I READ with interest (The Press, January 11) of the cross-party support for ‘improvements’ to the A1237. But a note of caution is needed. Ever since 1925, transport professionals have been aware of what is known as “induced traffic”.

This rule suggests that any predicted cuts in congestion claimed for a new or widened road are quickly eroded by additional journeys.

Traffic levels on bypassed roads can also rise faster than expected due to induced traffic. Recent reviews have confirmed that induced traffic is still beating forecasts, on new and widened roads across the UK.

If long-term traffic levels are not properly forecast, the benefits and costs of a new road will not be accurately calculated. This can lead to big mistakes being made with public money.

Widening the A1237 could also create substantial physicals barrier for pedestrian and cycle movements from commuter settlements located to the north and west of the city.

Before the dash to ‘upgrade’ this road begins, appropriate advice must be sought from the transport planners. A past report by the council’s consultants, Halcrow, found that the roundabouts were the true pinch points, and that the single carriageway roads between could accommodate forecast demand up to at least 2021.

Paul Hepworth, Windmill Rise, York.