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Reference guide for urban road design
Suhas Kulhalli (firstname.lastname@example.org): Concept, Compilation and Editing
Adhiraj S Joglekar: Road layouts, standards
Ganesh Gaikwad (email@example.com): Signage
K.V Pathy: Bus-stops
R.N Kulhalli: Language
Pranav Jha, P.S. Anantharaman
praja.in: incubation, comments etc
Version Release Notes Release
1.0 Skeletal Draft. Basic structure of document. Section 1 to 4 complete. 5-Apr-09
Section 5, only two examples complete. Even here, figures and
pictures need to be added. Section 6,7,8 only idea is given. Document
not yet formatted.
1.1 Added some figures and minor edits 20-Apr-09
1.2 Added section on intersections, ongoing 01-Jun-09
1.3 Many sections added. Added an example template. Deleted the notes 01-Sep-09
section in appendix
1. Introduction................................................................................................................. 3
2. Objective ..................................................................................................................... 3
3. Approach..................................................................................................................... 6
4. Uses of streets ............................................................................................................. 8
4.1 People movement................................................................................................ 8
4.2 Static uses............................................................................................................ 8
4.3 Environmental functions..................................................................................... 8
4.4 Utility uses .......................................................................................................... 9
5. Requirements/specifications for each use................................................................. 10
5.1 People movement.............................................................................................. 10
5.2 Static uses.......................................................................................................... 31
5.3 Environmental functions................................................................................... 36
5.4 Utility uses ........................................................................................................ 37
6. Design example............................................................................................................. 38
7. Classification of Roads ................................................................................................. 38
8. Design templates for each road type............................................................................. 39
Glossary ............................................................................................................................ 42
Interesting links................................................................................................................. 44
Some useful dimensional information .............................................................................. 45
Streets are the arteries of urban communties. They are the ones which provide mobility for
men and material. They are also used for water, sewerage, telecom, electricity distribution
alike. They also to a large extent determine the character of the city. Well designed and
well maintained streets can make a perceptible difference to the quality of life.
In this document, we deal with streets in the urban and semi-urban context. Streets and
roads are used interchangeably to mean the same thing. When building a road, there are
different aspects which come into play. We can classify them as under
• Geometric design
Relating to the road layout, i.e. the plan view and section view from an engineering
drawing viewpoint. Thus, the width of pavement(vehicular portion), footpaths,
intersection design, position of streetlights, trees & street furniture, height of kerb etc
all come under this
• Construction and Maintaineance
Relating to the actual materials, quality of construction. Implementation of a given
geometric design would mostly fall in this classification.
These could be the actual tendering process, financials, systems for monitoring and
Our focus is going to be the geometric design aspect. The geometric design of streets
can make a huge difference how efficiently it carries out its functions, and its safety.
The general expectations from a street are listed below. In other words, these are the
principles/objectives on which street design should be based.
This is the primary concern. A road should be safe for all users, including and specially
pedestrians, cyclists, the elderly and the handicapped. In the absence of good designs and
enforcement, might is right rules, traffic can be chaotic and unsafe.
2. Ease of navigation
We frequently have faced situations when a parked car is abutting a road, or pedestrians
standing in the middle of the road causing the vehicle driver to swerve, or at U-turn with
cars piled up obstructing the straight moving traffic. All this results in the driver always on
the edge, and can never relax. This makes the whole driving experience a stressful one.
Similar is the case with pedestrians. With no clear cut footpath or pedestrian crossings at
intersections, it can be a very stressful experience just crossing a road, or even walking on
the footpath This need not be the case.
Ease of navigation can always be achieved, as against speed of navigation. Speed depends
on the road available and traffic. However, navigation, irrespective of traffic density, both
of pedestrians or vehicles can be made easier and stress free by better designs of roads and
3. Quick and smooth movement
Design should ensure quick and smooth movement of vehicles. This does not mean that
vehicles should go with high speed, rather that they can maintain a decent average speed
over their drive.
Pretty, Neat, Clean and Green.
Should be beautiful and beautiful roads is what makes the city look pretty.
Neat, with clearly marked lanes, straight footpath edges, no protrusions, are all required of
Cleanliness should be built in, that is, it should be easy to clean and maintain.
Roads present a wonderful opportunity to add to the green cover of the city. Trees and
other greenery along the roads can make it a very pleasant experience.
5. Optimal space utilization
To achieve all the above, we must keep in mind that space is at a premium in the urban
cities. All the above must be achieved within the given or reasonable width of road. To do
this one must design innovative and efficiently.
Thus the roads must be comprehensively designed to make efficient use of available space,
taking into account all its uses. Examples of some functions are street furniture such as bus-
stops, street lighting, utility lines such as electrical, water and drainage, cables etc.
What are the requirements/ specifications of each aspect of the road, so as to meet the
above objectives ? How does one approach the design to meet the above ? This are some of
the things this document is about and we will address these in the coming sections
. If nothing else, this should really get us focused on better road design. A
systematic approach as detailed in this document should result in better
designed roads, safer for everybody and resulting in lives saved. No effort is
too high if it results in saving of lives.
