I have for some time wanted to share how planning road layouts is vital for ensuring traffic flows smoothly.

Here is the first in what I hope to make a series (and hope other contribute too) of road layouts from UK. Aim is to share these observations with our planners to reduce entropy on our roads.

A Typical cross junction in UK

Layout example 2: A typical T' Junction

Example 3: Layout of pedestrian zebra (without traffic lights) at a T-junction. The layout automatically makes the zebra more than just a pedestrian crossing, it becomes a tool for regulating traffic, allowing vehicles either joining or leaving the main road safely when traffic waits to let pedestrians cross safely - want to see a video example? My video on Zebra belongs to pedestrians [1] has an example, wait till you see the bus stopping for pedestrian at the zebra and see how it gives a chance for another vehicle to safely cross over to a side lane.

ASJ

Case example 4: A typical roundabout, again pedestrian zebra crossings without any traffic lights help regulate the traffic (along side the right of the way rules of a roundabout).

Road Layout Example 5: T Junction's and Right of the Ways

Here is example 5 showcasing how clear road markings and signage removes conflict, establishes right of way and hence reduces entropy.

More road layouts: Bus Bays, Major cross junction and U turns

Ok, these are case examples 6 to 8.

First, example 6, looks at bus bays

Example 7 - is a major crossroads or intersection on a 6 lane dual carriageway - note the similarities with example one at the top.

Example 8 - same dual carriageway but a demonstration of how a conflict free U turn facility is provided

Case example 9: Road typology

UK has a clear road typology, this helps planning and implementing layouts and safety measures for the given function of the roads in keeping with vehicle and pedestrian density.

Freeways are Freeways and City Roads are City Roads, there is no confusion about that.

By definition a Freeway is - FREE - of pedestrians / cyclists and T or cross junctions. Our planners have never either understood this or did not care or had ulterior motives.

Let me illustrate by beginning with a freeway/ motorway in UK. This is M1 going from London (South) to Northampton and beyond to Scotland.

As you can significant planning and care has been taken in the above design which replicates all over UK.

The Blue circle is Northants county with residents and industrial estate.

Now lets look at NH4 as it cuts through Pune -

As you can see the blue circle and the thick residential / commercial growth was allowed by civic officials-politician-builder nexus

Now lets look at Mumbai-Pune expressway, supposedly one of the best planned ones in India -

Now we just have to wait to mess up the Mumbai-Pune expressway - its only a matter of time as the image below shows that already planning permission is being granted to builders to develop adjacent to Highways and open their driveway's right in to the Highway - 

Now see the image of Bangalore with the NH4 -

The red line cuts through the city (once upon a time when the city was small it was a different story). Note all other highways cutting across inside the blue circle. There is no problem in developing on either side of a freeway or motorway/highway but if Pune (and so also Bangalore) had ensured that development is off-set by 30 meters, slip roads will have become part of the infrastructure.

Its too late now, but in effect NH4 within city limits has been rendered in to any other city road - full of junctions and pedestrians and we can only blame our civic staff for it.

A ring road will be useless, instead a motorway design linking inner Bangalore with every major National or State Highway (red circle below) will do the trick -

It may seem like a detour for traffic going through but actually it will be much faster.

This will also mean that highway sections within the Red Motorway will have lesser traffic , making them safer.

Further, the highway sections within the Red Motorway need to be re-classed as dual carriageways.

By re-classing them, the appropriate pedestrian safety infrastructure can be put in place.

Right now we are trying to treat highways within city limits as highways when in fact they have become city roads.

Below I am using Google Images to showcase the M25 motorway and how it connects not just with inner London but all other Motorways - this is Freeway designs at its best (when Pune and Bangalore talk of ring roads, anything other than something planned on the lines of M25 will fail).

I am not a fan of mega projects, but if there is a need for one when it comes to road building, we need something like this rather than the hotch potch of flyovers within cities that are designed to push chaos from one junction to the next and nothing more.

Additional inputs with regards junctions and layouts - 

A footpath never loses its identity - another compilation where I have demonstrated how the identity of a footpath is maintained throughout - this is needed on all our roads.

Part one gives several examples http://better.pune.googlepages.com/PreservingFootpathsIdentity.pdf, part II focuses on one new design spreading rapidly across London in recent times - I prefer this design on sections where small lanes meet major roads (not a major crossroad junction) http://better.pune.googlepages.com/Preserving_the_identity_of_a_footpat.pdf

Case example: Location of traffic lights

Correct positioning of signals / traffic lights to reduce vehicles standing beyond stop line - http://better.pune.googlepages.com/TrafficSignalsPics.pdf

Case example: A video showcasing a traffic lights sequence -

http://uk.youtube.com/watch?v=bD8yh6EJY4I

Case example: Why spend on subways and skywalks when staggered crossings could do the trick?

Again, pedestrian crossing can be facilitated at cross roads as part of overall regulation of traffic - this is exemplified below 

It’s rather simple whether at a junction (crossroads or a T) – pedestrian crossings and movement can be integrated within traffic lights cycle by use of pedestrian refuges. Let’s look at the image below -

Now let’s presume the traffic lights cycle is 20 seconds for each direction. The traffic is moving from A to B, D and F. This means pedestrians can cross half way on H, G, E and C sections. Now let us presume, that next, all cars coming along E were given a green light to go to  F, H and B. This means pedestrians on sections A, C, D and G can cross halfway. In short, during the traffic lights cycle it self pedestrians can cross over with safety, for some sections depending on what part of the cycle they arrive to cross, pedestrians may take a minute to cross over across two sections.

This is the most cost-effective means of serving both the purposes. Even with skywalks or subways, traffic lights are going to be needed to coordinate vehicular movement anyway, so why not use the pedestrian refuges (grey rectangular boxes).

Currently in Pune, the problem is that traffic lights try to make pedestrians cross across entire road lengths (sometimes 4-6 lanes within 6 seconds). This leaves pedestrians having to take risks, oft leading to chaos on our roads as vehicles try to pass them on either side. 

Staggered Crossings - another missing infrastructure / feature from the Indian roads.

Here are more examples of staggered crossings - Click to view this file

Here is a slideshow of more examples including subways in total disuse 

1. Signs are illuminated by the street light
2. By co-locating bus stops and street lighting where possible bus stops do not need additional lighting (or it is minimised).
3. Clutter of poles and street furniture is drastically reduced.
4. Cost savings by not having to spend on material as well as reduced expense on additional lighting and overall maintenance

 And finally some traffic calming measures on narrow roads for improving pedestrian and general road safety: 

A curved route to slow down vehicles on Hounslow High Street which has heavy pedestrian density- 

A speed breaker / hump no one can get away from - 

Dr Adhiraj Joglekar