Water.
As the Indian population grows, from a resource point of view, the biggest difficulty undoubtedly will be water.
This is what Professor Robert Cassen reveals in his new book, 21st Century India: Population, Economy, Human Development and the Environment, written along with Robert Dyson and and Leela Visaria.
Currently a visiting professor at the London School of Economics, he was previously professor of development economics at Oxford. He has also worked for the British aid programme in New Delhi and on the India desk at the World Bank, and served on the secretariat of the Brandt Commission on North-South issues.
In an e-mail interview with Senior Associate Editor Archana Masih, he says China's "one child family" programme cannot be a kind of model for India as it has had unfortunate consequences for China itself.
How would you compare the rise in India's population with China's?
India's population has been growing somewhat more rapidly in recent decades and fertility decline has come more slowly, but the country's rate of growth is now converging with China's and both should stop growing in the second half of this century.
You say India will overtake China as the most populous country by the middle of this century, does this mean India's population control programme has been a failure?
'Population control' is a phrase few people use, or should use, these days. Bearing and raising children is a private and personal matter; the state should only offer people the means to limit their families and give encouragement it is up to them whether they make use of them or not.
Where has it gone wrong?
The Indian health and family welfare programme has been uneven in its coverage, and the most general criticism is that it has not brought an adequate range of contraceptive measures even to those who want them, with services of good quality. But it is well known that parents' desires for children respond to a large range of factors.
People do not just want babies, but surviving children, so the first thing is that they must be confident about their children's health.
Education and women's welfare -- including later marriages -- are vitally important too, and had India made the same strides in these throughout India as it has in, say, Kerala and Tamil Nadu, the birth rate would undoubtedly have come down faster.
How would you assess India's population control programme? What have been its successes and failures?
Again, we would rather not talk about a "control programme." The successes of India's family welfare programme have been to bring knowledge of contraception and a limited range of measures to a very large number of people.
Its failures have been in the past concentration on "campaigns" related to one measure or another -- the IUD, vasectomy, and female sterilisation, with periodic modest efforts on the condom front.
It is unfortunate that there has been so much concentration on female sterilisation, which is today the main preventer of births in the programme, rather than offering more help for later births and birth spacing.
Are there any measures China is taking successfully that India isn't?
We do not think China's "one child family" programme is any kind of model for India; it has had unfortunate consequences for China itself, and many believe China could have achieved a similar pace of fertility decline by less drastic means.
China has, though, been much more successful than India in controlling communicable diseases, improving nutrition, hygiene and sanitation, and educating all its people -- all of which would have helped India to achieve a more slowly growing population.
If yes, how difficult is it for India to take those measures when one compares India -- a democracy to China, a totalitarian state?
You tell us! India has now been independent for 57 years, but only two-thirds of the population is literate. Did India need to be totalitarian to do better? To control malaria? To bring good-quality reproductive health services and contraception to the great majority of its people?
Your research reveals that India's population will be 1.4 billion by 2026, what implications would this have on the country and its resources?
The implications will be considerable -- our new book spells out many of them. One that we raise but do not answer is how democracy in India can be made fully representative with such large numbers, especially in the large Northern states.
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On the resource front we do not believe any of India's future problems are insuperable -- but achieving increasing prosperity and a cleaner environment at the same time will undoubtedly be difficult, and some of the issues need attention now rather than 25 years from now.
The research also reveals that in the next 25 years more than half of India's demographic growth will be in the states of Uttar Pradesh, Bihar, Madhya Pradesh and Rajasthan -- what are the reasons for this? Is it poverty and illiteracy or are there other factors as well?
Fertility is higher in these states, and the family welfare programme weaker; in addition, all the things that accompany fertility decline -- child survival, education, women's welfare -- are lagging behind the rest of the country.
There is the success of the South Indian states in controlling population -- apart from being an educated people what has the South done that the North couldn't?
The welfare programme is better organised there.
What are the greatest threats in terms of resources, infrastructure and opportunities that India is going to face when it reaches the 1.4 billion mark?
We think the biggest problem socially is the divergence between the South and West and the North and East in economic welfare and in demographics.
In the main the parts of India which are poor and growing slowly economically are growing fast demographically. From a resource point of view, the biggest difficulty undoubtedly lies in water. More people need more water, and there isn't going to be any more in fact if water pollution is not controlled better, there will be even less to go round. India has to achieve much greater water efficiency and that means tough decisions that politicians will not find easy.
Our book suggests that other pollution problems are more manageable, such as those from growing energy use, industry and modern transport. But they have to be managed. Delhi has shown part of the way in beginning to reduce pollution from vehicle traffic, but other cities have yet to follow Delhi's example.
What is the likely scenario when a country is largely dominated by an ageing population?
There are potential economic benefits from declining birth rates, mainly because of a reduction in what is called the "dependency ratio," the proportion of non-workers to workers in the population.
India has about thirty years to enjoy this; then it goes into reverse as the population starts to age. In the rich countries today where ageing has already begun, a particular burden arises from health costs -- a huge proportion of all the lifetime expenditure people incur on their health happens in the years from 60 to 80.
And economic support for the old needs to be provided -- it will be even harder for developing countries, which will go through the ageing process at much lower income levels than in the rich countries.
There is already a huge gulf between the rich and poor. How will a further rise in population affect this? There is a view that the next biggest social problem before Indians would be the battle between the haves and the have nots. How real and grave is this problem?
It is very real. For example, in Kerala and Tamil Nadu, which already have good records in schooling, the school-age population is already shrinking.
In Bihar and UP, where so many children lack education today, the school-age population will still be growing in 2026.
Similar calculations apply to the population of labour-force age in different parts of the country, with implications for employment, and perhaps for migration between states.
So far as population growth is concerned, is it too late for India now?
Of course not. Population growth is slowing down; and manageable if difficult problems lie ahead. The important thing is to see what has to be done now to cope with the challenges of the future.
What in your opinion would be a model that would work for India in the present context?
We do not think India needs another "model." Countless government, NGO and private bodies have already researched and discussed in policy papers virtually all the things that need to be done. It would be nice if some of them were done!
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