Concepts
Traffic Management in Mumbai
Dedicated bus lanes
Dedicated bus lanes have been used all over the world to provide buses priority over other motor vehicles as they carry more people per road space occupied. Dedicated bus lanes are usually marked with a solid white or yellow line along with a ‘Diamond’ or ‘Bus Lane’ written on the road. Since lane discipline is not strictly followed in Mumbai, merely marking a solid line is not enough. An alternative is to mark a solid line and fix plastic dividers or spring bollards to segregate the bus traffic from other motor vehicle traffic. A bus lane is ideal where there are no openings as left turn in driveways. A bus lane has a number of advantages:
- Provides buses priority over other motor vehicles as the speed of buses increases
- Capacity of road to carry commuters increases dramatically
- Buses and vehicles do not come in each other’s way preventing chaos
- Reduces the chances of illegal parking
A BUS LANE IN LONDON
BUS LANE AT HAJI ALI MUMBAI IMPROVED BUS THROUGHPUT BY MORE THAN 40%
Right turn management
Right turning traffic is one of the major causes of friction, which reduces the average speed of vehicles thereby reducing the throughput of straight traffic. Right turning traffic has opposing traffic due to which vehicles idle in the right lane (supposed to be the fast lane) thus affecting the movement of straight moving vehicles. There are a number of ways to manage right turns to overcome this problem. A few of them are listed below:
1. Carving dedicated right turn lane by tapering the divider
In the above image, a wide divider (~3.5 meters wide) has been tapered before the intersection to create a dedicated right turn lane. Since the straight and right signal are rarely linked together, the right turning traffic can be stored in the section that has been carved out so that it does not come in the way of the straight traffic. In Mumbai most dividers are approximately 1.5 to 2 meters wide. The right lane is usually shared by straight and right turning traffic which creates friction & confusion and increases the chances of rear end collisions. These dividers can be widened by 1 meter on each side in order to carve out a turning lane. Once the turning lane is carved out the right turning vehicles will queue behind each other on either side of the intersection and will have a different traffic stream from the straight travelling vehicles.
2. Dedicated right turning lane by drawing a virtual island
A few roads in Mumbai are very narrow and in addition, they also have narrow dividers. In cases where the road width does not permit widening of the divider, a virtual island can be drawn to create a dedicated right turning lane. As seen in the image, the vehicles travelling straight will move along the yellow line into the straight only lane while those wanting to turn right will move over the virtual island and drive into the dedicated right turning lane.
3. Blocking right turns at critical intersections and rerouting vehicles
Some intersections which have a high percentage of right turning vehicles create long queues as they block the straight moving traffic. Right turns at these critical junctions can be blocked and motorists have to take a different route. A perfect example of this is the right turn at Mount Carmel Church near Lilavati Hospital, Bandra. The right turn at this intersection blocks traffic on two arms in both directions, creating long queues. If the right turn is blocked all vehicles will travel straight and take the next right where the conflict between vehicles is less. Even though motorists wanting to turn right will have to travel longer the overall time saved is drastic as there is no stopping. A similar rerouting system has been operational at Mahim Church Southbound where vehicles are directed to proceed straight to LJ Road once the Cadell Road signal turns red. This experiment has increased vehicular throughput by more than 600 vehicles per hour.
Channelizing traffic using plastic dividers to improve lane discipline
The above picture shows an experiment that has been carried out by the traffic police on Mahim Causeway Northbound towards SV Road & Western Express Highway. A board has been put up about 250 meters before the bifurcation instructing motorists travelling to different arms to keep on a certain side of the road (example: Lane Separation Ahead - SV Road keep right, WEH keep left). Vehicles right of the plastic dividers go to SV Road while those to the left go to Western Express Highway. If the cones are not placed then the SV Road traffic blocks the Western Express Highway traffic by staying left. This experiment improved lane discipline considerably and can be tried out at many other road sections in Mumbai.
