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Sunday, April 12, 2015

Climate Change: Averting groundwater depletion walk by 2030

A call for better understanding of groundwater resources is imperative for development of groundwater industry, reports REMMY NWEKE. Excerpts.

UNESCO DG, Irina Bokova:
As the Food and Agriculture Organisation (FAO), United Nations Education, Scientific and Cultural Organisation (UNESCO) alongside the World Bank, Global Environment Facility (GEF) and International Association of Hydrogeologists joint meeting kicks off this week under the aegis of 7th World Water Forum in Daegu and Gyeongbuk one thing that has reverberated lately is the need to ensure globally that actions on irreversible ground water depletion is averted.

A United States-based hydrologist with Geological Survey in Sacramento, California, Steven Phillips, had defined groundwater as “… any water that lies in aquifers beneath the land surface.” 

Although experts at the National Centre for Groundwater Research and Training (NCGRT) with headquarters at Flinders University, Adelaide, Australia, also defined groundwater as water that is located below the earth's surface. 

Ultimately, water from rain and rivers migrates through the ground and is stored in porous soils and rocks. The study of groundwater is known as hydrogeology, while issues pertaining to groundwater could affect the challenges or otherwise of climate change, depending however, on how its managed and taken seriously.

Groundwater most poorly understood aquifers:
NCGRT experts informed NaijaAgroNet that groundwater is found in vast quantities filling the spaces between grains of soil or rock; it slowly flows through aquifers; connects with rivers, streams, lakes and wetlands; feed trees and vegetation. 

They cited Australia as a very old continent, and much of its groundwater is tens of thousands, even hundreds of thousands of years old. For example, the Great Artesian Basin in central Australia is the largest aquifer of its kind in the world, covering 22 per cent of Australia, and containing water that is more than a million years old.

Groundwater, NCGRT experts said, makes up 98 per cent of the fresh water on the planet. It currently makes up around a third of our total water consumption, although this varies from location to location. In the Northern Territory, 90 per cent of water is sourced from aquifers, while the highest concentration of groundwater use is in the Murray–Darling Basin. 

FAO's Moujahed Achouri:
Experts went onto to inform NaijaAgroNet that in spite of its importance, groundwater is poorly understood and often undervalued. This may in part derive from the nature of groundwater: a complex, hidden resource that is difficult to conceptualise. 

The area where water fills the aquifer is called the saturated zone (or saturation zone). The top of this zone is called the water table. The water table may be located only a foot below the ground’s surface or it can sit hundreds of feet down.

Global community must work against depletion:
NaijaAgroNet recalls that as prelude to the meeting, calls have come from the aforementioned organisation for action by the global community to manage the increasingly urgent depletion and degradation of limited groundwater resources.

They also proposed a set of principles governments could use for better groundwater management, including the 2030 Vision and Global Framework for Action which represents a bold step for collectively responsible action among governments and the global community to guarantee sustainable use of groundwater.

NaijaAgroNet gathered that for too long, groundwater governance has remained an area of policy neglect, resulting in its degradation and depletion. Just as global groundwater abstraction reportedly tripled over the past 50 years, as experts claimed that over a fourth of current withdrawal is non-sustainable and spread groundwater pollution has threatened humans and the environment.

Most urban aquifers, experts argued, have suffered from sanitation issues while coastal aquifers are exposed to saline water intrusion, even as industrial pollution, pesticides and fertilizers also find their ways into reservoirs.

The amount of renewable groundwater, therefore, NCGRT experts led by its director, Professor Craig Simmons stated, is unevenly distributed across regions. Some areas, especially those with low rainfall, are at risk more than others. Withdrawal intensity is highest in large parts of China, India, Pakistan, Bangladesh, Iran, the US, Mexico and Europe. This could result in lost freshwater reserves at a time when groundwater storage is critical for sustaining water security and adapting to climate variability.

Building industry around groundwater:
To build an industry around groundwater will amount to near perfect understanding of groundwater and obviously understanding its importance, hence there is need to define an aquifer, which is an underground geological formation which transmits and contains appreciable quantities of groundwater. 

