One of the World's great environmental problems - Water
The water problem is today one of the greatest problems the world faces. The UN
calculates that if the present development continues the 2/3 of the world population
will live with serious water scarcity or nearly without water by the year 2025. The
UN calculates that one should have 100 litres of water pr day to manage. This is for
everything - home consumption, agriculture, industry, etc. Many people today have
less than 50 litres, and in a country like Mozambique there is only 20 litres of water
for each person pr day. Those 20 litres are the sum of the water taken from boreholes,
rivers and lakes.
We already use over half of all the freshwater, which is available in all the world's
rivers, lakes and groundwater, and the UN calculates that this figure is up between 70
and 90 % in the year 2025, unless something radical is done to change this
development.
The problem is that more water is used than what is returned to the freshwater
systems. The large water consuming areas - USA, China, India, North Africa and the
Arabian Peninsula for example use so much water that their water reserves every year
are depleted of an amount of water which corresponds to the double of the water
running in the Nile - (160 billion m3).
Most of the water is used for agriculture - over 70 % of the consumption. For every
kilo of rice, wheat or maize over 1000 litres of water are used.
At the World Summit for Sustainable Development in Johannesburg last year the
water problem was one of the only issues where a decision was reached - that the
amount of people without access to clean water should be halved by the year 2015. It
is between 800 million and 1 billion people who do not have clean water. This means
that many die of the accompanying diseases. Between 3 and 4 million people - mostly
children - die every year because of water borne diseases. These are diseases spread
by contaminated water such as diarrhoea and cholera, and for example malaria which
is spread by mosquito, whose larvae live in water.
Besides the large amount who die directly because of these diseases, unclean water is
also indirectly causing many deaths. This is because people's immune system is
weakened when they are sick or for example having worms. The large part of people
in Southern Africa have worms because of unclean water. When the immune system
is weakened it is much more likely to be infected with HIV. This is one of the main
reasons that HIV has spread so fast in Southern Africa.
The problem is actually simple to solve. In Africa there is maybe 100.000 villages
without access to clean water. It is possible to drill boreholes and set up manual
pumps in nearly all of these, and this can be done for less than 10.000 USD on
average. This equals 1 billion $, which sound like a big amount. But it can be
compares with the amount that the EU and US give to their farmers every day. So if
the farmers in these rich countries could do without the support for just one day, all
the villages of Africa could get access to clean drinking water!!
It is also equal to the amount of money Americans use in 3 days on visiting Mc
Donald or other Fast Food Shops.
Chinese floods
Water is killing people in other ways than by spreading diseases.
The last 25 years more than 300,000 people have been killed by floods world-wide.
Some years ago we saw how the Yangtze River flooded large parts of China and
killed thousands of people. The big part of the reason for these floods can be found in
human activities. China has had a very big economic growth during the last 20 years,
and much building activity has been carried out. The timber for these constructions
have come from the inner China, where large forest areas have been clear felled.
Even though new forest have been planted all the time, it has not been enough. When
there is less vegetation, there is more of the rainwater which runs to the rivers instead
of being stored in the ground and replenishing the groundwater. It was because of
these extra large volumes of water that the Yangtze river overflowed. The Chinese
government took a radical decision and banned all logging in the whole Yangtze
River Basin. At the same time enormous reforestation projects were started. China
now imports its timber from Siberia, where there is an huge amount, and where there
are no great problems of flooding.
Large dams or local solutions for water management
Until recently it was commonly thought that all the water problems could be solved
by building huge dams. At the same time these dams have given the possibility to
produce vast amounts of clean electricity, and today 1/5 of the world's electricity is
produced by hydropower stations.
It has since become clear to many that the large dams also create many problems.
One of the problems is that the lifetime of the dams is reduced all the time because
more and more soil is washed out with the rainwater. One of the largest dams in the
world - the Itaipu between Brazil and Paraguay - have thus seen this problem and are
paying big amounts of money to research and development of agricultural systems
which reduce the erosion. These minimum tillage systems are now used on over half
of the farmed area of Brazil. The soil is not ploughed, but the crop is planted directly
on the old crop residues, after they have been cut up into smaller pieces. When there
is such a layer of plant material on top of the soil there is less soil erosion. At the
same time the evaporation is reduced and the plants get better growth conditions.
One of the problems with big dams are that many people are moved from their land
to make space for the big lakes behind the dams. At least 40 million people have been
moved because of dam construction.
The question of electricity production could be solved in other ways - for example by
building smaller dams, or by using turbine systems which produce electricity without
stopping the water.
The main problem is whether the big dams actually are a solution which help many
people, and especially the many who need it most.
There has for example been large protests in India against the construction of the
Narmada Dam north of Bombay. Large canal systems have here been constructed to
bring water to the dry areas of Rajasthan and Gujarat. One problem is that much of
the water is lost on the way through evaporation and seeping out. Another problem is
that the big centralised systems give the possibility that the ones who have power
decide who can have the water - a common problem in India.
In some parts of Gujarat and Rajasthan people have shown that it is possible to
establish good water management systems where the rainwater is caught and stored
in traditional systems. These are a number of small and larger earthen ridges, which
stop the rainwater. With this system more of the water is used by the plants or seeps
into the ground and to the groundwater. In an area of Alwar District this simple
system has made 14 rivers run again after they had been dry for many years.
