
Jean-Paul Sartre
Jean-Paul Charles Aymard Sartre was a French existentialist philosopher, playwright, novelist, screenwriter, political activist, biographer, and literary critic. He was one of the leading figures in 20th century French philosophy, particularly Marxism, and was one of the key figures in literary...
titled a play about three damned sinners, Huis Clos, translated into English as "No Exit
No Exit
No Exit is a 1944 existentialist French play by Jean-Paul Sartre. The original French title is Huis Clos, the French equivalent of the legal term in camera, referring to a private discussion behind closed doors; English translations have also been performed under the titles In Camera, No Way Out...
".) Kingsley's play, later made into a movie, Dead End
Dead End
Dead End is a 1937 crime drama film. It is an adaptation of the Sidney Kingsley 1935 Broadway play of the same name. It stars Humphrey Bogart, Joel McCrea, and Sylvia Sidney...
, which proved so popular that it spawned similar movies, many starring a group of recurring characters known as the Dead End Kids
Dead End Kids
The Dead End Kids were a group of young actors from New York who appeared in Sidney Kingsley's Broadway play Dead End in 1935. In 1937 producer Samuel Goldwyn brought all of them to Hollywood and turned the play into a film...
. The play and movies created such a strong image of bleak futures and an unfair society that some municipalities changed the sign terminology for culs-de-sac, often to "no outlet" or "no exit". (The "dead end" signs currently at Sutton Place are bright yellow with black lettering.)
In New York City, as of 2008, there were 4,659 "dead end" traffic signs, along with 160 "no outlet" signs. The city records, which go back to the 1960s, show only a couple "no exit" signs once existing near the approaches to the Midtown Tunnel, and which are no longer there. "We hear that some towns use 'no outlet' instead of 'dead end' because they think it sounds less morbid", New York City Commissioner of Transportation Janette Sadik-Khan
Janette Sadik-Khan
Janette Sadik-Khan is the current Commissioner of the New York City Department of Transportation, appointed by New York City Mayor Michael Bloomberg on April 27, 2007, to replace Iris Weinshall....
said in 2008. "We tell New Yorkers the truth: it's a 'dead end', and we think that motorists get the point quickly."
Other uses
In military parlance, a "cul-de-sac" refers to a situation where an army is "hemmed in on all sides but behind" "Cul-de-sac" is also used metaphorically to mean a line of thought or action that leads nowhere.In some parts of England it is also thought to have originated from when coal was left at the end of small roads, literally meaning "coal-in-the-sack".