The UK's growing population, a rising number of older people and an increase in households with fewer people in them is putting the environment under intense strain, a report warned on Wednesday.
Shifts in the demographics of Britain have created "crunch points" in the south-east and other urban centres, with water supplies, air quality and waste management all suffering from the impact of greater demand and consumption.
The cost of fixing Britain's environmental problems will soar without fresh efforts to reduce waste, use less resources and draw people to less populated areas, the authors add.
The consequences of Britain's shifting population are outlined in a report from the royal commission on environmental pollution entitled Demographic Change and the Environment. It is the last document to be published by the quango before it is scrapped next month to save money.
The report dismisses a claim by the charity, the Optimum Population Trust, that Britain's best hope of achieving environmental sustainability is to reduce the population by more than half to 30 million people.
"We're saying that's absolute nonsense," said Sir John Lawton, chair of the commission. "Even if it were possible or desirable to reduce the birth rate, halt the trend for people to live longer, or achieve zero net migration, there would be little significant reduction in the population of the UK over the next 40 years."
Britain's population is expected to reach 71.6 million in 2033, rising from 61.9 million in 2009, according to the Office of National Statistics. At the same time, the Department of Work and Pensions predicts a significant increase in the number of people over 65, with nearly one in five people alive today expected to see their 100th birthday. The number of households is on the rise too, from 21.5 million in 2006 to an estimated 27.8 million in 2031.
Many demographic changes have both positive and negative impacts on the environment. People over 65 typically use more energy to heat their homes, but they travel far less than younger people, for example. And while larger households use more electricity, gas and water, per capita consumption is low because people share more.
According to the report, household size, the age structure of the population, and where people live have a greater impact on the environment than the size of the population itself. The report urges ministers to invest in job creation schemes in less populated areas, the cost of which can be offset by cheaper prices for land and resources outside urban centres. In practice, there was little the government could do to have any real effect on the size of the population over the next 40 years, the report adds.
While the commission stopped short of recommending compulsory water metering in areas where water is in scarce supply, Lawton's own view was that every household should be fitted with a meter. Installing water meters has been shown to reduce usage by 10-15%, as people pay more attention to the amount of water they are using.
"We don't think government is giving anything like enough attention to demographic change," Lawton said. "And critically if it doesn't, the problems which emerge will cost more in the long run."