A watershed moment
For something so ephemeral, something that runs elusively through our fingers and prompted our ancestors to worship the gods that brought it, water is surprisingly easy to quantify. The total volume of water on Earth is about 1.4 billion cubic kilometres, according to the UN, of which freshwater resources amount to 35 million cubic kilometres, or about 2.5 per cent of all water.
We also know a lot about the quality, and the amount, of water we’re using – figures that make for unsettling reading. Poor sanitation, a lack of clean drinking water, the vast amounts of water devoted to agriculture, a growing global population and climate change all make access to those precious H2O molecules increasingly fraught. Groundwater- and river-based ecosystems are also deteriorating as extraction rates increase more rapidly than aquifers can be replenished.
Our basic needs, according to the UN, can be met by 1,000 cubic metres of water per person per year. Right now, according to most experts, the world’s six billion people are appropriating 54 per cent of all of the accessible freshwater contained in rivers, lakes and underground aquifers. That leaves 46 per cent untapped; in theory, far more than enough to go round. But this simple mathematics is somewhat removed from a reality where a child dies as a result of poor sanitation every 20 seconds, amounting to 1.5 million preventable deaths each year. One in six people, says the World Health Organization (WHO), don’t have access to safe drinking water.
This pressure is likely to increase, with demand for fresh water predicted to rise by 30 per cent by 2030, according to the International Food Policy Research Institute. Meanwhile, UN Water, a coalition of UN agencies, estimates that by 2020, two thirds of us will experience water shortages; by 2050, seven billion people in 60 countries
may have to cope with water stress.
Access to water is cited, along with energy and food security, as a key component of the ‘perfect storm’ of resource shortages outlined by Professor John Beddington, the UK government’s chief scientist; and geopolitical analysts increasingly argue that the major wars of this century are likely to be fought over water rather than land or fossil fuels. Professor Alan Werritty, research director at the Centre for Water Law, Policy and Science at the University of Dundee, looks at the Green Revolution of the 1960s and ’70s, which sought to increase food production, and concludes that climate change and a growing population make the challenge of providing more water ‘a far more severe scenario’.
Sanitation situation
Rapidly changing demographics are also placing pressure on water supplies, according to Professor Louise Heathwaite, co-director of the Centre for Sustainable Water Management at Lancaster University. ‘People move to cities and many more young people live in their own flats, with higher consumption and higher water demand,’ she says. ‘If you throw climate change into that, with changing rainfall patterns, you have a lot of pressures that are creating hot spots.’
The statistics on basic sanitation are shocking: less than two thirds of the world enjoys basic toilet facilities of the kind that we in the West take for granted, and 1.2 billion have no facilities at all; 18 per cent of the world’s population practises indiscriminate or open defecation – in fields, forests, bushes, lakes and rivers. Open defecation is still most widely practised in southern Asia and sub-Saharan Africa – respectively by 48 per cent and 28 per cent of the population. In India, 665 million people – nearly half the population – openly defecate; in Indonesia, the figure is 66 million; overall, 31 per cent of the world’s rural population practises open defecation. The Millennium Development Goal of halving the proportion of people without basic sanitation by 2015 is, unsurprisingly, way off track.
The news on clean drinking water supplies is better: the WHO and UNICEF say that, for the first time, the number of people without improved drinking water has dropped below one billion, and that more than half of the global population now benefits from piped water reaching their homes. Even so, that leaves a large proportion of humanity – around 884 million people – at significant risk of diarrhoeal diseases, worm infestations, hepatitis and other ailments.
Institutional indifference
Speak to most water experts and, contrary to common perception, they argue that a lack of access to water isn’t the root cause of poor sanitation. ‘Water resources such as rivers and groundwater aren’t always linked to water supplies and sanitation,’ says Anders Berntell, executive director of the Stockholm-based Swedish International Water Institute (SIWI). ‘You can have plenty of water available locally, but people still have difficulty gaining access to safe supplies – and it’s even more the case with sanitation.
‘There are countries where water is very scarce, but in the majority of places, the lack of clean drinking water and sanitation is related to governance and finance,’ he continues. ‘Infrastructure hasn’t been managed, there is no support, there’s improper funding, so the system doesn’t work.’
This lack of funding reflects an institutional indifference to water, according to Alastair Morrison, a water policy advisor for the UN Development Programme. Morrison, who had to defend funding for water sanitation projects when he worked for an NGO, argues that the international community, in the form of inter-governmental and aid organisations and engineers, must shoulder a large degree of the blame. ‘Water is a very low priority for many countries. It’s an unfortunate state of affairs, but it isn’t considered glamorous. It’s a low priority for governments, aid organisations and even local communities,’ he says. ‘Engineers don’t consider it glamorous compared with building big structures. Those of us who do care should be shouting about it more – there haven’t been so many of us arguing for it.’
Morrison’s is far from a lone voice; other experts feel strongly that more passion is required to give momentum to what are often extremely basic remedies. ‘We always look for technological fixes, and there are small things, such as small-scale filtering, that work, but they’ve been around for quite a long time,’ says Heathwaite. ‘It’s more the case that we don’t necessarily value water appropriately, which is strange, given that we tend to die if we don’t get enough of it.’