To get to a design which is comprehensive and looks at all aspects of the road, we go about
it in the following way.
First, we list all possible uses of a road. These include, but are not limited to vehicular (2,3
& 4 wheelers), cyclists, pedestrians, bus-stops and other street furniture such as streetlights,
electric lines, utility lines, drainage and sewerage, parking, hawkers etc. Make a
comprehensive checklist to make sure all possible utilizations are included.
Next, for each of these uses, we list down all the requirements. To come up with these
requirements, we need to place our selves in position of the user/utility provider and look at
what would be required to meet the above mentioned objective. In addition, one needs to
look at specifications and guidelines of the IRC (Indian Road congress) and equivalent
international standards. These will then be collated and organized in a systematic manner.
Once the requirements of each of the use cases has been obtained a detailed checklist needs
to be formed, which would incorporate all the requirements for all the uses. As one goes
through the process of road design, one should ensure at the end of it that the checklist is
gone through and all have been met.
It would be cumbersome to do this process for each road that comes up. Not only this, if we
come up with a different design each time, the lack of consistency will confuse road users
and lead to further accidents. Hence, it is imperative that this be standardized to some
extent. The way this can be done is to build a reference design. These essentially have the
plan view and section view of a typical road section. For any new road, this should be
Now obviously one reference design will not suffice for the variety of roads that are in use
in a city. For example, a residential road will look quite different from an arterial road.
Thus there is a need to make many such reference designs for a variety of roads. To do this,
roads should be categorized depending on their primary use and width. A reference design
should be then done for each of these road types. This becomes a template developed for
these type of roads, and one would have a template for each road type.
A similar approach and template designs are covered in IRC7. However, these reference
designs are not comprehensive, and are primarily done only to give the desired road width
Lastly, for this to have an impact city-wide, these templates should be mandatory part of
the road specifications and tendering process. If the road developed is given to a private
contractor, it should be ensured that the geometric design is specified and the given
template is adhered too. Over time, this will ensure all roads have a basic uniformity, as
well as are optimized to meet the local need and the broad objectives set out at the
beginning of the document.
4) Uses of streets
There is more to a street than movement of vehicles. It also needs to be safe, usable and
appealing for pedestrians, cyclists and handicapped. It is also used for parking, turns,
used by hawkers, etc. For better understanding we will classify and list these down.
4.1 People movement
4.1.1 Thoroughfare for motorized vehicles
3 & 4 wheelers, light commercial vehicles
Greater than 4 wheelers, heavy commercial vehicles.
4.1.2 Thoroughfare for non-motorized vehicles
4.1.3 Street intersections, turns and pedestrian crossings
Intersection types and additional requirements
4.2 Static uses
2 wheeler parking
4 wheeler parking
3 wheeler[rickshaw],Taxi and Para-transit parking
Heavy vehicles parking
4.2.3 Bus-stops and transit facilities
4.2.5 Hoardings/advertisement banners
4.3 Environmental functions
4.3.2 Garbage bins
4.3.3 Rain water run off
4.4 Utility uses
4.4.4 Telephone cables
4.4.5 Internet cables
4.4.6 Cable TV
5) Requirements/specifications for each use
Requirements of each use case will be listed comprehensively, taking inputs from multiple
sources. Were possible, the requirement will be specified numerically. The first source for
the requirements would be IRC documents. In case requisite IRC guidelines are unavailable
or insufficient, other national standards(primarily UK) are used.
5.1 People movement
5.1.1 Thoroughfare for motorized vehicles
3 & 4 wheelers, light commercial vehicles
Greater than 4 wheelers, heavy commercial vehicles.
5.1.2 Thoroughfare for non-motorized vehicles
1. Width of footpath [also called side-walk]
IRC guidelines1 stipulate that the minimum width of a footpath should not be less
than 1.5m. Width should depend on pedestrian traffic, varying between 1.5m at a
minimum to a maximum of 4.0m.
Pole with the cross-bar on the left, Bus-stop on the top right and Electric Box and
tree in the bottom rightpicture on the right obstruct the footpath and make it
ever, in addition to providing footpath for pedestrians, it is equally important to see
that this complete width is always available throughout the road and is
unobstructed. Frequently, we observe that the footpath is not clear, either because of
hawkers, parking, bus-stops etc. So part of providing a quality footpath is to provide
different spatial arrangements for these.
Whenever there is a constriction in the footpath, the person in order to skip it will
walk on the road. Then, even if a clear stretch of footpath is available, there is a
tendency to continue walking on the road. Also, a pole in the middle will halve the
space available for the wheelchair, and may make it unusable for the
Figure on the left shows how the footpath is obstructed by a tree and pole, causing
the pedestrian to avoid the footpath altogether. On the right, pole is on the edge
and trees are in a separate line outside the footpath, giving unobstructed space for
Hence, the footpath should be unobstructed throughout. To enable this, street
furniture such as electrical poles, lamp posts, trees etc should be placed one edge of
the footpath and not arbitrarily somewhere on the footpath. Similarly pole
transformers should be at such a height so as to not obstruct pedestrians.
