A fresh headache has emerged for planners drawing up regional spatial strategies. Latest population projections show that over the next 25 years people will continue to leave some of England's major towns and cities.
All bar one of the nine English regions show signs of a population increase between now and 2028, with the East of England seeing the biggest rise at just under 17 per cent. The North East is likely to see a two per cent decrease, reducing its population to 2.5 million. Redcar and Cleveland and Middlesbrough are expected to see falls of up to ten per cent.
But the outcomes are not clear cut. Even in regions where the population is set to rise, some places will see a decline, especially in market renewal pathfinder areas. Merseyside is projected to lose nearly 20,000 people over the next 20 years. Over the same timescale Hull will lose 27,000, Newcastle more than 10,000 and Stoke-on-Trent almost 18,000.
Most areas will see a decrease in their younger population, while in London and the East of England the number of elderly residents will climb faster than the number of young people.
The Office for National Statistics, which issued the figures, stresses that they are projections rather than predictions. "The sub-national population projections use historic demographic data to make assumptions on future demographic behaviour," it explains. "They do not take into account future housing or other policies for specific areas."
That has not stopped the environmental lobby asking how the shifting population will affect housing and regeneration policy. With England's population expected to rise to 54.4 million, the Campaign to Protect Rural England (CPRE) points out that the declining number of people in certain towns and cities poses a challenge for urban renewal.
"We believe passionately in urban regeneration, not least because it can help reduce development pressures on the countryside," says chief executive Shaun Spiers. "So while we welcome the progress made with urban regeneration in recent years, there is still a long way to go."
Spiers has called on the government to introduce stronger policy measures to even out economic growth and prosperity across the country, reducing development pressures on the South East. Building more affordable housing at higher densities will also help to protect rural England, a recent CPRE document argued.
Martin Willey, chairman of the RTPI regeneration network steering group, says: "A number of initiatives over the past 20 years have resulted in individuals gaining more skills and the first thing they have done is escape the area. To put it simply, if the jobs are not located locally, people will go to the jobs."
But a broad range of infrastructure problems will exacerbate an area's decline, Willey contends. For example, a region with adequate road and rail connections but problems with telecommunications, making it harder for people to apply for work online, can lead to population shifts. The solution, he maintains, is investment in skills, local opportunities and regional economies.
It is not all bad news. If the projections prove accurate, the situation that emerges on the ground could provide further opportunities for regeneration.
If no-one is living in an area there will be less local opposition and nimbyism. "It may present an opportunity for more wholesale demolition to create a more attractive living environment," Willey argues.
Yet the fact that the population has been shifting for decades, with few signs of change in the underlying trends, is evidence that government-backed regeneration initiatives such as the sustainable communities plan and The Northern Way must constitute much more than housing and job creation schemes.