Aquifers can be valued, harnessed and protected says new study

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The World Bank sets out how and why governments must prioritise groundwater protection as a humanitarian and economic imperative.

In a new report examining the extent to which groundwater is depleting and the impact of this on economics and human wellbeing, the World Bank has stressed that across farming and domestic use, the picture is now very troubling.

The importance of groundwater

Groundwater provides 49% of the water withdrawn for domestic use by the global population and around 43% of all water withdrawn for irrigation. But despite this, the report, The economics of groundwater in times of change, warns that there has been a lack of systematic analysis of its economic importance, which in turn has seen it misused.

Offering new evidence that advances the understanding of groundwater’s value, the report makes the case for groundwater as a major asset in a country’s resource portfolio, representing both serious costs that result from mismanagement as well as great opportunities to leverage its potential.

To support that, a global aquifer typology has been developed and validated. It considers key aquifer characteristics that matter for resilient development and poverty reduction – determining the economic accessibility of the groundwater resource to individual farmers, its sustainability and buffering capacity of the aquifer to seasonal variations and climate shocks.

A valuable buffer and resource

The report highlights the value of groundwater as buffer able to reduce by a third the losses in economic growth caused by droughts. This is especially important for agriculture, where groundwater can reduce up to half of the losses in agricultural productivity caused by rainfall variability.

At the same time, in Sub-Saharan Africa in particular, untapped groundwater irrigation has the potential to significantly improve food security and poverty reduction. That results from analysis suggesting that although little land is irrigated in the region, local shallow aquifers represent over 60% of the groundwater resource, with an estimated 255 million people in poverty living above them.

Over-exploitation is costing economies dear

The report also suggests, however, that groundwater over-exploitation in some places exposes economies to exponential risks—including maladaptation. Globally, major alluvial aquifers account for more than 60% of groundwater depletion embedded in international trade. This includes regions with transboundary aquifers, adding further complexity and urgency to their management.

In the Middle East and South Asia, up to 92% of transboundary aquifers show signs of groundwater depletion. The effects of this depletion are already painfully felt in South Asia, where groundwater once provided an agricultural revenue advantage of up to 20% – an advantage now disappearing in areas affected by depletion.

In Sub-Saharan Africa, where groundwater has been underused given its potential, expanding solar pumping without adequate safeguards could threaten rural livelihoods, though much could be done to draw upon this resource sustainably. At the same time, degrading quality of groundwater aquifers is a challenge where urban expansion and unregulated agricultural practices have taken their toll.

Solutions that maximise value while sustaining this resource

The World Bank report makes a number of recommendations for countries to maximise the value they derive from groundwater without depleting that resources unsustainably. These recommendations include:

  • Aligning private and social opportunity costs by deploying policies that enable and support investment and drilling while placing a cost on negative externalities.
  • Deploy solar pumps rather than diesel pumps, to benefit from lower operating costs and thus bridge the access gap that sees many low-use rural areas unable to benefit.
  • Reform agricultural subsidies to address depletion-incentivising producer support subsidies, such as minimum support prices and government procurement contracts that push up production of water-intensive crops.
  • Supplement existing aquifer recharge infrastructure with better land management to limit rainwater run-off and increase soil retention capacity to better harness natural aquifer replenishment.
  • Engage better information and experience to ensure the best actions are taken for localised circumstances – avoiding a trial and error approach that has been seen before.

Click here to download the The economics of groundwater in times of change report.