Where absolutely unavoidable, in presence of localized obstructions, the
unobstructed width of a footpath should not be less than 1m to allow a
wheelchair(815mm) to pass comfortably. Overhangs if any should be at a height
greater than 3m from the footpath level.
Figure on the left shows how a tree obstructs the footpath, no clear parking space for car
and pedestrian walks right in the middle of the lane. On the right, trees planted
strategically, car nicely tucked in the middle, pedestrians get wide clear pretty footpath and
vehicle lanes are unobstructed. Everybody’s happy!
2. Kerb Height
The footpath would usually be at a slightly elevated height referred to the paved
road. This gives protection to the
pedestrians, prevents vehicles from
coming over to the footpath and
helps better segregation. Kerbs may be
provided at the road edge to increase this
segregation. The IRC2 recommends kerb
heights between 325mm to 200mm on
the road side with the footpath
elevation of 125mm with respect to
the paved road. A high kerb forces the car park away
However, we find that, this height is more than the clearance of vehicle doors
(~250mm, Ground clearance of Maruti 800, Hyundai Santro is 170mm). So in the
case of parallel parking, it becomes inconvenient to open the passenger side door of
the car. This results in the vehicle being parked at a distance from the kerb, thus
using valuable road space.
Hence, it is recommended that in case there is provision for parking adjacent to the
footpath, the additional kerb barrier be done away with. That is, the footpath is
maintained at an elevation of 125mm with respect to the paved road, and the kerb
stones are flush with the footpath.
Consideration must also be given to prevention of vehicle users (specially two
wheelers) onto the footpath wherever such a possibility exists.
3. Access ramp or Dropped Kerbs
Footpaths need to be frequently broken for cross-roads, car parking ramps and other
reasons. Usually it is observed that in such a case, the footpath is stopped abruptly.
This makes it inconvenient for pedestrians and becomes impossible for the
wheelchair bound to get on to the footpath. Hence a gradual gradient must be given,
which should not exceed 1:9.6 Care should be taken to make it non-slip.
Where relevant, provision should be made to prevent access to the footpath by
vehicle users (especially two wheelers), without compromising pedestrian or
wheelchair access. No standard design exists for this and such a design needs to be
With no dropped kerb, even with a wide beautiful footpath on the left, people will
tend to skip and walk on the road. Figure on the right shows idea of dropped kerb,
such that is is usable even by the wheelchair bound.
4. Identity maintained
Whenever the footpath is broken for certain distance, because of cross-roads,
intersections, car parking ramps and others, the identity of the footpath should be
maintained. This means, as far as the pedestrians are concerned, the footpath would
continue in a similar form on the paved road. Thus, that part of the road is of the
similar texture of the footpath. This would make it easier for pedestrians as they
clearly know what area to walk on, and for the vehicle drivers would to be extra
cautious as they drive on that area.
Figure on the left shows how the footpath gives up its identity for an off lane. On the
right one can see how the identity of the footpath is maintained, infact enhanced even
The IRC guideline2 here stipulates that the crossfall should be within the range of
2.5% to 3%. If it is too flat, it is difficult to drain, whereas if it is too steep, it would
get dangerous to walk on.
6, Surface quality
They should have an even, firm, well-drained surface which is non-slip in both wet
and dry weather. Joints should be closed and flush to prevent small wheels, walking
sticks and canes from becoming trapped.
Figure on the right shows the more desirable footpath surface – even, firm, non-slip,
no gaps big enough to cause walking sticks etc being trapped.
Covers and gratings in particular should be flush with the surface, nonslip, and have
no openings greater than 13mm wide6. It is preferable to avoid the use of gratings or
'slot' type drainage within pedestrian areas and at pedestrian crossing points because
they can trap small wheels and canes. However, if this is not possible, then gully
covers and drainage slots should be positioned as far as possible from and at right
angles to the main pedestrian flow lines.
The surface color should contrast with that of the surroundings, and especially that
of the road used for vehicular traffic.
For pedestrians and especially for wheelchair bound, sudden or irregular gradient
changes should be avoided, with gradients kept to 1:20 or less where possible.
Wherever this is not possible, a maximum gradient should never exceed 1:12.6
8. Markings to aid blind people
While this is highly desirable, good quality footpath which maintain 1 to 7 above
should be first achieved. Then one needs to begin working on making these
No IRC guidelines on this aspect are available. However, there are a number of
other national standards5,6 which have detailed guidelines for these.
9. Verge and barrier
Verges or nature strips, in addition to beautifying the road, are useful to
accommodate electric poles, lighting columns. In addition, they ensure proper
vehicle placement and development of full carriageway capacity (IRC2). They also
improve segregation between footpath and the paved road. Wherever space is
available, verges with minimum of 1m width should be given.
Wherever appropriate, pedestrian guard-rails can be given (IRC1). One must be
aware that it would not be beneficial to provide parallel parking where guard rails
are present as one would need to park at a distance to be able to open the vehicle
door. Hence, angular parking must be provided wherever parking is provided next
to a guard rail.
