‘Computer says road’: call for change to ‘crude’ planning models

“Crude” computer programs that prioritise new road building should be banned from the design of new housing because they cause billions to be diverted to roads that could be used for creating more compact communities, campaigners claim.

Robert Booth www.theguardian.com 

Traffic modelling spreadsheets that “almost always tell us that ‘computer says road’” should no longer be used by planners and more money should be spent on building places geared for walking, cycling and public transport, according to a report by the Create Streets campaign.

It has been endorsed by Rory Stewart, a former Conservative leadership candidate; Toby Lloyd, a former Downing Street housing adviser and the Royal Town Planning Institute.

The attack on “big road urbanism” argues that the Department for Transport cost-benefit modelling tools for new roads fail to “properly capture non-travel-time benefits, such as health, wellbeing and the environment … so the answer will always be to build more or bigger roads”.

The Department for Transport strongly denied any bias towards road-building in its modelling, and a spokesperson said: “The environment is at the heart of our proposed transport schemes, and we always encourage sustainable options such as public transport, cycling and walking.”

The Create Streets thinktank is led by Nicholas Boys Smith, a former adviser to George Osborne, and has worked with architects and urban designers close to Prince Charles to argue for more human-scale planning.

It believes billions in taxpayers’ money could be saved by changing decision-making on road building, with smaller sums instead spent on placing shops, gyms and other social infrastructure closer to homes linked by buses, cycle paths and walkways. The result would also be healthier and greener, it argues.

As an example of what it believes is going wrong, it is highlighting plans to spend £1.4bn building one roundabout and 10 miles of new road near Bedford.

The 2km-wide Black Cat interchange covers a space bigger than York city centre, which is one of the UK’s most walkable cities. But transport planners say the project will relieve heavy congestion and save drivers an hour and a half on their journeys every week.

Traffic delays in England were at close to their highest level since 2015 just before the pandemic, but almost halved during the first lockdown. They have since been rising again towards peak levels. The government is pressing ahead with a £24bn road-building and renewal plan announced in 2020.

Several road projects were announced last year as recipients of the £1.7bn “levelling up fund”. Road building is already the single biggest annual outlay for councils, which last year allocated £7.5bn, or 29%, of their total capital expenditure to highways and transport services. They spent ​​£6.1bn on housing.

Create Streets highlights how scores of streets and squares in a popular medieval city like Siena in Tuscany can fit into the space taken by a motorway interchange in Houston, Texas.

“Instead of spending tens of millions of pounds on one junction or on widening a few miles of road, we should instead design better places where more journeys are by foot, bike or public transport,” said David Milner, Create Streets’ deputy director. “We can do this by siting amenities we want to visit in the heart of new developments, not their perimeters.”

Planners and developers have for decades used computer models to determine transport plans that tend to put the needs of rush hour traffic first. The impact of the pandemic, which has led to widespread remote working, and the pressing need to slash carbon emissions from domestic transport, which emits 27% of all of the UK’s CO2, are increasing calls for change.

“We are seeing e-bikes being a car killer,” he added. “They increase the range and the frequency of bike riding.”

The study is also being endorsed by CPRE, the countryside charity, and warns that good design principles for new and regenerated communities are being “cast aside”.

“We are told the ‘infrastructure won’t cope’ or ‘the junction can’t take it’,” said Milner. “Almost every traffic model tells us that ‘computer says road’.”

Andrew Taylor, the planning director of Countryside Properties, one of the UK’s largest housebuilders, is also backing the call for change.

“This is not about avoiding investing in necessary junctions and improvements but about trying to refocus our energies and money on placemaking, 15-minute communities and foot and cycle connectivity within developments to reduce the need for these other physical interventions,” he said

A DfT spokesperson said: “Our modelling works alongside our £5bn transport decarbonisation plan, £2bn of which is specifically invested to encourage active travel.”