Water Supply and Sanitation in Yemen - Water Resources

Water Resources

With renewable water resources of only 125 cubic meters per capita/year Yemen is one of the most water-scarce countries in the world. This level is less than one tenth of the threshold for water stress, which is defined at 1,700 cubic meters per capita/year. Total water demand of 3,400 million cubic metres per year exceeds renewable resources of 2,500 million cubic metres per year, thus leading to a steady decline in groundwater levels, varying between 1 m per year in the Tuban-Abyan area and 6–8 m per year in the Sana’a basin. Today, there are between 45,000 and 70,000 wells in Yemen, the majority of which are under private control. No one can be certain of the exact number, as almost all were drilled without license.

Agriculture takes the lion’s share of Yemen’s water resources, sucking up almost 90 percent, and it is estimated that qat production accounts for 37 percent of all water used in irrigation.

Sana'a example. Sana'a could be the first capital city in the world to run dry. Even today, many wells have to be drilled to depths of 2,600 to 3,900 feet (790 to 1,200 m), extremely deep by world standards. The combined output of the 125 wells operated by the state-owned Sana'a Local Corporation for Water Supply and Sanitation barely meets 35 percent of the growing city’s need. The rest is supplied either by small, privately owned networks or by hundreds of mobile tankers. In recent years, as water quality has deteriorated, privately owned kiosks that use reverse osmosis to purify poor-quality groundwater supplies have mushroomed in Sana'a and other towns. Future supply options include pumping desalinated water from the Red Sea over a distance of 155 miles (249 km), over 9,000-foot (2,700 m) mountains into the capital, itself located at an altitude of 7,226 feet (2,202 m). The enormous pumping cost would push the price of water up to $10 per cubic meter.

The minister for water and the environment, Dr Abdulrahman al-Eryani, is an agricultural engineer - and he said: “The Sana’a basin is using water 10 times faster than Nature is replenishing it,” he told me. “And before long there won’t even be enough to drink. I am not an optimist. I think many of the city’s people will simply have to move away. “The solution I am proposing is a very clear policy - a voluntary one - of reallocating people from here down to the Red Sea coast. We could use renewable energy there to desalinate sea water. And it would be cheaper than trying to provide enough water to Sana’a. “This is not the first time that Yemenis have had to move to avoid disaster. It’s happened many times in the last few thousand years, when Nature allowed the population to increase rapidly. This time, though, there are political frontiers in the way of an exodus.”

“Along the coast between Al Mukallā and Aden a number of fishing villages are supplied by water within a half mile of the shore. The water levels are a few feet above mean sea level and probably represent wedges of freshwater floating on sea water (Ghyben-Herzberg Principle). The fresh water has probably originated from the higher ground behind the coastal plains by slow seaward movement, and partly from natural precipitation.”

Groundwater near the city of Ibb is polluted by leachate from a landfill is a source of pollution.