Most experts are wary of drawing parallels with global food problems (although, as Werritty points out, ‘food security is very closely linked to water security’, and genetically drought-tolerant crops may be required to efficiently utilise our water resources). With water, the emphasis shifts from issues of global trade and towards the local village or community. Inadequate sanitation and drinking water often has as much to do with education and cultural mores as it does with a lack of technology, poverty, poor infrastructure or location. ‘We need to persuade people that it isn’t acceptable to openly defecate,’ says Morrison. ‘For the vast majority of water supply and sanitation problems, it’s a cultural issue, getting people to understand that it’s important, and using peer pressure to secure change. It isn’t about hardware interventions – it’s just that in some countries it’s difficult to talk about “pee and poo”. Cultural issues are important to get programmes moving.’
Other benefits would follow a shift in attitudes to open defecation. ‘A lot of improved sanitation ends up coming from families rather than governments,’ says Morrison. ‘If a village agrees to sanitation, then a local craftsman can make the latrine flaps and screens required, keeping costs down and creating local jobs.’
SIWI supports a local approach called Community-led Total Sanitation, which has been effective in Bangladesh. Villages are able to declare themselves free of open defecation and take influential local decisions, such as forbidding marriages with people from villages where open defecation is still practised. ‘It’s a lot about changing attitudes,’ says Berntell. ‘In many rural areas, you still have a high preference for open defecation among men. They aren’t used to toilets of any sort, and that leads to a continuous spread of disease.’
Poor populations
Poverty remains a major factor in water supplies. Problems with drinking water are worst in sub-Saharan Africa, while sanitation is worst in South and Southeast Asia and again in sub-Saharan Africa. ‘Poverty is still key,’ says Morrison. ‘Countries that have shown substantial economic growth will generally have better water supplies. Extreme poverty, economic migration, HIV, conflict and failed states all make it difficult to improve water quality.’
Yet economic growth doesn’t automatically lead to improved sanitation – despite strong GDP figures in recent years, neither Indonesia nor India has made much progress in improving sanitation. ‘Better sanitation is hugely important for education, the economy, the environment and health,’ says Morrison. ‘Many girls in developing countries won’t be sent to school if there’s no sanitation there because it’s seen as shameful.’
The inclination of the world’s growing population to gravitate to urban areas has rapidly depleted urban aquifers, accelerating the use of wastewater, excreta and grey water for agriculture and aquaculture. In many areas, wastewater is the only source of water available in sufficient quantities throughout the year. But sourcing wastewater for farms on urban fringes, where such water usually contains microbiological contaminants, is an efficient way to make a lot of people very sick, very quickly.
Yet the increased demand for water among poor semi-urban communities has forced the WHO and the UN Food and Agriculture Organization (FAO) to exploit the reuse of drainage water and water of marginal quality, such as treated wastewater and brackish water, especially in arid and semi-arid zones. Leafy vegetables are known to grow well with wastewater, and both the WHO and FAO promote techniques that enable farms to reuse municipal wastewater and sewage sludge, the latter as a free alternative to fertiliser. Up to a level of saturation, soils can assimilate and detoxify pollutants; but it’s an imperfect solution that requires farmers and scientists to keep to set pollutant concentrations. Robert Bos, co-ordinator for water and sanitation at the WHO, concedes that the organisation seeks ‘health-based targets that can be established at a level that is realistic under local conditions’.
Despite reservations – tests of water quality by WHO officials indicate that while heavy metals are within safe limits, there are often high levels of faecal contamination – the system has been shown to work. Techniques to reduce the transmission of excreta-associated diseases include halting irrigation prior to harvesting; the promotion of improved food hygiene and handling; safe washing of vegetables; and the use of disinfectants.
This approach has benefited landless and smallholder households along the Musi River in India’s Andhra Pradesh, who use wastewater from Hyderabad and Secunderabad. Here, the use of canal wastewater irrigation – where water is pumped from branch canals or diverted via weirs into underground pipes – enables the cultivation of vegetables, para grass, palm fronds and banana leaves. In rural areas of the region, wastewater-irrigated paddies contribute almost 43 per cent of household food consumption.
Falling yields
As if all of these pressures weren’t enough, climate change is already significantly altering rainfall patterns and switching the location of where this water falls. The Intergovernmental Panel on Climate Change predicts that yields from rain-dependent agriculture could drop by half by 2020. In sub-Saharan Africa, the FAO reckons that 75 million hectares currently suitable for rain-fed agriculture will be lost.
Climate change could mean good or bad news, depending on where you live: higher temperatures will benefit agriculture in higher latitudes, but in the semi-tropics and in arid regions, large areas will face declining rainfall. According to SIWI, areas that are already dry will become even drier, including the Mediterranean, North Africa, most of the Middle East, the southern USA, California, Mexico and Australia. Meanwhile, more rainfall can be expected in northern Europe, northern USA and Canada. There may even be a few winners: southern India and much of China, Kenya, Uganda, and even parts of sub-Saharan Africa could enjoy increased harvests as more rain falls there.
