Hamish McRae: We have to plan for a bigger population

So by 2051 Britain's population is to grow to nearly 78 million and ethnic minorities will rise from 8 per cent at the 2001 census to 20 per cent. These are two key conclusions from some research by a team in the geography department at the University of Leeds – a thorough piece of work that should illuminate a debate that has up to now generated more heat than light.

Of course, all population projections are just that: projections rather than forecasts. The imponderables are huge. There have been huge variations in net migration here in the UK over the past 50 years, ranging from a net inflow of 250,000 in 2004, to a net outflow averaging 25,000 a year during the 1970s. Anyone feeling nostalgia for the 1970s should note that people were voting with their feet to get out. But even that was dwarfed by the outflow of people in the early part of the last century: from 1901 to 1931 the average annual outflow was around 75,000.

Birth rates have varied massively, too. In the mid-1960s, the tail end of the post-war baby boom, the UK fertility rate – the number of babies born to each mother – was 2.8, far above the replacement rate of 2.1 babies. By the middle 1990s, that had fallen to below 1.7, while now it has climbed slightly to 1.8. In some other countries the swings have been even more dramatic. For example, in 1965 in Spain the average was just three babies per mother, while by 2000 it was down to below 1.2 babies.

And death rates have changed, too, with life expectancy rising far faster than demographers expected even five or 10 years ago. In any human sense of values, this demographic time-bomb, as it is called, must be good news – you don't actually want people to die younger – but the changing estimates of mortality have played havoc with pension calculations.

So you do have to take the Leeds University projections with a bit of caution. But they have done all the work. They have made different assumptions about migration, about fertility trends of the various ethnic groups (people from the Indian sub-continent tend to have slightly larger families than the white majority), and about population movements within the various regions of the UK. The estimates will inevitably be wrong as to detail but I think we have to accept they will be broadly right.

Indeed, I suggest we have to hope they will be broadly right. Think about reasons why the population might be radically different. A sharp fall in longevity? You have only to look to Russia to see the misery associated with that. A surge in outward migration? That would suggest that many people were unhappy with the state of the country. A collapse in birth rates? Surely that would also suggest a lack of confidence in the future. A collapse in inward migration? That might happen if the economy were to tank and there were no jobs, but I don't think that would be pleasant either.

So we should plan for it. We can think about restricting inward migration and undoubtedly will. It is certainly reasonable that any country should try to attract the migrants that will help society – people who bring skills and entrepreneurship – rather than those who want to bring crime. But we are kidding ourselves if we think we can change the general trend of the numbers. We cannot do anything about migration from the rest of the European Union even if we wanted to, and should in any case feel we must be doing something right if other Europeans want to move here.

Planning for such population growth falls into two broad areas: physical and social. The physical is obvious enough. We have to spend more on infrastructure, on homes and on workplaces, and we have to do so in a way that is environmentally sustainable. We have to make the place nicer to live in. That leads into debates about density. The South-east of England, which is where much of the population growth will inevitably take place, is densely populated by world standards, even if London is no longer one of the largest cities in the world. But there are other densely populated areas, the Netherlands for example, which have managed such growth as well, or better.

We have done some things well but we have a lot to learn. One particular example of planning failure is our home-building programme, building too few homes and too small ones, often crammed on to unsuitable sites. Just yesterday the OECD noted that we should improve our housing market by making "the planning system more flexible, more predictable and provide incentives for local communities to release land for building, while continuing to protect the environment".

The less obvious planning is the social one and there we will have to think about defining rights and responsibilities more precisely. A homogeneous society can rub along with generally accepted social norms. Look at Japan, which has the lowest crime rate in the world, and where social pressures define behaviour, rather than legal ones. By contrast, in the most heterogeneous of Western societies, the US manages by using a mixture of law and regulation as well as social pressures to define how people should behave. It has also been more explicit than we have in getting the message over to migrants that if you want to go there, you have to sign up to the rules of the place. Our last government was already moving in that direction.

In a way, we are lucky. We have a model in the US, Canada, Australia and other culturally similar (well, sort of) societies that have more experience of inward migration than we do. This is not a journey without maps. The task is to learn from others and try to do this well. Surely that is not too much to ask?

h.mcrae@independent.co.uk

For further reading

Leeds University School of Geography: www.geog.leeds.ac.uk