A local environmental group in the Bana River Basin has made the same experience
in Gujarat, and have been able to secure sufficient water for people, animals and
agriculture in three experimental areas by using the traditional systems combined
with new knowledge. They have developed a large scale plan for the whole river
basin and shown how it can be possible to produce electricity by establishing energy
forests instead of building large dams. It is possible to produce more electricity for a
much smaller amount than what they are using for the Armada Dam. There are many
other advantages of using such a model. First of all everybody is secured water for
themselves and their animals since the water is stored locally where people are. By
producing the power locally it is also creating many workplaces in the energy forests
and the local power plants where the energy is produced from the biomass.
These forests are also important in securing that a still larger part of the water ends in
the groundwater. When there is more forest and vegetation there is less erosion - and
less soil and nutrients are washed away with the rainwater. It is huge amounts of
nutrient which are washed away through erosion. Malawi, a country double the size
of Denmark, is for example every year loosing topsoil worth 100 million USD from
their farmed area. It has here been calculated what it would cost to buy the amounts
of fertiliser needed to replace the ones which are washed away.
The large amounts of soil being washed away at the same time creates big problems
in the countries where they end. They accumulate on the bottom of large rivers, and
gradually there is less place for the water in the river bed. When there is
extraordinary much rainfall this will create floods. This was exactly what happened in
Mozambique 2 and 3 years ago. The reason is the large areas which have been felled
in the neighbouring countries, and which are now cultivated in ways which give
much erosion.
There exists many systems to reduce this problem. There are the systems of minimum
tillage, where as much of the soil is kept covered with plants and plant residues.
It is possible to plant certain plants such as the vetiver grass in contour rows across
the slopes. This grass is very efficient in preventing soil erosion and preventing the
water in running off. Gradually terraces will be formed, which also makes it easier to
cultivate the slopes.
Many fast growing trees exist which are able to reduce soil erosion, and where people
at the same time benefit from the trees - either by edible fruits or leaves, oil from
seeds, as fencing against animals or as a supply of firewood.
The Rivers Indus and Ganges - minimum tillage systems save large amounts of water
Good systems have many places been developed to reduce the water problem. One of
the UN agricultural organisations has for example developed a systems which can
save huge amounts of irrigation water in Pakistan and India. In the river basins of
Indus and Ganges the normal system is to grow rice in the rainy season and after that
grow wheat. When the rice is harvested the field is ploughed many times to transform
the wet rice field into a dry wheat field. It is common to plough 6-8 times. A new
system has now been developed where wheat is planted directly in the rice field after
one passing with a specially constructed equipment which mulches the rice residues
and rips the field. The system is spreading rapidly because the farmers can save a lot
of money - because of fewer tractor hours, but also because of less need for irrigation
water, which is expensive in India and Pakistan. With the new systems they need less
irrigation because there is still humidity in the soil, and the plant cover reduces
evaporation. The farmers save 1 million litres of water for every ha ( the same as two
football fields).
Salt - destruction of farm land
More and more of the worlds agricultural land is destroyed by salt and already 1/8 of
all the irrigated farmland is more or less spoiled by salt. It is especially countries such
as Australia, India and Pakistan which are affected. The last two countries have built
huge canal systems, which leads water out for irrigation. Good draining systems were
not made, and the water was therefore not able to run off. As these countries are very
hot and have much sunshine, much of the water evaporates and leaves some salt.
Even though it is small amounts, the salt gradually accumulates and it is now so
much that large areas can no longer be used for agriculture.
In Australia it has been calculated that the salt problem costs about 350 million USD
every year because of reduced production and destruction of agriculture property.
Floods in Europe
Not only third world countries have problems with water. Last year there were
devastating floods in Germany, Poland and France. These were not only created
because it rained a lot over a short period. The problem comes because more and
more water is led directly to the rivers. The cities are spreading, road and train
systems grow, more soil is drained and the stream are straightened out. All of this
results in more rainwater running quickly to the rivers. Previously much of this water
was stored in the soil or in wetlands. So even though it rained heavily the volumes of
water were gradually released to the rivers. But today the rainwater run directly to the
rivers and causes floods when there are heavy rains.
Groundwater in Europe
Another water problem in the West is that more and more polluting chemicals end up
in the groundwater. This is for example pesticide residues. Earlier it was believed that
the groundwater was located so deep that the pesticides would not reach it before
they were broken down. But it has become a big problem, and it is now necessary to
use large amounts of money to clean the groundwater so that it can be used for
drinking water. England for example uses 100 million USD every year to clean the
groundwater of pesticides. In Germany some of the large water companies - for
example in München - are paying the farmers to transform their farms to ecological
farms. It is cheaper for the water companies to prevent more poisons coming into the
groundwater, than to be forced to clean it.
Conclusion
It is clear that the water problem is one of the serious problems the world faces.
Something radical has to be done. But it is also clear that many things can be done, if
there is an interest in solving the problem.
It is possible to introduce farming systems where the soil is not ploughed, so that less
water runs from the fields or evaporates, and less irrigation is needed.
Systems can be made where less of the valuable nutrients are washed away. At the
same time this will reduce the problem of floods where the materials end, and the
problem of shortening the lifetime of the large dams.
It is possible to drill boreholes and establish water supplies in all the villages which
are still lacking, for a fraction of the funds given as support for the farmers in the rich
world.
It is possible to create local systems which can secure water for people, animals and
fields, electricity by local production from energy forests without building huge dams
and having to move millions of people.