Water in the ground travels, experts say, flow slowly through pores or fractures, depending on the type of sediment or rock material the aquifer is made of. 

Aquifers could vary prominently in the quality and quantity of water they hold and the extent of their connectivity with other aquifers or surface water bodies. 

Equally essential is to know there are two main types of aquifers, according to experts, namely the ‘unconfined’ and ‘confined'

Unconfined aquifers:
And unconfined aquifers are characterised by the absence of a low-permeability thereby confining a layer above them. Their watertables are typically close to the surface and roughly follow the changes in the land surface.

These aquifers are an important source of groundwater in Australia, for instance, because of their relative shallowness and hence ease of access. Just as in low-lying areas, groundwater from these aquifers is often released as natural springs, streams and wetlands. 

Confined aquifers:
GEF's Naoko Ishii:
Confined aquifers, thus are permeable rock units deep under the ground and overlain by less permeable layers. Replenishment occurs in areas known as recharge zones where the aquifer is unconfined and which may be a long distance from the confined portion of the aquifer. 

Experts at NCGRT explained that pressure from the recharge zones creates high water pressure in the aquifer beneath the confining layer. Sometimes the pressure is so great that, where there is a break in the confining layer, water will naturally rise and bubble to the surface without the need of a pump. This is called artesian flow. 

They said, watertable in a confined aquifer is called the piezometric surface and does not necessarily follow the land surface.

In response to the essence of groundwater, a Senior Director, World Bank Group Water Global Practice, Mr. Junaid Ahmad, noted that since time immemorial humans have sought water from the soil, “But we have moved from a village being based around a well to whole cities and industries being built around groundwater. 

“We have learned how to dig ever deeper, pump ever harder, and how to turn deserts into breadbaskets. But we have done this without considering the rate at which our groundwater is recharged, and so we should not be surprised when our wells run dry. Much as we have invested in pumps and crops, so now we must invest in groundwater governance," Ahmad said.

GEF wants urgent action on groundwater:
The chief executive officer and Chairperson, Global Environment Facility (GEF) Naoko Ishii, noted that her team and world at large, could no longer take this invisible but vital source for granted, hence urgent action is needed to ensure its long term availability.

“We look forward to joining hands with partner agencies and countries to ensure water for drinking, food, cities, energy and industrial uses is available for generations to come,” she said, declaring “Sustainable management of groundwater is key to maintaining ecosystems and adapting to climate change.” 

NaijaAgroNet reports that in response to the urgency of the situation, a product of four years of consultations with stakeholders from over 100 countries; these principles focus on legal and institutional frameworks, policies, and plans as well as information and incentive structures for sound and effective groundwater management.

No doubt, this process signals strengthened collaboration across the international community to understand the barriers to better groundwater governance and address key regional challenges.
Moujahed Achouri, Director, Land and Water Division at the Food and Agriculture Organization (FAO) intimated NaijaAgroNet that collective and coordinated action is urgently needed to protect and prolong the integrity of aquifers. 

He stressed the cost of inaction could be enormous, because this vision and framework are urgent calls to decision-makers to act now with the right political decisions to help reach globally shared goals of social and economic development”.

For the UNESCO Director-General, Irina Bokova, to make groundwater governance a reality, it is necessary to foster cooperation among countries, especially on transboundary aquifers. Pointing out that “Water directly influences our future, we must work together to manage this precious resource more sustainably."

In summary, groundwater is indispensable to poverty reduction and shared prosperity, mostly looking at its accounts for over a third of municipal and industrial supply and some 40 per cent of the global irrigated area is serviced by groundwater. 

According to experts, groundwater has the potential to provide an improved source of drinking water for millions of urban and rural poor people. Yet, many poor farmers and their families depend on it to irrigate their crops and sustain their livelihoods.

The 2030 Vision and Framework for Action which provides the enabling framework and guiding principles for a coordinated action among governments and organizations should be upheld in order to achieve the goals of this vision for a definite better water and groundwater management as part of the efforts at combating climate change.

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Pix: UNESCO D-G, Irina Bokova; Chairperson, GEF, Naoko Ishii, & Moujahed Achouri, Director, Land and Water Division, FAO.

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