New roads mean more traffic: Dr Tony Whitbread – chief executive, Sussex Wildlife Trust

And, of course, if there was another road then all the other cars would use it, relieving congestion everywhere.

A big, new road is something simple and obvious. You can put a ribbon across it and declare it open, to a fanfare of appreciation from an appreciative economic sector who are now happy (until the next time).

The Department for Transport is developing its A27 feasibility study and also seems to be swallowing all these old assumptions. But life, however, is not that simple. Simple solutions to complex problems are always wrong.

As in the past, environmental concerns are pushed to one side. One option for the Arundel bypass will cause the greatest loss of ancient woodland in Sussex for the last 20 years, the other will destroy the setting of two villages. But to some this is a price worth paying in order to relieve congestion and stimulate the economy.

So we get back to the “your money or your life” approach of balancing the economy against the environment. But whilst the environmental costs are measurable, severe and obvious, the economic benefits are shrouded in mystery, assumption and pre-conception.

Economic benefit is based on reduced travel times and perception surveys about how much better business would be if congestion was removed. Ask a business how much better life would be and you get an obvious answer. So arguments build up to support a road-building case. Businesses, however, need real solutions and views very quickly change when the reality of a situation becomes clear.

Road building does not deliver the relief of congestion that is generally claimed – quite the reverse. Roads generate new traffic and that creates new, and worse, congestion. This is not the view of an “anti-road green group” but the clear conclusion of study after study.

The Standing Advisory Committee on Trunk Road Assessment in 1994 found that an average road improvement, for which traffic growth due to other factors has been forecast correctly, will see an extra 10% of base traffic in the short term and 20% in the long term.

The assessment looked at roads surrounding trunk road improvements – their use went up on average by 16%. So roads that are supposed to be relieved by a new road receive 16% more traffic than the predicted increase.

Even in the unlikely event that the A27 flows more freely following enlargement, surrounding roads in towns, countryside and villages will receive more traffic, more congestion, more hold-ups and more pollution.

What is more, this sort of conclusion, with these sorts of figures, has been reached again and again, on average every eight years since.

About every 10 years we go through the same process. First we insist on forgetting the lessons of the past and push for new roads. Roads get built, the environment suffers more damage, traffic gets worse and congestion increases. This results in demands for yet more roads and more environmental damage until, eventually we have to realise the reality of the situation and seek more sophisticated solutions.

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