Over-abstraction of groundwater

 

Photo credit: CGIAR

 A well in Tunisia.

Groundwater over-abstraction in the MENA region: 5 problems and some solutions

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In the Haouaria Plain of Northern Tunisia, a too familiar scene unfolds: a farmer stands near the edge of a wide hand-dug well, distraught. Groundwater levels continue to drop every year, increasing salinity and reducing the amount of crops that can be cultivated. Precipitation does not replenish the shallow aquifer like it used to. Groundwater depletion is a vexing phenomenon threatening sustainable economic and social development in the Middle East and North Africa (MENA). Controlling and managing over-abstraction has become a clear challenge for policy-makers, managers and academics in the region.

Can innovative policies and regulations be used to reverse the current trend of groundwater depletion? This complex problem requires a systematic far-reaching approach that builds on existing knowledge and practices within and beyond the region. Implemented by IWMI and national partners in Tunisia, Lebanon, Jordan, and the UAE, a three-year USAID-funded project studied the uses, limitations and potential of policy tools and stakeholder dialogue to curb groundwater over-abstraction. The project has found that the current regulation and management tools in the MENA region suffer from five “wicked” problems that prevent them from properly addressing groundwater issues.

1. Scattered web of groundwater users

The main problem affecting groundwater resources in the MENA region is the myriad and scattered number of groundwater users.

Read the full article: CGIAR

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Groundwater irrigation efficiency and soil fertility in drylands

 

 

The water under your feet in Laos

The water beneath our feet is a valuable irrigation resource for farmers affected by drought in rural Laos, and can increase crop yields and income for farmers. Students at the Faculty of Water Resources and Management have created an experimental site to research groundwater irrigation efficiency and improve soil fertility. They found that the best way to save water is by using drip irrigation, and that the more crops were produced when compost was added to the soil.

 

Solar pumps in Ethiopia

Photo credit: Africa Rising – https://agintensificationafrica.files.wordpress.com/2015/10/solar-pumps.jpg?w=225&h=300

 

Solar pumps seeing the light in Lemo, Ethiopia

In September 2015, the International Water Management Institute (IWMI) installed solar pumps in Upper Gana and Jawe, two communities in southern Ethiopia.

The new solar pumps developed by the Dutch NGO Practica and produced in Kenya are for the first time being implemented in Ethiopia. Africa RISING is the first to test them out – or rather the farmers are the first.

Together with IWMI, farmers cultivating avocado, fodder and vegetables will be testing the robustness of the technology in the upcoming dry season. Aside from the agronomic and irrigation research, IWMI will be working with the Omo Micro Finance Institution to assess whether it is a viable investment.

Read the full article: Africa Rising

 

New project will reduce floods and boost irrigation

Photo credit: Google

Women worshiping in holy Ganga river during Sattuani festival in Patna on Tuesday.

 

Ganga floodwater to be stored underground

(30 Oct, 2015 – Uttar Pradesh, India) A new initiative launched today in Uttar Pradesh could revolutionize flood management while at the same time boost groundwater stocks for dry season irrigation. Located in Jiwai Jadid village, 20 kilometers east of Rampur town, the project will be the first ever to adopt the new approach which is being developed by scientists at the International Water Management Institute (IWMI).

The initiative, called Underground Taming of Floods for irrigation (UTFI), channels surplus surface water from flood‐prone rivers or their distributary canals during the wet season when there is a high flood risk to a modified village pond. Brick structures in the pond allow the water to flow swiftly down below ground, where they infiltrate the local aquifer. This water can then be pumped back up again during the dry season so that farmers can maintain or intensify their crop production.

“This is an exciting concept which has never really been done before and whose benefits go directly to local and wider communities,” said Paul Pavelic, of the International Water Management Institute (IWMI), who leads the research. “Putting this into practice will save on the large funds spent each year on relief and restoration efforts of flood victims and on subsidies for groundwater extraction during the non‐rainy season. We hope our approach would tackle the root causes of the problem rather than the consequences. ”

The Ganga basin suffers from regular floods with the mighty Ganga and its tributaries like Ramganga, Yamuna, Mahananda, Koshi all flooding almost annually. During the rainy season, large volumes of   excess water run off the Himalayan range often causing great damage downstream. On the other hand, some of the same regions face a shortage of water aggravated by year ‐ round agriculture production which is largely dependent on groundwater pumping particularly in dry season when canal water is limited. To deal with this variability, IWMI’s experts have devised a way to selectively capture excess water flows during monsoons and store this in aquifers underground.

