Understanding congestion

A large part of road safety that often isn't well understood is traffic congestion.  Too many cars on our roads can lead to problems where disruptions in the flow of traffic lead to accidents.  With our primary roads in Bermuda being littered with driveways and entrances to side roads, traffic flow disruptions can be frequent as people being courteous by letting people in and out can cause problems for those behind them, just as when the flow of traffic wants to go one speed, and one driver cares to go another.   

If traffic congestion isn't a topic you've studied in much detail, here's a novel video that'll give you the gist of it.

Note the cars driving around in a circle smoothly and with no congestion up until the point where a small blue car hits its brakes to slow down.  This simple action causes every car behind it to also slow down, despite his attempt to quickly catch up to the car ahead right after.  This slowing effect propagates through the entire line of traffic bringing the cars at the other side of the circle to a standstill. 

This sort of scenario occurs when traffic follows each other too closely or when roads become too congested to allow large enough gaps between cars.  Such stoppages can easily be caused by many situations such as drivers going against the flow of traffic.  Examples include driving 35kph when everyone behind them expect to go 50kph or when a driver stops to let someone in or out.  Often unknowingly, a driver can cause a long backlog of congestion to build up behind them which can bring cars a ways back to a halt.  Even worse, it has the prospect of causing accidents to occur as drivers following too closely or not paying attention can careen into the rear end of the car ahead of them, or worse as they attempt to avoid the collision.  Backlogs also cause those on bikes to 'third-lane' in frustration at the abundance of single passenger cars that add to the congestion.  The larger this backlog gets, the greater the risk that any one car can cause undesirable affects. 

In many places, Bermuda is nearing it's limit for the number of cars that it can handle at any given time and yet the depth of publicly published studies produced on congestion in Bermuda is disappointingly non-existent.  What traffic analysis and modeling occurs to ensure that our roads can handle added congestion?   Could we invest in congestion tracking solutions as a means to better understand the areas that cause congestion so they can be addressed?  Would introducing legislation allowing car sharing initiatives to be created be effective in reducing the number of cars on our roads?   Would a trial of a congestion tax during busy hours be a viable way of determining whether the implementation of a congestion tax would be effective? 

Further, although the speed limit is officially 35kph, the unwritten accepted speed limit is nearer to 50kph.  When everyone is expecting to travel near 50kph and one car travels at 35kph, congestion can build up behind them like in the video above and that backlog becomes increasingly susceptible to accidents.  Although government and police officials are quick to remind us that the speed limit is 35kph, are we causing more problems than we're solving by maintaining that limit when the flow of traffic really is closer to 50kph?

What can we do to reduce congestion and make our roads safer?

Comments

[YAL]

Dennis,

I think you're wrong about the level of road safety involved in congestion.

In Bermuda most road deaths come from two sources:
1. Crashes in the late night/early morning when there is little traffic on the road.
2. Dangerous Overtaking (and use of the 'third lane'). Though this is due to bike riders getting bored sitting in congestion.

My answer to both these issues, (which no one else on the island agrees with) is to allow more cars on the road!

Car safety features have now developed to the point where people really shouldn't die at the speeds seen on Bermuda's roads. Yes, I know we did have one unfortunate death of a young mother in a car, but she wasn't wearing her seatbelt.

Sure it's going to take a while to get anywhere, but think it could save 9 lives a year! Wouldn't that be worth it?

[reefmuncher]

Hey Dennis that was a good video displaying traffic congestion!

I know from riding a scooter to work in the morning it is quite frustrating to see every 3rd car to be a single passenger vehicle, which burns 5 or more times as much fuel on each journey.

I notice riders on bikes develop a certain method to leapfrog traffic and if certain rules are followed is of low risk. Of course some riders 3rd lane which is pretty rude to oncoming drivers.