Guard –rail helps the control and regulation of pedestrian traffic. However, if
quality footpaths are not provided, pedestrians are likely to use the paved road and
will be further dissuaded from using the footpath even in quality streches.
Guard-rail designs are given in IRC3
Barriers can add to the safety element for pedestrians..
5.1.3 Street intersections, turns and pedestrian crossings
There are a number of different types of intersections which occur in practice.
Examples are the cross streets, pedestrian crossings, traffic rotaries, staggered
intersections etc. However, there are some common considerations which would apply
to all intersections discussed. We will go through these considerations first (section a).
We would then discuss the different types of intersections, and if there are any
additional requirements for these, they will be discussed alongside.
The design should be based on what the vehicle driver/pedestrians are most likely to do,
rather than what we want them to do.
Design considerations can be categorized as from a vehicle perspective or a pedestrian
cyclist perspective, though some are common. We will first look at the considerations
from a vehicle, followed by pedestrian and then cyclist.
Design considerations for vehicles
1. Turning radii
The path of the turning vehicle needs careful observation, to ensure there is sufficient
space for the vehicle to turn and that there is no conflict between the turning vehicle
and the vehicles in other lanes. Similarly, the path of vehicles and those of pedestrians
needs to be carefully thought through to ensure smooth flow of both and maximum
The figure shows the step by step path of a vehicle turning left at an angle of 90 deg. As
can be seen, additional space is required as compared to lanes intersecting at 90 deg.
For the sake of this discussion, we will look at the space required to the left for a left
turning vehicle, so that it does not encroach onto any other lane than the space to the
left of the leftmost lane. For urban intersections, assumptions are that the speed of the
turning vehicles are slow and the calculations are based on the vehicle almost stopping
before turning. In general, if there is a space available for an additional lane on the left,
it should be sufficient for the turning vehicles.
Figure showing the extra area required for a turn. These numbers are derived from
the standards but are for reference only, ie to give a feel. For actual design, you
must refer to IRC8
Similar is the case for the U-turn. Usually the vehicle manufacturer will give the
minimum turning radius, which will correspond to ½ of x in the figure. Appendix 1 gives
some turning radii for vehicles. For eg: Volvo bus has a minimum turning radius of
11.5m which corresponds to x=23m in the fig. Thus these are minimal numbers with
Assume you are approaching an intersection, ie a cross road at a particular speed. You
see another vehicle also approaching the intersection on the cross-road. If the
intersection is non-signalled, you need to have a view of the approaching vehicle
sufficiently before, so that you can respond and slow-down/stop by the time you reach
This is a function of the speed of your vehicle as well as of the speed of the other
vehicle, ie the vehicle on the cross-road. Given there is a human response time and a
vehicle response time, there would be a safe stopping distance which would be a
function of speed. The sight triangle visibility would be a direct function of this safe
stopping distance. IRC8 gives two kinds of non-signalled intersections,
i) “Uncontrolled intersections” where the intersecting roads are of more or less equal
importance and there is no established priority. Here the safe stopping distance is a
function of the design speed of each of the roads and the sight triangle is based on this.
Please refer to figure and table alongside.
ii)“Priority intersections” like minor road intersections where one road takes virtual
precedence over the other. Traffic on minor road may be controlled by Stop or Give way
signs/road markings. For these intersections, IRC8 recommends a minimum visibility of
15m along minor road and a sight distance equal to 8 seconds travel long major road.
Please refer to figure and table alongside.
Figure showing the visibility requirements for an intersection. In the triangle formed by
the intersecting roads and the line of sight, there should be no obstruction between 0.6m
to 1.8m. These numbers are derived from the standards but are for reference only, ie to
give a feel. For actual design, you must refer to IRC8
In addition to the above, IRC recommends that there be a subjective view of the overall
visibility of the intersection layout. This can be done by a simple view of holding the
junction drawing horizontally at eye level and observe the proposed layout from the
direction of each approach, or by drawing in a 3D tool and observing from eye level at
3. Conflict avoidance
A number of approaches to better traffic movement at junctions have been clubbed under
this section. At an intersection, there are vehicles and people coming in from different
directions and attempting to go to different directions. This gives potential conflict
points, ie points were vehicles cross each others path as well as where vehicles cross the
path of pedestrians. The techniques elaborated herewith would help minimize and better
manage such conflict points. As such, these techniques deal with the space (physical
aspect). Conflict avoidance, especially in intersections with heavy traffic, also needs
time separation, which is by putting in signaling. This is dealt in section 6.
a. Channelizing islands
Figure shows channelizing
islands(1,2) which avoid conflict,
make the traffic flow orderly
Channelizing island helps
segregate left turning traffic as
well as doubles up as a pedestrian
Combination of channelizing
islands and narrow lanes for
Examples of channelizing islands also serving as pedestrian refuge’s.
A number of pictures of channelizing islands have been shown. The above are to give a
feel and are not the only shapes recommend. Section 4.11 of IRC8 gives the standards
for channelizing islands.