Changes in rainfall patterns are more difficult to predict than temperature changes, so come with a qualified health warning, but the trends may be capricious. ‘Projections tell us that the annual average rainfall won’t change that dramatically – but that often there will be too much, or too little, or it will be at the wrong time or in the wrong place,’ says Berntell. He points out that shifting patterns could potentially have a devastating impact on established crop patterns. The Indian monsoon appears poised to dramatically illustrate these shifts. ‘A shift in the timing of the Indian monsoon would be equally important as you have an agricultural system where plants are timed for its arrival. You would have serious impacts if it came at a different time.’
Perhaps we need to look at the issue from another angle. Professor Jorg Imberger, of the Centre for Water Research at the University of Western Australia (UWA) in Perth, points out that while some 70 per cent of the continent is covered by desert or semi-arid land, ‘everyone, including almost all Australians, thinks Australia has a problem with water scarcity. But we don’t. Rainfall has receded by 15 per cent in the southeast and 20 per cent in the southwest over the past 20 years, but the upper half of Australia has had considerably more,’ he says. ‘The problem is that most of it soaks into the ground and is absorbed by trees, so there is no run-off.’
One solution, he suggests, is to follow the model of the Aboriginals and the first settlers. ‘Our convicts didn’t set up in the Simpson Desert – they settled where the rains were,’ he says. ‘I’m not suggesting we force people to relocate to where the rains now fall, but if the right tax incentives were in place, with money for good schools and hospitals, you could encourage companies to relocate.’
But such moves may not be necessary, he points out. Perth sits on two aquifers, each of which can provide the region’s water for 1,000 years. ‘We have an essentially infinite amount of resources, but for political reasons, we seem to be happy to spend money on desalination projects instead,’ he says.
Voracious consumer
The stampede to prepare and devise solutions other than wholesale relocation of populations appears to be notable only for its absence. ‘Very few countries – either developed or developing – have started to take action in a structured way to address the issue of adaptation to less water with climate change,’ says Berntell. ‘If they start preparing now, then you improve the possibility of dealing with the challenges we’re facing.’
Ultra-efficient rain harvesting and improved irrigation will be fundamental if we wish to stave off a parched future. ‘In drier areas, it’s about increasing your capacity to store rain,’ says Berntell. ‘That can be either at the local small farmer or house scale, or with large dams and reservoirs. The solutions will need to be quite ingenious.’
Agriculture is by far the most voracious consumer of water, described by Werritty as ‘the real villain of the piece’. Irrigation claims close to 70 per cent of all fresh water appropriated for human use, and in sub-Saharan Africa, this figure is 87 per cent, according to the FAO. Around 277 million hectares, about 20 per cent of all cropland,
is under irrigation, and rain-fed agriculture accounts for the remaining 80 per cent.
Israel is at the forefront of efforts to make agriculture more efficient, taking an intensive water management approach, employing sub-surface drip irrigation that feeds water directly to the plant’s roots, rather than pouring water onto hot soil, where it will quickly evaporate. Yet such techniques are expensive and still may not be enough.
‘Many societies in water-scarce areas have devised quite sophisticated techniques to gain access to water, but because of urbanisation, many of those techniques are under stress and it’s likely that some will struggle to maintain these practices,’ says Werritty. ‘Even Israel is pushing hard up against all sorts of buffers. Some experts would say that Israel has to get out of food production and use its water for human consumption and industrial needs rather than using an enormous amount on soft foods. But there are consequences with that, so it’s not a silver bullet.’
Israel may join other water-scarce countries in forsaking food production and embracing the concept of ‘virtual water’. ‘Some nations will have to give up their emphasis of national food security,’ says Berntell. ‘They will have to rely on imports of food. Several Gulf states have already taken the decision to use their scarce water for other purposes and either buy their food on the world market or outsource food production.’
Time for change
For now, however, many nations simply have so much water they perceive no need to change. ‘You still see farmers spraying their crops in the heat of the day and much of the water evaporates before it even enters the soil,’ says Berntell. ‘You don’t need to be an engineer – it’s about governance. Farmers everywhere are subsidised to spray water and that gives them no incentive to change their practices.’
Reforestation will also help, argues UWA’s Imberger, who has created models that suggest that reforestation of southwest Australia would recover 60 per cent of the rain loss of the past two decades. ‘If we reforested the southwest, we would fill our reservoirs up again. When you replant trees from the ocean inland, the rains come in much further. When you clear those forests, the rain stops.’
Cutting the amount we waste will underpin any chance of success. ‘We waste an enormous amount of water,’ says Werritty. ‘The traditional predict-and-supply approach has been incredibly wasteful. The key is integrating water resources – fixing leaks, lining reservoirs and reducing consumption.’
Pricing will also have its place, although Werritty acknowledges that this mustn’t affect people on lower incomes. ‘Water can be regarded as a human right,’ he says. ‘It’s a huge challenge for public education, and for pricing water to make people sensitive to its use. If we get that right, then it’s not impossible that we may fix many of these challenges.’
