Drought, food supply fears boost small-scale irrigation - study

LONDON, Aug 24 (Reuters) - Farmers in South Asia and sub-Saharan Africa are increasingly taking up small-scale irrigation schemes as drought threatens the security of food supplies, a report by the International Water Management Institute (IWMI) said.

"With food security back on the international agricultural agenda, and climate change increasing the uncertainty of rainfall, it is an opportune time to reconsider investments related to irrigated agriculture," the study said on Friday.

Small-scale irrigation technology, such as motorized pumps and hosing to access groundwater, could cost a sub-Saharan African smallholder $250 or more but could improve crop yields by between 75 and 275 percent, the report said.

"Factors are working to potentially move the world into another food crisis like 2007-2008, triggered by a U.S. drought and the late onset and irregularity of the South Asian monsoon," Colin Chartres, IWMI director general, said in an interview.

"If there is more investment in small-scale irrigation, it means food supply in those countries is more secure. It won't replace the need for staple cereal crops, but it gives farmers more insurance against a food crisis."

Small-scale irrigation schemes usually cover areas less than 2 hectares. Farmers largely initiate and finance irrigation equipment individually or in small groups and use low-cost technologies such as buckets, watering cans and pumps.

In Ghana, around 185,000 hectares are under small-scale irrigation schemes, benefiting half a million smallholders, and some 170,000 farmers in Burkina Faso water vegetable crops in the dry season using small-scale irrigation, the IWMI estimates.

Vegetable production has nearly tripled in the Burkina Faso to 160,000 tonnes in 2005 from 60,000 tonnes in 1996 and is still growing, the report said.

FOOD, WATER TOP THE AGENDA

Food and water security are high on the world's agenda as the United States experiences its driest summer since the 1930s, sending grain prices to all-time highs and raising the spectre of a food crisis such as in 2008.

Climate change is also increasing the uncertainty of rainfall, meaning that groundwater supplies are not being replenished and rainwater is difficult to collect to feed crops.

The majority of the world's poor live in South Asia and sub-Saharan Africa and most of these people live in rural areas and work in agriculture. More

 

Saudi Arabia & Iran Are Overexploiting Their Groundwater Supplies

In the Middle East, water shortages are a widely accepted reality which many countries are trying to fight head on. Worldwide, however, the issue is not so pressing with environmental issues such as energy and emissions taking centre stage. Despite this, new research from McGill University in Montreal and Utrecht University in the Netherlands indicates that the world is increasingly dependent on an unsustainable supply of groundwater. They estimate that the world’s ‘water footprint’, which is defined as the area above ground required to sustain groundwater use, is about 3.5 times the actual area of the available aquifers. And this has huge implications not only on water supplies but for food and political security too.

Combining data from around the world, the research team has been able to measure the amount of water available and the water usage. The result which Tom Gleeson from McGill called ‘sobering’ indicate global overexploitation of groundwater in a number of regions across Asia and North America. The study suggests that around 1.7 billion people – mostly in Asia – are living in areas where underground water reserves are under threat. That means that we humans as well as the vast ecosystems that water supports, are blindly walking into crisis.

The areas that the research showed were under most stress include Saudi Arabia, Iran, northern India and parts of northern China. In the US, the areas included western Mexico, the High Plains and California’s Central Valley. The overexploitation of groundwater supplies in countries such as China, the US and India is linked to their global scale production of food.

“The relatively few aquifers that are being heavily exploited are unfortunately critical to agriculture in a number of different countries,” Tom Gleeson told Reuters. “So even though the number is relatively small, these are critical resources that need better management.”

The study found that Saudi Arabia had substantially depleted its own aquifers (as has Iran), which is why the country is buying up land in Africa to help ensure food security. However, it is not all bad news. According to the data gathered, groundwater depletion isn’t a worldwide problem and 80 percent of aquifers around the world aren’t being depleted. For example, some of the largest reserves of groundwater are under North African countries like Libya, Algeria, Egypt and Sudan and these haven’t been over-exploited yet.

The biggest scheme to get to this water was Libya’s $25 billion Great Manmade River project, built by the dictator Muammar Gaddafi to supply cities including Tripoli, Benghazi and Sirte with an estimated 6.5 million cubic meters of water a day. The problem is that once this water is taken out of these aquifers, it is not replenished and so the need to control our consumption of water is still a pressing issue.

Authors of the study suggest that limits on water extraction, more efficient irrigation and the promotion of diets with less meat (or no meat at all) could make water resources more sustainable. More