These are islands formed either by marking, kerb of a physical structure used to guide
the flow of traffic as also assist pedestrians in road crossings. Things to keep in mind
while designing a Channelizing island –
- Area must be sufficient to be visible. IRC8 recommends at least 4.5 sq.m. In case of
triangular islands, the recommended length of a side is 4.5m, 3.5m minimum.
- Offset from the swept path of the vehicle by 0.6m. The approach should be clearly
marked where necessary.
- Should be clearly visible. Should be bordered with painted raised Kerbs, reflectors
for night visibility, and where necessary, a painted sign or ballard placed suitably on
- Suitable carriageway marking to guide actual vehicle
Channelizing island for U-turn
Note the use of painted areas to encourage
allowed movements, while at the same time
providing space for vehicle swept path.
b. Auxillary lanes
Auxiliary lanes exist only for short distances. They perform functions such as storage
for turning vehicles, acceleration or declaration from the main carriageway. In the
urban areas, except for expressways, acceleration or deceleration lanes are generally not
provided, except for short distances. Here the function is more for merging and
diverging and can be assisted by channelizing islands. The primary careabout here is to
ensure good visibility between merging lanes, sufficient curve radius, and sufficient
distance to accelerate/decelerate.
Auxillary lanes, specifically
acceleration/deceleration lanes used for short
distance for merging and diverging
Storage lanes or turning lanes are important in urban areas where volume of right
turning traffic is more and if not catered too, blocks the through traffic. Additionally,
because it segregates traffic, it reduces the number of conflict points and helps make the
traffic flow more orderly. It is recommended that all arterial roads and most collector
streets have turning lanes for turns. Careabouts while designing a storage lane are8
- storage lane length must be based on 1.5 times the average number of vehicles that
would store at peak hour, at a minimum
- for purpose of calculation, take length of each car as 7.5m and truck/bus as 11m
- length of area for taper (ie creation of the extra lane) should be in the range of 30 to
45m. This should be a smooth curve.8
Picture shows different examples of implementation of the concept of storage lanes for
4. Traffic calming
The slowing of aggressive drivers, ie fast vehicles for the safety of all road users may be
understood as traffic calming. This may be required at intersections, turns, pedestrian
crossings, residential neighborhood and so on. Unfortunately, in India, this has not gone
beyond the use of speed breakers. Speed-breakers are not the only method of traffic
calming. There are many others, and this section will give some examples. The idea is to
open up the road designer to the different possibilities, so that he uses the appropriate
method or combination of methods while designing the road.
The ad-hoc use of speed-breakers is one of the major reasons for traffic fatalities in the
country. See attached picture for some newspaper snap-shots which are only indicative
of the surface of the problem. Not only should speed-breakers judiciously be used, they
should be part of a comprehensive road design. The other methods of traffic calming
detailed below, as well as proper segregation of pedestrians/cyclists/vehicles, reduction
of conflict points and other such commonly used road design techniques will help reduce
the number of accidents. We have paid a very high price for not having focused on good
quality road designs.
a. Speed breakers
As mentioned above, speed breakers (or road humps as they are also called) need to
be very carefully and judiciously used. Though IRC10 has given a generic design, it
states that only one design of speed breaker may not be appropriate in all cases, and
each one has to be looked into separately. However, it would be appropriate for the
Municipal bodies to standardize on a few designs. When designing a speed breaker,
following should be taken into consideration
An IRC recommended speed
breaker design. However, IRC does
not limit it to only this. Source:
Delhi Traffic Website
- What is the speed it is designed for ? Ideally the ride should be comfortable upto
design speed and increasingly uncomfortable at higher speed
- What are the vehicles it is designed for ? Important that there should not be any
vehicle damage. A speed breaker designed for two wheelers may be ineffective for
trucks and a speed breaker designed for trucks may be dangerous for two-wheelers.
- Safety. Even at high speeds, it should not cause a person too loose control. A lot of
lives have been lost because of speed breakers
- Maintenance. Over time the
marking/paints will fade away. In
which case there is a strong likelihood
of some speed breakers not being
repainted in time, causing accidents. A
good design is one which need
- Additional signage, which will warn the drivers of the speed-breaker. Again, one
must take into account that the positioning of the signage may be improper or there
may be too much clutter hiding the signage. Though signage is mandatory, design
should not depend on the signage for safety.
From left to right. A speed hump, cushion (split speed humps) and a table (whole
intersection area is elevated). Different implementations have differing advantages. A
cushion theoretically can be avoided by a vehicle which is strictly aligned, thus
necessitating slowing without the shock. A table can also be effective without much jerk
to the vehicle but can be tougher to implement.
Before laying a speed breaker, the pros and cons should be clearly thought about. Here
are reasons one should not lay a speed breaker
- There have been a number of serious accident and fatalities due to speed-breakers.
- They can be painful to many people, especially people with medical conditions.
Conditions of people with back problem can worsen.
- They frequently cause damage to vehicles
- They increase atmospheric pollution and decrease fuel efficiency. The slowing down
and speeding of thousands of vehicles everyday adds up to cause major reductions in
efficiency and thus increase in emissions. From an environment point of view, the best
drive is the one at constant speed, whatever that is.