Unlike food security, with its huge logistical challenges and questions of whether genetic modification is necessary to feed us all, water shortages and poor water quality appear to be obstacles that can be surmounted with willingness and funding. ‘I’m optimistic that just about everyone will have access to clean water and sanitation,’ says Berntell. ‘By and large, it’s a management and financial problem. It’s not a law of nature. It’s something we can fix within the existing system if politicians take the right attitude.’
Whether the world can rustle up that willingness is far from guaranteed. ‘If we start thinking and planning in a more integrated way now, we may find a more sustainable solution,’ says Heathwaite. ‘The longer we leave it, the more complex it will be.’
Alternatives to desalination
Desalination is often cited as the answer to our water problems: after all, there’s almost 1.4 billion cubic metres of salt water out there.
But the high cost of desalination – the UK’s Environment Agency reckons converting salt water into potable form costs ten times as much as treating the equivalent quantity of groundwater – has prompted governments to consider alternatives, encouraged by the knowledge that filtration technology now means there’s little that can’t be purified.
Faced with paying higher costs for imported water and desalination, Singapore has pursued a path towards water self-sufficiency, a policy that relies significantly on treated sewage water. The concept of drinking toilet-bowl water may sound unpalatable to some, but Singapore’s treated water – cleaned by a combination of dual-membrane technology (microfiltration and reverse osmosis) and ultraviolet disinfection – exceeds WHO standards. Branded as Newater, this treated wastewater now takes its place alongside rainwater catchments, imports and desalination as a key source of water for the island city state.
The emphasis on Newater came after Malaysia suggested that it would stop selling low-cost untreated water to Singapore next year and instead supply filtered water at higher cost. Malaysian imports accounted for around half of Singapore’s water ten years ago, but that figure has since been reduced to 40 per cent with the expansion of Newater, a desalination plant that produces 136,000 cubic metres of water a day, and the controversial damming of the Singapore River near its mouth.
By the end of this year, when a fifth Newater plant opens, treated water sourced from flushed toilets will account for around 30 per cent of Singapore’s drinking water.
Stressful times in the UK
British readers would be wrong to assume that the question of water shortages is irrelevant in a country where the favourite topic of conversation is the weather. According to the FAO, the average annual water availability per person in the UK is around 2,465 cubic metres, less than Spain (2,794 cubic metres), Italy (3,325 cubic metres) and France (3,439 cubic metres).
Professor Louise Heathwaite points out that average annual rainfall in the UK is unevenly distributed, and in Southeast England, the lower effective rainfall of 260 millimetres, combined with a high population density (425 people per square kilometre, compared with the UK average of 240 people per square kilometre), gives an average of 610 cubic metres of water per person per year, which is less than Egypt (859 cubic metres). The available water resource per head of population in the Southeast is about half of the figure used by the World Bank to indicate that a country is suffering water stress.
The South East Plan, prepared by the South East England Regional Assembly, proposes to increase the population of the region by about one million by 2026, which will place enormous pressure on the Thames and Hampshire basins and the Weald.
Saving the Murray-Darling
The Murray-Darling Basin is often described as Australia’s food bowl, producing 40 per cent of the country’s grain, fruit and vegetables. The River Darling runs from Queensland to South Australia, while the Murray forms the border between Victoria and New South Wales; the basin covers a total area of 1,061,469 square kilometres (14 per cent of the total land mass of Australia).
Today, the basin is under inordinate stress, from a combination of historical use for agriculture, natural climate variability, prolonged drought and, now, climate change. The river basin uses 13,000 gigalitres of water every year – in comparison, Melbourne and Sydney combined use just two gigalitres. In New South Wales, 82 per cent of the available water from the basin is already utilised. The most optimistic climate change scenario, calculated by the Commonwealth Scientific and Industrial Research Organisation, suggests that by 2030, the average water availability will have been reduced by nine per cent.
Within the next 18 months, a major operation to resuscitate the rivers will begin, with the implementation of a basin-wide sustainable management plan. The intention is to limit the amount of surface water and groundwater that can be taken from basin water resources, as well as managing water quality and salinity. The federal government will buy land from farmers, releasing water to run down the river. The plan will set sustainable diversion limits: current limits are set on historical use, not on sustainable use. There will also be an environmental watering plan to restore and sustain the wetlands that depend on the rivers.
Percentage of freshwater withdrawal that is used for agriculture
Somalia: 98
Cambodia: 98
Portugal: 78
China: 68
Israel: 58
USA: 41
Germany: 20
Russia: 18
UK: 3
Iceland: 0
Percentage of cropland under irrigation
Egypt: 100
Somalia: 99
India: 86
Australia: 75
China: 68
Costa Rica: 53
USA: 41
Hungary: 32
Belize: 20
Canada: 12
UK: 3
Ireland: 0
Total annual renewable water resources (cubic metres/capita)
Greenland: 10,767,857
Guyana: 316,689
Canada: 94,353
Australia: 25,708
Mongolia: 13,739
Greece: 6,998
Mexico: 4,624
UK: 2,465
India: 1,880
Denmark: 1,128
Egypt: 859
Rwanda: 683
Yemen: 223
Maldives: 103
Kuwait: 10
April 2010
We also know a lot about the quality, and the amount, of water we’re using – figures that make for unsettling reading. Poor sanitation, a lack of clean drinking water, the vast amounts of water devoted to agriculture, a growing global population and climate change all make access to those precious H2O molecules increasingly fraught. Groundwater- and river-based ecosystems are also deteriorating as extraction rates increase more rapidly than aquifers can be replenished.