The size of the land around the pilot that would receive direct benefit is currently under investigation. With floods being a common occurrence across the Ganga basin, researchers hope that the scaling up of this intervention would help in effectively protecting lives and assets downstream, boosting agricultural productivity and improving resilience to climate shocks at the river basin scale. This will be especially important to help communities deal with climate change which is likely to bring ever more variability in water supply and rainfall.

Read the full Press Release: IWMI

Drought in California

Photo credit: Nature World News

Aqueducts in California, one of which is pictured here, are being pumped to combat the state’s current drought. The amount being pumped is causing an increased rate of subsidence in surrounding areas. (Photo : Wikimedia Commons )

Drought Conditions in California are Causing Severe Subsidence

By Samantha Mathewson

As California continues pumping groundwater to combat the historic drought they are facing, land in the San Joaquin Valley is sinking at an increased rate of 2 inches more per month. The California Department of Water Resources released a NASA report illustrating their findings.

“Because of increased pumping, groundwater levels are reaching record lows — up to 100 feet (30 meters) lower than previous records,” Department of Water Resources Director Mark Cowin said in a statement. “As extensive groundwater pumping continues, the land is sinking more rapidly and this puts nearby infrastructure at greater risk of costly damage.”

NASA compared satellite images taken of Earth’s surface over time to discover this increased rate of subsidence.Interferometric synthetic aperture radar (InSAR) observations from satellite and aircraft platforms have been used over the past few years to produce maps of subsidence with approximately centimeter-level accuracy. Using multiple scenes, researchers at NASA’s Jet Propulsion Laboratory (JPL) were able to produce time histories and profiles of subsidence at selected locations to show the variation over time.

Read the full article: Nature World News

Tamil Nadu (India): water woes

 

Desertification of Tamil Nadu: Private Wells & Paddy

To understand the scale of Tamil Nadu’s water woes, let’s understand what the demand is and how much water there is to divvy up. The demand estimate by the various sectors are,

demandssplit

 

This 1,894 TMC is well beyond total assessed water resources in the state which is 1,587 TMC. In other words, the demand is 19.3% over and above known supply. So even if there’s good/normal rainfall in Tamil Nadu, the demand exceeds supply. Partly because we discharge fresh water into the sea in some cases and because we haven’t invested enough in processes to recharge aquifers. But even if all of that is done, it’s unlikely this deficit will vanish.

With agriculture/irrigation taking up 93% of the demand, that becomes the only segment that demands our attention. Sure the City of Chennai and its bourgeoisie waste a lot of water or appear to when measured on per capita consumption of domestic water compared to their rural counterparts. But that’s inconsequential in the overall scheme of things. Water scarcity in Chennai does not cause desertification. While Tamil Nadu’s unsustainable sectoral allocation will.

To understand where this 93% water largely gets used, let’s look at Tamil Nadu’s land use pattern. Tamil Nadu’s land area that is sown is 38.3% of its total surface area. That to those of us who aren’t familiar with the data, sounds like a staggeringly high number. Let’s understand where these farmlands are, and to what extent.

Read the full article: PURAM

Underground ocean

Photo credit: IBT

Workers digging a well for underground water are dwarfed by the sand dunes of the Taklimakan Desert, 13 September 2003, outside of Tazhong, in China’s northwest Xinjiang province.(FREDERIC J. BROWN/AFP/Getty Images)

Vast hidden ‘ocean’ found under Chinese desert

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Chinese scientists have discovered what could be a huge hidden ocean underneath one of the driest places on earth, the South China Morning Post reported on 30 July.

The Tarim basin in northwestern Xinjiang, China, is one of the driest places on Earth, but the vast amount of salt water concealed underneath could equal 10 times the water found in all five of theGreat Lakes in the US.

“This is a terrifying amount of water,” said professor Li Yan, who led the study at the Chinese Academy of Sciences’ Xinjiang Institute of Ecology and Geography in Urumqi, the Xinjiang capital.

“Never before have people dared to imagine so much water under the sand. Our definition of desert may have to change,” he told the South China Morning Post.

Scientists had long suspected that a vast amount of melt water from nearby mountains had slipped beneath the basin, but the exact amount of water remained unknown.

Accidental discovery

Li’s team made the discovery by accident. They had actually been looking for carbon dioxide, which is absorbed in certain areas – such as forests and oceans – called “carbon sinks.”

Scientists study carbon sinks to gain a greater understanding of climate change.

Around 10 years ago, the team discovered that carbon dioxide had been disappearing into the basin for 10 years, but could not understand why.

Read the full article: IBTimes