Frances Marie
Water
and Sanitation (WASH)
Climate Change Adaptation
RAWDP to understudy and expand the Magnetic Resonance Sounding (MRS) in Chad
Geologists
in Chad are using Magnetic Resonance Sounding (MRS) to take
"x-rays" of the ground to find new water sources in eastern Chad,
where more than 300,000 refugees from neighbouring countries have arrived in
recent years. RAWDP has indicated a willingness to partner with the promoters
of the technology, the France-based IRIS Instruments. IRIS manufactures the
equipment and has trained experts to use
this technology to find water in Chad. RAWDP intends to deploy this technology
in parts of Chad where it is seeking perennial ground water supplies for
households. Methods used to search for
groundwater typically look at how rocks react to radar and electrical currents. These methods could lead to false readings of
the presence of water. The magnetic resonance
sounding is direct prospecting. "Here, a sign of water means there is
water, which means less unnecessary drilling," said Pierre Michel Vincent,
a hydrologist who recently worked with the Ministry of Water and the UN Refugee
Agency (UNHCR) in Chad. "Only one
out of three boreholes drilled in Chad produces water." Magnetic resonance
sounding sends electrical currents through the earth in search of hydrogen
atoms, giving a reading of how much
water the rocks hold. "This technique identifies where water is more
quickly than traditional geophysical studies."
Refugees
who have fled Sudan and Central
African Republic constitute 35 percent of eastern Chad's estimated 700,000
population, according to the most recent census. Hydrologist Vincent said there
is not enough information on half of the
4,000 recorded water points in the area to know if they are still producing
water. We could drill 500 more wells now
and still not have enough water. People
from local communities, as well as refugees, struggle to find even half of the 15 to 20 litres of water
per day recommended for drinking, cooking and bathing. Many were only able to secure six litres a
day on average, said UNHCR. "There
is not enough water to provide for the expanded population - we could drill 500
more wells now and still not have enough water." Erratic and insufficient
rainfall in 2009 resulted in Chad producing 34 percent less food than it did in
2008. This has wiped out livestock and
placed two million at risk of hunger in the country, the government noted. The eastern town of Iriba, which hosts 55,000
refugees, received 135mm of rainfall in 2009.
In 1950, it received three times as much, according to state records.
Equipment
manufacturers advise that an entire
sounding kit weighs around 350kg, requires training, and costs US$180,000. In
the past five years, groups in Mauritania, Algeria, Morocco, Rwanda, Niger, Burkina Faso,
South Africa, Mozambique
and Namibia have purchased magnetic resonance
sounding equipment. Its drawbacks are
that it can only read 150 metres into the ground, and readings are sensitive to
electromagnetic signals and power lines, making readings in cities difficult, Bertrand
said. After training in Goz Beida last October, IRIS Instrument and aid workers
identified a promising location for water right
outside the city, located 200km south of the eastern town Abéché. Oxfam Intermonde, a global relief NGO, is
studying drilling prospects. Bernard
said sounding complemented current groundwater search techniques, and might not
be right for all situations. "If you can cure an illness with an aspirin,
then there is no need to order the x-ray. But with worsening water shortages, different
techniques need to be considered. The
challenge and goal of groundwater exploration is to use the least amount of
money to find as much water as possible."