Our basic needs, according to the UN, can be met by 1,000 cubic metres of water per person per year. Right now, according to most experts, the world’s six billion people are appropriating 54 per cent of all of the accessible freshwater contained in rivers, lakes and underground aquifers. That leaves 46 per cent untapped; in theory, far more than enough to go round. But this simple mathematics is somewhat removed from a reality where a child dies as a result of poor sanitation every 20 seconds, amounting to 1.5 million preventable deaths each year. One in six people, says the World Health Organization (WHO), don’t have access to safe drinking water.
This pressure is likely to increase, with demand for fresh water predicted to rise by 30 per cent by 2030, according to the International Food Policy Research Institute. Meanwhile, UN Water, a coalition of UN agencies, estimates that by 2020, two thirds of us will experience water shortages; by 2050, seven billion people in 60 countries
may have to cope with water stress.
Access to water is cited, along with energy and food security, as a key component of the ‘perfect storm’ of resource shortages outlined by Professor John Beddington, the UK government’s chief scientist; and geopolitical analysts increasingly argue that the major wars of this century are likely to be fought over water rather than land or fossil fuels. Professor Alan Werritty, research director at the Centre for Water Law, Policy and Science at the University of Dundee, looks at the Green Revolution of the 1960s and ’70s, which sought to increase food production, and concludes that climate change and a growing population make the challenge of providing more water ‘a far more severe scenario’.
Sanitation situation
Rapidly changing demographics are also placing pressure on water supplies, according to Professor Louise Heathwaite, co-director of the Centre for Sustainable Water Management at Lancaster University. ‘People move to cities and many more young people live in their own flats, with higher consumption and higher water demand,’ she says. ‘If you throw climate change into that, with changing rainfall patterns, you have a lot of pressures that are creating hot spots.’
The statistics on basic sanitation are shocking: less than two thirds of the world enjoys basic toilet facilities of the kind that we in the West take for granted, and 1.2 billion have no facilities at all; 18 per cent of the world’s population practises indiscriminate or open defecation – in fields, forests, bushes, lakes and rivers. Open defecation is still most widely practised in southern Asia and sub-Saharan Africa – respectively by 48 per cent and 28 per cent of the population. In India, 665 million people – nearly half the population – openly defecate; in Indonesia, the figure is 66 million; overall, 31 per cent of the world’s rural population practises open defecation. The Millennium Development Goal of halving the proportion of people without basic sanitation by 2015 is, unsurprisingly, way off track.
The news on clean drinking water supplies is better: the WHO and UNICEF say that, for the first time, the number of people without improved drinking water has dropped below one billion, and that more than half of the global population now benefits from piped water reaching their homes. Even so, that leaves a large proportion of humanity – around 884 million people – at significant risk of diarrhoeal diseases, worm infestations, hepatitis and other ailments.
Institutional indifference
Speak to most water experts and, contrary to common perception, they argue that a lack of access to water isn’t the root cause of poor sanitation. ‘Water resources such as rivers and groundwater aren’t always linked to water supplies and sanitation,’ says Anders Berntell, executive director of the Stockholm-based Swedish International Water Institute (SIWI). ‘You can have plenty of water available locally, but people still have difficulty gaining access to safe supplies – and it’s even more the case with sanitation.
‘There are countries where water is very scarce, but in the majority of places, the lack of clean drinking water and sanitation is related to governance and finance,’ he continues. ‘Infrastructure hasn’t been managed, there is no support, there’s improper funding, so the system doesn’t work.’
This lack of funding reflects an institutional indifference to water, according to Alastair Morrison, a water policy advisor for the UN Development Programme. Morrison, who had to defend funding for water sanitation projects when he worked for an NGO, argues that the international community, in the form of inter-governmental and aid organisations and engineers, must shoulder a large degree of the blame. ‘Water is a very low priority for many countries. It’s an unfortunate state of affairs, but it isn’t considered glamorous. It’s a low priority for governments, aid organisations and even local communities,’ he says. ‘Engineers don’t consider it glamorous compared with building big structures. Those of us who do care should be shouting about it more – there haven’t been so many of us arguing for it.’
Morrison’s is far from a lone voice; other experts feel strongly that more passion is required to give momentum to what are often extremely basic remedies. ‘We always look for technological fixes, and there are small things, such as small-scale filtering, that work, but they’ve been around for quite a long time,’ says Heathwaite. ‘It’s more the case that we don’t necessarily value water appropriately, which is strange, given that we tend to die if we don’t get enough of it.’
