Innovation against congestion.

Congestion is one of the major problems that traffic engineers and planners are asked to deal with. In the past the most commonly proposed and adopted solution to congestion was the design and construction of new roads. New urban motorways and arterials shaped the way that our cities look and operate but failed to address the problem at the longer term since there was a parameter that was never thought off. Raging induced traffic soon clogged the new arterials or the added lanes on the urban motorways. Now, scientists even say that adding traffic lanes can even reduce overall performance.

And while this effect is not always recognised by politicians who seemed to prefer planning and designing for cars and not for people, the new political shift to cutting down state debt and deficit, meant that there were no longer huge amount of money for big transport infrastructure projects. But still the desire to deal with congestion remains as drivers lose time, waiting in stand still conditions while they are trying to get to and back from work every day. And since commuter traffic has two peaks within each day, going towards the city centre every morning and away from it towards the suburbs each afternoon, using the empty lanes and the surplus capacity on the opposite direction was a sensible thing that a few transport agencies tried to explore.

 

Source

Greek traffic police change the direction of a lane by placing “witches hats”. This is a measure that they use on rare occasions though; usually on long weekends and big public holidays like Easter and Christmas. This mass movement is called by the Greek media “the exodus” and “the return”.  Friday afternoon, highways that connect Athens and even Thessaloniki to the rest of Greece get an extra lane on the outbound directions and this is reversed on the day that everyone returns back home at the end of the long weekend. This is quite labour intensive and that’s why it’s not considered feasible for an everyday, commuter type solution.

There is a mechanical alternative to this treatment. It’s called “zipper” or barrier transfer machine as is the correct technical term. The zipper is a customised heavy vehicle used to transfer concrete lane dividers shifting a lane to be used for the opposite direction. Back in 2001, in the I-95 highway in Richmond, USA these machines were quite large and very slow moving. 

Source: Roads to the future

In 2013 zippers got a lot smaller and a lot quicker as shown in this video from I-15 in San Diego, USA.

The concrete barriers which can weigh almost half a tonne are linked together by metal connectors and are not anchored in the ground. This requirement creates a lot of constraints and limits its application in road sections that meet such conditions. Wide medians are excluded so are concrete barriers with lighting poles between them.  

Pacific Motorway, Tanah Merah, QLD

A simpler solution is having reversible lanes without any hard separation but rather than with just variable message signs like the one shifting the middle lane in Queens Road in Melbourne.

Queens Rd, Melbourne, Victoria

Innovative, clever solutions provide value for money but in order to achieve large scale benefits, a paradigm shift is necessary. Shifting away from car traffic and towards public transport and active travel and supporting this change with not only the funding but also the ingenuity that traffic engineers and planners have proven they possess.