Radar Technologies International: Water Explorations in Darfur

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Amid the Darfur Crisis in 2004, more than 250,000 Sudanese refugees were forced to relocate to the desert landscape of eastern Chad. In a disaster situation, medical treatment and basic necessities become priorities for survival. Above all, the greatest need for survival was water. It is estimated by the United Nations High Commissioner for Refugees (UNHCR; 2008) that one person requires a minimum of 15 liters of water per day for basic survival. In the arid desert climate of eastern Chad, water is not readily available or easily accessible, leaving many refugees below the UNHCR standard for minimum daily water requirement (European Space Agency, 2013). 

AuthorsHolly Miller and Larisa Serbina

Every passing day without an adequate supply of water meant the loss of 200 children’s lives in the camps (Alain Gachet, Radar Technologies International, written commun., 2013) and water trucking cost the UNHCR millions of U.S. dollars per day. The need for water in refugee camps in the midst of a devastating human crisis was recognized as a major problem needing immediate attention.

In 2004, UNHCR requested that the United Nations Operational Satellite Applications Programme (UNOSAT) address the problem of water supply and help locate groundwater reserves to provide water for the refugees. With so many human lives at stake, the problem needed an immediate solution. UNOSAT reached out to Radar Technologies International (RTI), a French based company led by Dr. Alain Gachet (Radar Technologies International, written commun., 2013), to solve water supply issues. RTI, funded by USAID, partnered with USGS in designing a solution.

Due to the urgency of the matter, and the conflict in the area, the research team needed to use the most efficient technology available for the task. Landsat became an obvious choice, due to its relatively high spatial resolution, as a tool for landscape and terrain analysis. Twelve Landsat images were used in the identification of geological structures such as faults, dikes, and drainage channels, in combination with new Shuttle Radar Topography Mission (SRTM) data. This information was used with RTI’s WATEX System which combines geology, slopes, fractures, watershed boundaries, regional precipitation and temperature data. The WATEX System allowed RTI to produce groundwater target maps using Landsat imagery as a basic input. Between 2004 and 2005, 250,000 square kilometers (km2) were surveyed in the Darfur region. The maps identified where to drill and where not to drill in order to obtain water (fig. 1).In 2004, with the help of UNHCR, around 250,000 refugees in eastern Ouaddai in Chad were provided water from this project (fig. 2). In 2005 and 2006, with contributions from USGS and the U.S. Department of State, this project contributed to the survival of hundreds of thousands of people in the internally displaced persons camps in Darfur in Sudan (Alain Gachet, Radar Technologies International, written commun., 2013). The successful identification and drilling of 1,800 wells since 2005, with a drilling success rate of 98 percent, delivered water to the region. This work could not have been accomplished in the time frame needed without the existence of Landsat data. Landsat’s resolution and its variety of spectral bands aided greatly in the success of water exploration.

Maps based on Landsat images created by Radar Technologies International’s WATEX System to identify potential sites to drill for

Maps based on Landsat images created by Radar Technologies International’s WATEX System to identify potential sites to drill for water. Courtesy of Radar Technologies International.

In 2004, with the help of UNHCR, around 250,000 refugees in eastern Ouaddai in Chad were provided water from this project (fig. 2). In 2005 and 2006, with contributions from USGS and the U.S. Department of State, this project contributed to the survival of hundreds of thousands of people in the internally displaced persons camps in Darfur in Sudan (Alain Gachet, Radar Technologies International, written commun., 2013). The successful identification and drilling of 1,800 wells since 2005, with a drilling success rate of 98 percent, delivered water to the region. This work could not have been accomplished in the time frame needed without the existence of Landsat data. Landsat’s resolution and its variety of spectral bands aided greatly in the success of water exploration.

Successful water wells drilled in Eastern Ouaddai, Chad, located based on information provided by Landsat images processed in th

Successful water wells drilled in Eastern Ouaddai, Chad, located based on information provided by Landsat images processed in the WATEX model. Courtesy of Radar Technologies International.

Dr. Gachet, who has led water explorations in Chad, Sudan, Ethiopia, Angola and Northern Kenya, says the following: “Landsat, with [the] Shuttle Radar Topography Mission (SRTM), are both a prodigious U.S. gift to humanity. Landsat with 7 frequencies offers a broad chemical-lithological vision of the surface of the earth, with a pixel size of 30 m which is far enough for resolving the major geological issues” (Alain Gachet, Radar Technologies International, written commun., 2013).

Additionally, in 2010, Landsat together with WATEX has been used to survey 50,000 km2 in search of groundwater in Angola’s Kuenza sedimentary basin for reconstruction after the Angola Civil War. The old geologic data gathered by the Portuguese in the region had been destroyed during the Civil War. Landsat imagery became the only way to quickly acquire land and terrain maps.

In 2012 and 2013, Landsat and the WATEX System were also used to survey 36,000 km2 in Turkana County in Northern Kenya and 16,000 km2 in Northern Ogaden, Ethiopia. There has also been great interest from the new government of Kenya in a survey of all 590,000 km2 of the country. The Iraqi Government and European Union (EU) have expressed their need to cover all of Iraq (436,000 km2) with Landsat and the WATEX model, while USGS has expressed the will to cover the 400,000 km2 Ogaden region of Ethiopia.

These applications of Landsat help save thousands of lives in extreme conditions and contribute to future economic development through agriculture. They have helped with identifying new possible camps for refugees near water and helped bring water to already established villages. Landsat has allowed for short response times and accurate data. No other data source comparable to Landsat’s capabilities is currently available, making it a unique and valuable asset.

References: 

European Space Agency (ESA), Satellites guide aid workers sinking water wells for African refugees: European Space Agency, accessed on May 10, 2013 at http://www.esa.int/Our_Activities/Observing_the_Earth/Satellites_guide_aid_workers_sinking_water_wells_for_African_refugees.

Dr. Alain Gachet, Scientist/Engineer/Owner, Radar Technologies International, France.

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