- Create additional road maintenance headache. A badly maintained speed-breaker can
be extremely dangerous.
Once the designs are in place, and a municipal body plans to lay a speed breaker, the
following should be thought through –
- What is the purpose of the speed breaker. In case good road design practices are
followed, there should not be a need for speed-breakers in the first place. Attempt
should be made to see if a better road design can solve the problems being
attempted to with speed breakers. (For eg: if it is a school area, giving wide
footpath with barriers, signaled pedestrian crossings with refugee islands may be
better than actually arbitrarily putting in a speed breaker)
- Can other methods of traffic calming be used
- What are the vehicles that will use this road and what speed do we need to restrict it
- Based on the above, which design of speed breaker will be most appropriate
Different types of speed breakers. Rumble strip on the left, an inverted U shaped in the
centre and the flat top speed breaker on the right.
b. Lane narrowing
(Restriping, Neck down or chokers, Raised median islands)
There are many other methods of slowing down traffic, and one which can be used
effectively is lane narrowing. In terms of effectiveness, speed-breakers are most
effective; you just have to slow down. However, lane narrowing can be made to be
fairly effective, without having the disadvantages of the former.
Here, the different methods are classified as striping, neck-down or chokers and median
islands. We will see each of these briefly.
Restriping: The soft method of narrowing lanes. Least inconvenience to vehicles,
however its effectiveness depends on compliance and that needs to be taken into
account in the Indian context.
Shoulder markings used to narrow travel
Painted center island and edgeline used to
Neck-down or chokers: This involves physically narrowing the road, by putting in
obstructions at the sides.
Figure shows lane narrowing achieved with
In addition to humps, lane is narrowed. This
results in necessary slowing down, without the
need for large humps which would otherwise be
a safety hazard.9
Figure shows how parking/landscaping to
narrow lanes can result in traffic calming.9
Median islands: These are along the centre of the road, and can be of various forms, a
couple of them are shown in the pictures below.
Tubular channelizing markers used for
center island to narrow lanes
Signboard with raised platform for traffic
c. Pedestrian crossings
The intention here is not so much to use pedestrian crossing to slow down traffic, but
the placement of pedestrian crossings should taken into account the overall traffic
pattern, in addition to the pedestrian needs themselves. In addition to helping
pedestrians, it can assist improving the traffic flow as well, as shown in the picture
Figure shows a massive roundabout(below the flyover), but concept can be applied even to
smaller roundabouts or other roads. As one can see, each entry and exit has a pedestrian
crossing. This automatically acts as a traffic calming for vehicles using the roundabout. It
regulates and balances the traffic, and the traffic can move in an orderly manner without
the need for signals or explicit speed breakers.
d. Visual modifications
This is a soft method again, but can be effective. Gates or arches can give a feel that
one is entering a residential area, a school campus or hospital. In fact these do exist,
even if inadvertently and do make an impact on traffic calming.
Figure shows how structures/
landscaping can give a clue of entry
into a residential area, there
resulting in more care by drivers. 9
e. Turns and twists, incomplete roads
Speed can be picked up only on longer stretches of straight roads. A road which has a
lot of turns or is wavy will automatically not allow fast traffic. For example, in
residential layouts, long stretches of roads need to be avoided. The constant angles
which come about will result in slower traffic, as well as heavy traffic avoiding those
lanes. The above approaches need to be done during the planning stages itself and it is
not possible to retrofit existing roads with these.
Left: In a pedestrian heavy area, route has
been made narrow and torturous (number of
twists and turns) for the purpose of traffic
Bottom: Top level view of inside of a
residential layout in Bangalore. Straight roads
end soon, number of T and staggered
intersections and wavy roads all will result in
slow and safe traffic within the layout.
The purpose of this section is not to give the standard signs or details of what signage to
use. These are already covered under IRC111 . It is rather to focus on when signage is
required, what are required to be in the standards and where should they be placed.
a. Need and what is required to be conveyed
A sign is required when a sign is required. Absence of signage when critically needed
such as one-ways, no right turn etc would end up in disaster. At the same time, care
should be taken that signage is not redundant and unnecessary. “Follow traffic signs” is
a classic example of unnecessary signage.
Figure on the left shows how a missing sign makes it potentially dangerous whereas the
figure on the right shows a unnecessary sign.
b. Clarity of meaning
Figure on the left shows marking
whose purpose is not clear.
In an ideal scenario, a sign should be self explanatory without having to resort to
language. Especially important in India, given the wide variety of languages spoken
and written and the mix of people in every city.
Figures above show the lack of standardization in signage. Standardization is a must to
It goes without saying that signage needs to be standardized. In addition to the points
that are mentioned elsewhere in this section, the following needs to be taken into
account while standardizing signs.
While creating standard signs, following should be specified
i) Size and shape (should be clearly visible)
ii) Colour coding
iii) Placement (Location, Height of signage, distance with respect to what is being
iv) Safety and ergonomics
Signage with sharp corners
protruding at shoulder height.