Blocking unnecessary section of a road
Many roads in Mumbai are wide at one section and then narrow down closer to the intersection. This design is in the form of a bottleneck. A bottleneck increases conflict between vehicles as a higher number of lanes merge into a lesser number of lanes (eg: 5 lanes merging into 3). Conflict between vehicles reduces the average speed of all vehicles as they have to be more watchful. This results in lesser throughput of vehicles past the junction within the allotted time span, thus increasing queues. By blocking the unnecessary portion of the road, vehicles queue in the same number of lanes that are there at discharge thus improving traffic flow. An experiment was done at the exit of Western Express Highway on Mahim Causeway where 6 lanes would usually merge into 3. After blocking 3 lanes to the right, the entry and discharge was constant which improved traffic throughput by more than 30%. This experiment proved that a wider road does not necessarily mean lesser congestion.
Cycle Lanes
Cycles are an excellent mode of transport for short distances. They do not pollute and also occupy much lesser space on the road than other motor vehicles. Dedicated cycle lanes aimed at promoting cycling for short distances have become very popular in many European & East Asian countries. If cycles are used instead of motor vehicles for short distances, the level of congestion and pollution is expected to drop drastically as observed in many cities that have promoted cycling. Cycling lanes are separated from other motor vehicular traffic using thin/low dividers or spring bollards which improve their safety and also provide priority over other modes of transport. It is also important to have cycle racks at as many locations as possible so that cyclists can park without the fear of their cycles getting stolen. Since India is a very status conscious society, it is definitely going to be very difficult to convince people to adopt cycling as a mode of conveyance for short distances. It is however, absolutely worth giving it a shot. Below is a photo of a cycle lane in a European City.
One-way Streets
One-way streets reduce conflict between vehicles as there is no opposing traffic. The right turning problem is also eliminated as traffic is moving in one direction, so the right turning traffic does not idle in the fast lane. One-way streets improve traffic flow of all vehicles and are ideal to promote bus/cycle lanes and regulated parking. Linking road/SV Road and its surrounding streets have a grid iron planning with many links connecting the major arteries. These roads are very congested throughout the day and it can take anywhere between 12 to 20 minutes to cover a distances of barely 3 kilometres. If a detailed study is carried out, then this area is ideal for a Manhattan style One-Way grid which could reduce congestion and travel time considerably. Below is a map of the Linking Road/SV Road area showing how a One-Way grid can be planned.
No Parking/Stopping Zones
Parking on major arterial roads is one of the major causes of traffic congestion. To reduce congestion, parking has to be regulated or else the scenario is not likely to improve. Parking at intersections is very common in Mumbai which reduces speed drastically thus increasing the length of queues. Currently motorists have a problem in understanding whether parking is allowed or prohibited at a particular portion of the road because of boards that read: ‘No parking 30 meters from the board’. It is not very easy to understand how far 30 meters is. To avoid this confusion, the portion where parking/stopping is prohibited can be painted in a different colour. For example: Most footpath corners are painted black and yellow. Similarly, the No Parking Zones can be painted in red or yellow with white arrows. A board explaining what the colour means can be put up to guide motorists.
Stopping before the stop line
It is generally seen that most motorists rarely stop before the stop line at an intersection and instead end up stopping on the zebra crossing. We have observed that there is a psychological reason for this. The end of the divider is the point of safety for the motorist as vehicles in the opposing streams are going to take a wider angle and not conflict with the stopped motorist. As a result of this, the motorist will stop at the end of the divider. Pedestrians too want to cross the street at the same level. They, therefore, end up crossing from the left of the zebra crossing, as if to walk on the zebra crossing they have to climb over the divider. As shown in the left part of the image below, if the divider is set back a few meters, that is, the divider and stop line make an inverted “L” and if the zebra crossing is at the same level as shown in the right side of the image below, it will be a win-win situation for both, the motorists as well as the pedestrians.
