Hitting The Ground Flowing: Ways to Sustainably Manage Groundwater Supply and Demand
Groundwater conservation is a key part of managing water resources. A renewed focus is needed on the protection of this valuable resource.
The global demand for water is projected to grow by 55% by 2050 according to the Organisation for Economic Co-operation and Development. This sharp increase is disproportionately driven by regions that experience high rates of urbanization and economic growth, many of which can be already classified as water scarce today.
Regions that have lived beyond their naturally available water resources for too long often show telling signs of resource overuse. These include land subsidence, cone depressions, sinkholes or saltwater intrusion, next to disappearing aquatic, riparian and even terrestrial ecosystems. The environment, the economy and ultimately people bear the brunt of the negative consequences.
Often, this is because the underground aquifers have been depleted over the years. It is groundwater resources that have shouldered some of the world’s greatest agricultural and socio-economic success stories, including India’s breadbasket, nourishing half a billion; California’s agricultural belt, producing some of the world’s highest value crops; or Jakarta’s continuous growth, quenching the thirst of millions.
Many aquifers contain fossil water, meaning they are at times millions of years old and do not recharge. Once the water is used up, the aquifer remains dry forever, as was the case in Saudi Arabia, which fueled one of the world’s largest wheat productions with fossil groundwater during the early 2000s.
However, even when aquifers naturally recharge, many are depleted at an unsustainable rate. For example, water from some of the main aquifers in the northern People’s Republic of China, India or the Middle East is extracted at 5-20 times the sustainable rate.
The increasing depletion of groundwater is a consequence of insufficient management of this invisible but valuable resource. In many developing countries, groundwater is considered free-for-all, unlimited access for everyone without having to request for permissions. As a result, groundwater is being pumped at far greater rates than it can be naturally replenished.
Many aquifers contain fossil water, meaning they are at times millions of years old and do not recharge.
Climate change further exacerbates the shortage of groundwater by reducing rainfall recharges substantially. The prolonged droughts in many countries have led to increased pumping of groundwater as the natural response of humans to climate disasters.
Suffering the impacts of groundwater overdrafts, many governments have attempted to encourage more sustainable management practices to recharge, protect and conserve their groundwater resources.
This includes replenishing the groundwater supply, for example through managed aquifer recharge, but also reducing pressure on surface water resources through supporting the development of alternative sources, such as rainwater, smarter water allocations, and more efficient irrigation techniques.
In countries where water rights are clearly defined such as Australia, Spain, or the United States, restrictions to groundwater extraction have been imposed, and water markets have been increasingly established to promote more efficient use of water.
Another adaptation strategy, recharging aquifers, is still a relatively new concept but has been proven a viable technology in many places. The city of Beijing has successfully replenished its aquifers for several years now, thereby effectively responding to fluctuations in surface water supply and municipal and industrial demand, next to restoring wetlands that can act as a natural buffer during flood events while also offering the dual benefits of open green spaces for the public.
Making groundwater distribution and use more efficient often requires substantial investments in infrastructure, such as building new canals, lining irrigation channels, or installing drip irrigation systems, as well as advanced monitoring tools, e.g., remote sensing. In addition, investment in policy reforms that clearly define rights for groundwater access is essential for an effective management and monitoring of the resource.
If regions can manage both groundwater supply and demand more sustainably, distribution costs can be reduced, their water supply systems gain improved flexibility and resilience irrespective of drought or floods, while supporting the restoration and rejuvenation of fragile ecosystems.
A groundwater protection project in Shandong Province in the People’s Republic of China achieved several of the benefits mentioned above and led to tangible social, economic, and environmental outcomes, including improving flood control and drought relief through greater water storage capacity (for both drinking and flood management) as well as rehabilitating 887 hectares of important wetland areas.
The project was successful because it combined expertise in adoption of innovative technology through piloting smart greenhouses and groundwater use monitoring systems together with long-term planning across financial, environmental and regulatory dimensions.
A critical element of such successful interventions is ongoing capacity development and training of staff from the Shandong Provincial Government and local governments on project management procedures, technical design and implementation, and safeguard supervision and monitoring.
Groundwater conservation is a key part of managing water resources and World Water Day provides a renewed focus for the importance of protecting this valuable resource.