Most experts are wary of drawing parallels with global food problems (although, as Werritty points out, ‘food security is very closely linked to water security’, and genetically drought-tolerant crops may be required to efficiently utilise our water resources). With water, the emphasis shifts from issues of global trade and towards the local village or community. Inadequate sanitation and drinking water often has as much to do with education and cultural mores as it does with a lack of technology, poverty, poor infrastructure or location. ‘We need to persuade people that it isn’t acceptable to openly defecate,’ says Morrison. ‘For the vast majority of water supply and sanitation problems, it’s a cultural issue, getting people to understand that it’s important, and using peer pressure to secure change. It isn’t about hardware interventions – it’s just that in some countries it’s difficult to talk about “pee and poo”. Cultural issues are important to get programmes moving.’
Other benefits would follow a shift in attitudes to open defecation. ‘A lot of improved sanitation ends up coming from families rather than governments,’ says Morrison. ‘If a village agrees to sanitation, then a local craftsman can make the latrine flaps and screens required, keeping costs down and creating local jobs.’
SIWI supports a local approach called Community-led Total Sanitation, which has been effective in Bangladesh. Villages are able to declare themselves free of open defecation and take influential local decisions, such as forbidding marriages with people from villages where open defecation is still practised. ‘It’s a lot about changing attitudes,’ says Berntell. ‘In many rural areas, you still have a high preference for open defecation among men. They aren’t used to toilets of any sort, and that leads to a continuous spread of disease.’
Poor populations
Poverty remains a major factor in water supplies. Problems with drinking water are worst in sub-Saharan Africa, while sanitation is worst in South and Southeast Asia and again in sub-Saharan Africa. ‘Poverty is still key,’ says Morrison. ‘Countries that have shown substantial economic growth will generally have better water supplies. Extreme poverty, economic migration, HIV, conflict and failed states all make it difficult to improve water quality.’
Yet economic growth doesn’t automatically lead to improved sanitation – despite strong GDP figures in recent years, neither Indonesia nor India has made much progress in improving sanitation. ‘Better sanitation is hugely important for education, the economy, the environment and health,’ says Morrison. ‘Many girls in developing countries won’t be sent to school if there’s no sanitation there because it’s seen as shameful.’
The inclination of the world’s growing population to gravitate to urban areas has rapidly depleted urban aquifers, accelerating the use of wastewater, excreta and grey water for agriculture and aquaculture. In many areas, wastewater is the only source of water available in sufficient quantities throughout the year. But sourcing wastewater for farms on urban fringes, where such water usually contains microbiological contaminants, is an efficient way to make a lot of people very sick, very quickly.
Yet the increased demand for water among poor semi-urban communities has forced the WHO and the UN Food and Agriculture Organization (FAO) to exploit the reuse of drainage water and water of marginal quality, such as treated wastewater and brackish water, especially in arid and semi-arid zones. Leafy vegetables are known to grow well with wastewater, and both the WHO and FAO promote techniques that enable farms to reuse municipal wastewater and sewage sludge, the latter as a free alternative to fertiliser. Up to a level of saturation, soils can assimilate and detoxify pollutants; but it’s an imperfect solution that requires farmers and scientists to keep to set pollutant concentrations. Robert Bos, co-ordinator for water and sanitation at the WHO, concedes that the organisation seeks ‘health-based targets that can be established at a level that is realistic under local conditions’.
Despite reservations – tests of water quality by WHO officials indicate that while heavy metals are within safe limits, there are often high levels of faecal contamination – the system has been shown to work. Techniques to reduce the transmission of excreta-associated diseases include halting irrigation prior to harvesting; the promotion of improved food hygiene and handling; safe washing of vegetables; and the use of disinfectants.
This approach has benefited landless and smallholder households along the Musi River in India’s Andhra Pradesh, who use wastewater from Hyderabad and Secunderabad. Here, the use of canal wastewater irrigation – where water is pumped from branch canals or diverted via weirs into underground pipes – enables the cultivation of vegetables, para grass, palm fronds and banana leaves. In rural areas of the region, wastewater-irrigated paddies contribute almost 43 per cent of household food consumption.
Falling yields
As if all of these pressures weren’t enough, climate change is already significantly altering rainfall patterns and switching the location of where this water falls. The Intergovernmental Panel on Climate Change predicts that yields from rain-dependent agriculture could drop by half by 2020. In sub-Saharan Africa, the FAO reckons that 75 million hectares currently suitable for rain-fed agriculture will be lost.
Climate change could mean good or bad news, depending on where you live: higher temperatures will benefit agriculture in higher latitudes, but in the semi-tropics and in arid regions, large areas will face declining rainfall. According to SIWI, areas that are already dry will become even drier, including the Mediterranean, North Africa, most of the Middle East, the southern USA, California, Mexico and Australia. Meanwhile, more rainfall can be expected in northern Europe, northern USA and Canada. There may even be a few winners: southern India and much of China, Kenya, Uganda, and even parts of sub-Saharan Africa could enjoy increased harvests as more rain falls there.