Can potentially hurt cyclists
d. No clutter
A very critical and often overlooked aspect of signage. When there is an excess of
signage, they do not command respect. Hence, in addition to being judicious with road
signs, it is important to minimize or reduce signage used by neighborhood shop owners,
advertisement banners etc on the road. These need to be regulated, preferably they need
to be clubbed together and placed in strategic locations, so that their needs are also
satisfied without compromising on traffic safety.
As an example, it is better to removing the no parking sign and instead use colour
coded road side kerbs or alternatively painted stripes on the side of the road. The range
is clear, does not clutter the driver visibility and is of interest only to those what want to
11+ signs in a few meters. Signage should be sparingly used, and where used, it should be
ensured that there is a minimum of other signs. Clutter as in above would result in no sign
5.2 Static uses
2 wheeler parking
4 wheeler private parking
3 wheeler[rickshaw],Taxi and Para-transit parking
5.2.3 Bus-stops and transit facilities
• Conveniently located for pedestrians
Unobstructed access to and from stop
Preferably close to pedestrian crossing
Should keep in mind that Q can build up beyond the stop itself and certain area
should be kept free for passengers beyond the stop
• Minimizes disturbance to regular flow of traffic.
Should not be so close to main junction so as to affect road safety or junction
Should not be at the entry/exit ramp of a flyover as that creates unnecessary pile up
Bus stops at the exit of the flyover can cause traffic on the flyover to back up as well
as is dangerous for those on the side road seeking to enter the main road.
• Clear of parking and other street furniture
Dissuade other vehicles from parking near bus-stop area
Should not have street furniture which would obstruct buses or bus-passengers
accessing the bus-stop
Driver should get clear view of passenger
Passengers should get clear view of approaching bus and its number/destination
• Access to other bus-stops
Should be situated to minimize walking distance between interchange stops
Tail to tail, on opposite sides of the road, preferably with a pedestrian crossing
For some reason, passengers on one side have to wait in the rain. Diagramatic
representation shows where location of pedestrian crossing and new bus stop should
Distance between bus-stops. Depending on locality, the distance should not be
excessive (> 2 km) as this would burden passengers. Inside the city, where there is
high population density, bus-stops should preferably be within 0.8 km. Similarly
bus-stops should not be too close (< 0.4 km) as this would slow down the bus
Wherever bus to different routes/destinations converge, it is better to bifurcate the
bus-stop so that there is convenient boarding and alighting.
• Bus-numbers, bus-routes and bus timings
Critical, but not done. Bus-stops should clearly have the bus numbers that stop at
their stop, their routes and destinations and timing information.
Bus-stop has most of the information, except bus timing. The bus
stop name is hardly visible and the routing information needs to be
made more easily readable and understandable.
Name of bus-stop. Should be visible from the bus as well as from a distance for
A city map which indicates all the bus routes and rational behind the bus numbering
Above should be standardized, so that each bus-stop looks and feels identical. This
will help quickly finding the relevant information for passengers.
3. Shelter design
• Seating arrangement
Are there adequate seating/standing berths depending on loading at that stop
Is the seating arrangement easy to clean and maintain, given its heavy use
It should facilitate the Q system. If there are multiple buses accessing a stop, it
should be possible for passengers to access it without disturbing the Q system
Incoming bus and number visible from where seated
Protection from the elements, ie sun and rain
• Box design aspects
Should not obstruct pedestrian footpath
Design should be such or placed such that the footpath is not
obstructed/reduced or minimally altered
Bus-stop on the left occupies the complete width of the footpath, forcing pedestrians
onto the road (red circles). For narrow footpaths, bus-stop on the right maybe more
appropriate, as it leaves ample space for pedestrians. Also notice litter bin (green).
Entry/Exit should be facilitated
Passengers entering the bus and those alighting from the bus should not
conflict, with smooth movement of both
Prevent spillover to road
We observe that passengers tend to spill over to the road and wait on the
road. This results in the bus stopping away from the stop, further
inconveniencing passengers in the stop. In addition, this takes a higher
portion of the road, also makes it unsafe for the passengers. Design
should take this aspect into account, and see if a barrier for spilling over
into the road can be incorporated.
Height of kerb
While getting into the bus, if the kerb is at a height, this will facilitate
entry to the bus. Also it will give a distinct flavour to the bus-stop.
However, it will be effective only if the bus stops sufficiently close to
Different ways of entry and exit from a bus. All need to be taken into account while
deciding the critical dimensions as shown in the figure on bottom right.
Well-lit bus stops are important for security purposes and identifying
Bus-stop signage and flag Identifying bus-stop from a distance.
Enable bus to stop close (< 6”)
Markings on the road to help driver identify and stop close to the bus-
Bus-stop and surroundings should be kept clean. A litter-bin to be
placed if required.
Clear marking (as in the right image) guides the bus driver
and passengers for the bus to stop close to the stop.
4. Driver training
All the above would not have the necessary impact if it is not supported by
extensive driver training. Among the points the training should cover is
Importance of stopping at bus-stops
Ensure that drivers stop only at bus-stops and not at junctions or mid-road to pick
How to approach bus-stops
Important that the bus approaches the stop slowly and stops very close to the bus-
stop such that the door aligns with the passenger entry.
