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Debate Road capacity

The rail industry is in crisis, the cost of motoring falling, the number of cars growing and the government's ability to deliver sustainable transport solutions in doubt.

This week we ask: Is extra road capacity the best way to solve Britain's transport congestion problems?


Tim Matthews, chief executive, the Highways Agency.

Over 90% of travel is along roads.

Congestion is a major cause of disruption, uncertainty and cost to individuals and companies.

Tackling road congestion is, therefore, one of the key elements of the government's transport strategy and is at the heart of the Highways Agency's mission to provide road users with journeys that are safe and reliable.

Easing congestion, particularly against a trend of growing traffic volumes, requires a balanced strategy, and one that tackles the causes of congestion.

Increasing road capacity is an integral component of that strategy. The 10 year plan provides for widening of 575km of the motorway network and the multi-modal studies are now coming forward with recommendations on where and how this might be achieved.

But increasing capacity is not just about laying more blacktop.

Capacity is also constrained by bottlenecks in our network, whether they be inefficient junction layouts, roads running through small congested settlements or road layouts and alignments that inhibit free flow of traffic. The Agency's programme of junction improvements, bypasses and smaller targeted congestion schemes are all designed to improve capacity at these critical nodes.

We can also improve the capacity of the network by managing it more actively. Pilot schemes such as variable speed limits, ramp metering and climbing lanes are already showing benefits in smoother and safer traffic flows.

Maximising lane availability is the other area where we can significantly increase capacity.

Over a third of congestion arises from either incidents on the network or as a result of roadworks.

The Agency has already made significant progress with its contractors in minimising the impact of roadworks on users and in restoring the roads to use after accidents.

It is all too easy to caricature increasing capacity as a fireturn to predict and provide'. That is not the case. Equally it would be dishonest to pretend that congestion can be reduced without some increases in capacity. The key issue is to strike the right balance between the new provision that is essential, the targeted schemes which alleviate the bottlenecks, and the better management of our road space.

Not predict and provide - but intelligent assessment and rapid delivery.


Phil Goodwin, professor of transport infrastructure, University College London.

Building extra road capacity - what an extraordinary proposition. What a strange sense of déjÓ vu one gets at this relic from a long-lost time of innocence, when 'predict and provide' was believed to be a strategy that would actually work. And how sad that people are still willing to back such an aim.

The proposition is wrong, not only because of the environment, the social and equity implications, the sheer unlikelihood of getting public or sustained political support, or because of the drain on limited finances it would entail but mainly because it simply will not work. That is a technical issue, not a moral or political one.

In current conditions, traffic volumes have the ability to grow faster than any feasible road building programme, which means that in conditions of congestion especially, induced traffic must undermine a large part of any benefit of extra capacity, and may overwhelm all of it.

The resulting benefit, so much less than hoped for, will rarely be good value for money, and almost never be best value for money.

When the supply of road space simply can not keep up with traffic growth, the main and most important instrument of reducing congestion must be demand reduction - whether by price, rationing, physical restriction, priority, or reallocation of road space to protect the most important or most needy classes of traffic.

There will be, of course, some reduced remaining role for road building. But the justified schemes will be quite different in size - and even in location - from schemes designed on the assumption of unimpeded traffic growth.

And the proof? All the road schemes in the government's 10 year plan, even if delivered fully, successfully and on time, will result in a reduction in travel time over the whole network of about one second per mile travelled, and it will take a decade to get it.

On the motorways and trunk roads for which the Highways Agency is responsible, the difference will be less than half a second per mile. That is what the Department of Transport, Local Government and the Regions' own calculations show.

Solving congestion? Not.

The facts

Tim Matthews and Phil Goodwin will be teaming up with British Consultants & Contractors Bureau and Transport 2000 director Stephen Joseph to debate the issue live at Civils 2002, 2pm, 12 June, at the NEC, Birmingham.

To pre-register visit www. lUnder the government's 10 year plan, 100 bypasses will be built and 575km of motorway widened. A revamped 10 year plan is expected to be unveiled by the government in July.

lIn 2000 the government vowed to cut traffic congestion by 6%. To achieve this government should be promoting urban and interurban road tolling, said Commission for Integrated Transport chairman David Begg. His view is has recently been backed by the RAC, business lobbyists the CBI, the Institute of Directors and the Construction Industry Council (CIC).

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