Changes in rainfall patterns are more difficult to predict than temperature changes, so come with a qualified health warning, but the trends may be capricious. ‘Projections tell us that the annual average rainfall won’t change that dramatically – but that often there will be too much, or too little, or it will be at the wrong time or in the wrong place,’ says Berntell. He points out that shifting patterns could potentially have a devastating impact on established crop patterns. The Indian monsoon appears poised to dramatically illustrate these shifts. ‘A shift in the timing of the Indian monsoon would be equally important as you have an agricultural system where plants are timed for its arrival. You would have serious impacts if it came at a different time.’
Perhaps we need to look at the issue from another angle. Professor Jorg Imberger, of the Centre for Water Research at the University of Western Australia (UWA) in Perth, points out that while some 70 per cent of the continent is covered by desert or semi-arid land, ‘everyone, including almost all Australians, thinks Australia has a problem with water scarcity. But we don’t. Rainfall has receded by 15 per cent in the southeast and 20 per cent in the southwest over the past 20 years, but the upper half of Australia has had considerably more,’ he says. ‘The problem is that most of it soaks into the ground and is absorbed by trees, so there is no run-off.’
One solution, he suggests, is to follow the model of the Aboriginals and the first settlers. ‘Our convicts didn’t set up in the Simpson Desert – they settled where the rains were,’ he says. ‘I’m not suggesting we force people to relocate to where the rains now fall, but if the right tax incentives were in place, with money for good schools and hospitals, you could encourage companies to relocate.’
But such moves may not be necessary, he points out. Perth sits on two aquifers, each of which can provide the region’s water for 1,000 years. ‘We have an essentially infinite amount of resources, but for political reasons, we seem to be happy to spend money on desalination projects instead,’ he says.
Voracious consumer
The stampede to prepare and devise solutions other than wholesale relocation of populations appears to be notable only for its absence. ‘Very few countries – either developed or developing – have started to take action in a structured way to address the issue of adaptation to less water with climate change,’ says Berntell. ‘If they start preparing now, then you improve the possibility of dealing with the challenges we’re facing.’
Ultra-efficient rain harvesting and improved irrigation will be fundamental if we wish to stave off a parched future. ‘In drier areas, it’s about increasing your capacity to store rain,’ says Berntell. ‘That can be either at the local small farmer or house scale, or with large dams and reservoirs. The solutions will need to be quite ingenious.’
Agriculture is by far the most voracious consumer of water, described by Werritty as ‘the real villain of the piece’. Irrigation claims close to 70 per cent of all fresh water appropriated for human use, and in sub-Saharan Africa, this figure is 87 per cent, according to the FAO. Around 277 million hectares, about 20 per cent of all cropland,
is under irrigation, and rain-fed agriculture accounts for the remaining 80 per cent.
Israel is at the forefront of efforts to make agriculture more efficient, taking an intensive water management approach, employing sub-surface drip irrigation that feeds water directly to the plant’s roots, rather than pouring water onto hot soil, where it will quickly evaporate. Yet such techniques are expensive and still may not be enough.
‘Many societies in water-scarce areas have devised quite sophisticated techniques to gain access to water, but because of urbanisation, many of those techniques are under stress and it’s likely that some will struggle to maintain these practices,’ says Werritty. ‘Even Israel is pushing hard up against all sorts of buffers. Some experts would say that Israel has to get out of food production and use its water for human consumption and industrial needs rather than using an enormous amount on soft foods. But there are consequences with that, so it’s not a silver bullet.’
Israel may join other water-scarce countries in forsaking food production and embracing the concept of ‘virtual water’. ‘Some nations will have to give up their emphasis of national food security,’ says Berntell. ‘They will have to rely on imports of food. Several Gulf states have already taken the decision to use their scarce water for other purposes and either buy their food on the world market or outsource food production.’
Time for change
For now, however, many nations simply have so much water they perceive no need to change. ‘You still see farmers spraying their crops in the heat of the day and much of the water evaporates before it even enters the soil,’ says Berntell. ‘You don’t need to be an engineer – it’s about governance. Farmers everywhere are subsidised to spray water and that gives them no incentive to change their practices.’
Reforestation will also help, argues UWA’s Imberger, who has created models that suggest that reforestation of southwest Australia would recover 60 per cent of the rain loss of the past two decades. ‘If we reforested the southwest, we would fill our reservoirs up again. When you replant trees from the ocean inland, the rains come in much further. When you clear those forests, the rain stops.’
Cutting the amount we waste will underpin any chance of success. ‘We waste an enormous amount of water,’ says Werritty. ‘The traditional predict-and-supply approach has been incredibly wasteful. The key is integrating water resources – fixing leaks, lining reservoirs and reducing consumption.’
Pricing will also have its place, although Werritty acknowledges that this mustn’t affect people on lower incomes. ‘Water can be regarded as a human right,’ he says. ‘It’s a huge challenge for public education, and for pricing water to make people sensitive to its use. If we get that right, then it’s not impossible that we may fix many of these challenges.’