No overtaking at bus stops. If a bus is already present, the incoming bus should wait
Minimize time spent at bus-stop
Quick but safe entry and exit of passengers. The time saved at a bus-stop means less
pile up of people and traffic, faster average speeds of the bus, thus lower travel
times for passengers. If it could be calculated, there would be a significant
economic value to lowering stoppage times.
5.3 Environmental functions
5.3.2 Garbage bins
5.3.3 Rain water run off
5.4 Utility uses
5.4.4 Telephone cables
5.4.5 Internet cables
5.4.6 Cable TV
6. Design example
Here we run through a real life example of a stretch of a road. We will look at the current state
of this stretch of road, go through its uses as listed in section 4, and see the requirements of
each of its uses as mentioned in section 5. Based on this, we will list out possible designs and
explain how it will improve the road with respect to the objectives enumerated in section 2.
…………. to be completed
7. Classification of Roads
As we explained in section 3, it is impractical to go through the design process for every road.
In addition, it is desired that there is a basic degree of standardization across all the roads in a
city. To this end, we need to build design templates which can be then used at the construction
of any new road that is being built. Given the variety of roads, there is a need to classify them
depending on use and widths.
The IRC2,7 classifies the roads as under:
1. Expressway: Function of expressways is to cater for movement of heavy volumes of motor
traffic at high speeds. They are generally signal free by providing with grade separation at
intersections. Parking, loading and unloading of goods and pedestrian traffic are not
permitted on these roads.
2. Arterial: A general term denoting a street primarily for through traffic, usually on a
3. Sub-arterial: A general term denoting a street primarily for through traffic usually on a
continuous route but offering somewhat lower level of traffic mobility than the arterial
4. Collector street: A street for collecting and distributing traffic from and to local streets and
also for providing access to arterial streets
5. Local street: A street primarily for access to residence, business or other abutting property.
The above is a good primary classification. In addition, the following should be used for
1. Width: Since the design and traffic capacity of a road depends on the width, this should be
a necessary parameter while classifying the road.
2. Zone of use: That is, is this primarily in a residential, commercial or office area. Since
usage patterns, parking, pedestrian requirements vary significantly between the above, this
is also a necessary parameter while classifying a road
3. Special uses: For example, is this road supposed to support BRTS. Or does this support a
cycle track. Again, since for these types, the design template will need to be specially done,
they need to be included in the classification.
So, as an example, one type of road based on this classification could be
Collector street, commercial, 24m width.
This needs to be worked out so that almost all (at least 90%) of the roads in the city can be
covered in this classification
A similar approach and template designs are covered in IRC7. However, these reference
designs are not comprehensive, and are primarily done only to give the desired width
…………. to be completed
8. Design templates for each road type
Based on the above classification, a number of road types were obtained in section 7. As
mentioned in section 3, every class of road needs a template. Here we show example of one
template – the utilities section has not been shown.
8.1 Template for 30m wide, sub-arterial road, mixed (commercial + office) with single cycle
Section view (bottom), plan (top right) and 3D view of the basic scheme of the road.
The shoulder area can be occasionally used for car parking, hawkers, trees, greenery
etc. Median area can be used as refuge islands for pedestrians and cyclists.
Left turns, Right turns and intersections. Storage lanes
are created for turning which results in good throughput
Bus=stops plan view and street view. Bus-shelter does not interfere with
pedestrian area as well the bus stopping area is segregated from the
normal lane traffic. Pedestrian crossing with refuge area between the
opposite side bus shelters
…………. to be completed
1. Guidelines on regulation and control of mixed traffic in urban areas. IRC:70-1977
2. Geometric design standards for urban roads in plains. IRC:86-1983
[This document for cross-fall contradicts itself between section 6.2.5 (2.5% to 3%) and
section 8.4 (3 to 4%). Ref 4 goes by max of 2.5% and we will go with the former
3. Guidelines for pedestrian facilities IRC:103-1988
4. Accessible bus-stop design guidance
Bus Priority technical team advice note BP1/06, January 2006
Transport of London
5. Manual for streets
Department of transport
Thomas Telford publishing
6. Accesscode: a Code of Practice on Access and Mobility
An advisory code reflecting current statutory requirement and best practice within the
7. Space standards for roads in urban areas: IRC:69-1977
8. Guidelines for the design of at-grade intersections in rural and urban areas. IRC:
Special publication 41-1994
9. Geometric design practices for European Roads – Context sensitive solutions.
Study of European roads and road design practices by a US study group
10. Tentative guidelines on the provision of speed breakers for control of vehicular speeds
on minor roads. IRC: 99-1988
11. Code of Practice for Road Signs. IRC: 67-1977
…………. to be completed
Appendix 1:Interesting links
A report on remaking new york streets. Tastefully done.
Excellent video on the New York street redesign – a must watch.
The above site, ie streetfilms.org has a lot of excellent videos one can go through.
Study of European roads and road design practices by a US study group
Council meeting in Albuquerque on speed-humps, interesting discussion, more so for the way it
is carried out.