Rachael McDonnell provides water expertise at Abu Dhabi’s Crown Prince Court

Dr Rachael McDonnell was an invited speaker at a workshop on ‘Policy options for food insecure countries’ held in Abu Dhabi on 19-20 November 2012. The event was hosted by the Crown Prince Court and organised by the policy think tank Chatham House.

McDonnell’s paper contributed to important discussions on the role of innovations in science/technology and policy for improving water management in food production systems. She examined the contribution of marginal waters, saline and treated wastewaters, and discussed how these can be better leveraged to relieve the pressure on freshwater resources.

The United Arab Emirates (UAE) is a hotspot for food vulnerability. Rapid increases in water demand and population growth are compounded by extreme weather events and droughts leading to volatile food commodity markets.

The meeting brought together regional and international experts to discuss issues related to food security, including resource scarcities, crop breeding science, water efficiency strategies, environmental change and implications for policy. Other speakers included representatives from the United Nations Development Programme, the United Nations Economic and Social Commission, and the International Food Policy Research Institute.

Rachael McDonnell is a Senior Research Scientist at Oxford’s School of Geography and the Environment, and a Scientist (Water Policy and Governance) at the International Center for Biosaline Agriculture.


Africa Water Stewardship Scholarship quenches thirst for knowledge

Cliff Nyaga is a beneficiary of The Coca-Cola Company funded Africa Water Stewardship Scholarship, which funds his place on the MSc in Water Science, Policy and Management, class of 2012/2013. He reports on his first term studying at Oxford University’s School of Geography and the Environment.

12 December 2012, by Cliff M. Nyaga

As the first Africa Water Stewardship Scholar, I arrived in late September, tired but excited for the year ahead studying at Oxford University. The characteristic cold and grey British weather was a bit of a shock but was compensated for by the timeless elegance of the university colleges. Everything seemed quieter and more orderly than where I come from back home in Nairobi, Kenya.

The course started with meeting the 26 other students from 16 different countries on a fascinating residential field trip to Dorset and the Jurassic Coast. We got to know each other and the teaching staff over the weekend while studying various aspects of catchment management and the chalk aquifer system. The staff took us to a local pub where I got my first taste of English beer. Chat over a beer with my teacher? A first, but not bad experience!

Term started gently but then soon accelerated with intense academic activity, centred around taught modules on global water issues including water security, health and policy. There was much for me to work on, learn about, questions to ask and discussions to have. I was left wishing I had much more time. Field study trips in addition to rich study and research resources exposed me to new approaches to understanding and managing water issues and have also made me a better thinker. One highlight was visiting a green wastewater treatment plant at Wessex, where virtually ‘nothing is wasted’.

Not a week goes by in which I don’t attend a lecture from a visiting dignitary, or participate in debates and seminars that involve professionals working in the water sector. And when it’s time for a break from study, it’s easy to take a relaxing park stroll or hop on the bus and visit villages near Oxford (my favourite has been Burford, a village made of stone). A boat ride down the Thames in London was an unforgettable experience.

A great aspect of the scholarship is that I have been able to interact with key people at The Coca-Cola Company to develop a research dissertation on water sustainability. This has been an invaluable learning experience and allowed me to gain a greater understanding of their Replenish Africa Initiative (RAIN) programme in Africa. We have some interesting ideas which I will be developing over the winter break. When I say ‘break’, this is a bit of euphemism as the work continues with various assignments and readings, including preparation for next term. I have been dying to experience snow for the first time so hopefully this will provide an exciting interlude to my studies!

While working with communities on water supply back in Kenya, I had a strong desire to develop solutions for the challenges encountered and learn how Europe was able to overcome such problems and achieve its high level of water resource development. In this respect, Oxford is providing me with a firm foundation. I am learning from distinguished teaching staff with extensive experience in policy and practice, most interestingly on how to formulate cutting-edge solutions to water challenges facing Africa. When I return to Africa, I will take this knowledge with me. I look forward to making a positive difference in addressing the water challenges my continent faces.

This is the first in a three-part blog series. Read Cliff’s second and final blogs.


The hidden resource: groundwater’s role in achieving water security

Groundwater is critical to global water security. This was the clear message Professor Richard Taylor delivered at a seminar in Oxford on 13 November.

Knowledge gaps in groundwater science

Water stored underground provides around 36% of the world’s domestic supplies, and 42% of all irrigation water. Use of groundwater could also prove a useful adaptation to climate variability and change, Taylor said.

Despite its strategic importance, our understanding of the magnitude of groundwater resources across the world is strikingly poor. A groundbreaking 2012 study by Taylor and colleagues showed that the volume of groundwater in Africa is 10-100 times greater than water found above the surface. Far greater investment in groundwater monitoring and science is needed, if this resource is to be harnessed to achieve water security.

Climate change impacts on groundwater recharge

While knowledge on the current state of groundwater is patchy, still less is known about how these resources will change into the future. It is unclear how the trend towards more frequent and heavy rainfall events expected as global temperature rises will impact groundwater recharge.

The 2007 IPCC Fourth Assessment Report referred to just one study on the impact of climate change on groundwater, which projected a dramatic 70% reduction in groundwater recharge in some parts of Brazil and Africa. The model used assumed that more intensive rainfall would more often exceed the capacity for water to infiltrate soils.

However, Taylor provided stark evidence to the contrary, suggesting that more heavy rainfall events may in fact lead to greater groundwater recharge. This more optimistic outlook was based on a study of 55 years of observational data of rainfall and groundwater levels in semi-arid Tanzania.

The records from Tanzania show that recharge is closely associated with extreme seasonal rainfall, with only seven rainfall events during the 55 years accounting for 80% of the recharge. Increased use of groundwater could therefore prove a useful adaptation to climate variability and change, suggested Taylor.

Sustainability of groundwater use

In Bangladesh, China and India, tapping into groundwater reserves for irrigation has enabled these countries to dramatically increase food production to meet the needs of their expanding populations.

However, groundwater is being used faster than it can be replenished in some parts of the world, warned Taylor, including north-west India, the California Central Valley, and the North China Plain. Indirect impacts on groundwater, for example due to irrigation demand, can outweigh any direct impacts of climate change on recharge rates. The sustainability of resources therefore remains a key concern.

Groundwater depletion is not always inevitable and in some cases, groundwater abstraction can actually lead to greater recharge. Taylor’s research shows that in parts of the Bengal Basin in Bangladesh, water pumped out of the ground is almost completely replenished by the yearly monsoon. The subsurface effectively acts as a storage reservoir, with pumping during the dry season making space for greater storage and recharge during rainy periods.

Whether abstraction leads to groundwater depletion or increased recharge depends on the geology and soils, with sandy soils being favourable to recharge in the Bangladesh case.

The inadequacy of global water scarcity metrics

Current metrics of freshwater availability are based solely on river flows. According to Taylor, these measures are fundamentally flawed as they ignore groundwater, and therefore warp perceptions of water security.

Water scarcity metrics are also unhelpful when it comes to planning for adaptation to climate change. Using water more efficiently, and increasing storage, can both help buffer increasing varibility in flows. “We need to think of storage more holistically”, said Taylor. This means considering not only constructed storage such as reservoirs, but also the water stored naturally beneath the Earth’s surface.

This blog is based on a talk given by Richard Taylor, Professor of Hydrogeology at University College London, as part of the Water Security, Growth and Development seminar series. Download the presentation slides