Unlike food security, with its huge logistical challenges and questions of whether genetic modification is necessary to feed us all, water shortages and poor water quality appear to be obstacles that can be surmounted with willingness and funding. ‘I’m optimistic that just about everyone will have access to clean water and sanitation,’ says Berntell. ‘By and large, it’s a management and financial problem. It’s not a law of nature. It’s something we can fix within the existing system if politicians take the right attitude.’
Whether the world can rustle up that willingness is far from guaranteed. ‘If we start thinking and planning in a more integrated way now, we may find a more sustainable solution,’ says Heathwaite. ‘The longer we leave it, the more complex it will be.’
Alternatives to desalination
Desalination is often cited as the answer to our water problems: after all, there’s almost 1.4 billion cubic metres of salt water out there.
But the high cost of desalination – the UK’s Environment Agency reckons converting salt water into potable form costs ten times as much as treating the equivalent quantity of groundwater – has prompted governments to consider alternatives, encouraged by the knowledge that filtration technology now means there’s little that can’t be purified.
Faced with paying higher costs for imported water and desalination, Singapore has pursued a path towards water self-sufficiency, a policy that relies significantly on treated sewage water. The concept of drinking toilet-bowl water may sound unpalatable to some, but Singapore’s treated water – cleaned by a combination of dual-membrane technology (microfiltration and reverse osmosis) and ultraviolet disinfection – exceeds WHO standards. Branded as Newater, this treated wastewater now takes its place alongside rainwater catchments, imports and desalination as a key source of water for the island city state.
The emphasis on Newater came after Malaysia suggested that it would stop selling low-cost untreated water to Singapore next year and instead supply filtered water at higher cost. Malaysian imports accounted for around half of Singapore’s water ten years ago, but that figure has since been reduced to 40 per cent with the expansion of Newater, a desalination plant that produces 136,000 cubic metres of water a day, and the controversial damming of the Singapore River near its mouth.
By the end of this year, when a fifth Newater plant opens, treated water sourced from flushed toilets will account for around 30 per cent of Singapore’s drinking water.
Stressful times in the UK
British readers would be wrong to assume that the question of water shortages is irrelevant in a country where the favourite topic of conversation is the weather. According to the FAO, the average annual water availability per person in the UK is around 2,465 cubic metres, less than Spain (2,794 cubic metres), Italy (3,325 cubic metres) and France (3,439 cubic metres).
Professor Louise Heathwaite points out that average annual rainfall in the UK is unevenly distributed, and in Southeast England, the lower effective rainfall of 260 millimetres, combined with a high population density (425 people per square kilometre, compared with the UK average of 240 people per square kilometre), gives an average of 610 cubic metres of water per person per year, which is less than Egypt (859 cubic metres). The available water resource per head of population in the Southeast is about half of the figure used by the World Bank to indicate that a country is suffering water stress.
The South East Plan, prepared by the South East England Regional Assembly, proposes to increase the population of the region by about one million by 2026, which will place enormous pressure on the Thames and Hampshire basins and the Weald.
Saving the Murray-Darling
The Murray-Darling Basin is often described as Australia’s food bowl, producing 40 per cent of the country’s grain, fruit and vegetables. The River Darling runs from Queensland to South Australia, while the Murray forms the border between Victoria and New South Wales; the basin covers a total area of 1,061,469 square kilometres (14 per cent of the total land mass of Australia).
Today, the basin is under inordinate stress, from a combination of historical use for agriculture, natural climate variability, prolonged drought and, now, climate change. The river basin uses 13,000 gigalitres of water every year – in comparison, Melbourne and Sydney combined use just two gigalitres. In New South Wales, 82 per cent of the available water from the basin is already utilised. The most optimistic climate change scenario, calculated by the Commonwealth Scientific and Industrial Research Organisation, suggests that by 2030, the average water availability will have been reduced by nine per cent.
Within the next 18 months, a major operation to resuscitate the rivers will begin, with the implementation of a basin-wide sustainable management plan. The intention is to limit the amount of surface water and groundwater that can be taken from basin water resources, as well as managing water quality and salinity. The federal government will buy land from farmers, releasing water to run down the river. The plan will set sustainable diversion limits: current limits are set on historical use, not on sustainable use. There will also be an environmental watering plan to restore and sustain the wetlands that depend on the rivers.
Percentage of freshwater withdrawal that is used for agriculture
Somalia: 98
Cambodia: 98
Portugal: 78
China: 68
Israel: 58
USA: 41
Germany: 20
Russia: 18
UK: 3
Iceland: 0
Percentage of cropland under irrigation
Egypt: 100
Somalia: 99
India: 86
Australia: 75
China: 68
Costa Rica: 53
USA: 41
Hungary: 32
Belize: 20
Canada: 12
UK: 3
Ireland: 0
Total annual renewable water resources (cubic metres/capita)
Greenland: 10,767,857
Guyana: 316,689
Canada: 94,353
Australia: 25,708
Mongolia: 13,739
Greece: 6,998
Mexico: 4,624
UK: 2,465
India: 1,880
Denmark: 1,128
Egypt: 859
Rwanda: 683
Yemen: 223
Maldives: 103
Kuwait: 10
April 2010
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