Tom Gleeson

I am a hydrogeologist at University of Victoria, Canada who is interested in groundwater sustainability, mega-scale groundwater systems, groundwater recharge and discharge and fluid flow around geologic structures. My goal is fundamental and applied research and teaching to enable sustainable groundwater use.

What is the volume (in kegs) of groundwater is stored on earth?

What is the volume (in kegs) of groundwater is stored on earth?

Last week I gave a ‘blue drinks’  presentation for a networking evening for the Victoria chapter of the Canadian Water Resources Association entitled “How much groundwater is on earth?” based on our paper from Nature Geoscience last year. Since the night was hosted at Philips Brewery, an awesome local brewery (who makes Blue Buck, the perfect blue drink, and lots of other great beer), I decided to calculate how many kegs of groundwater we have on earth or said another way “what is the volume (in kegs) of groundwater is stored on earth?

So this blog post is a skill-testing question for all the nerds out there – answer below in the comments knowing:
a keg is 58.7 liters = 5.87e-11 km3 so there are 1.7 e+10 kegs in a km3.

Hint it is more than 1.7 e+10 kegs…. and one person during the evening got it almost correct.

Research mini-conference in fourth year groundwater class

Research mini-conference in fourth year groundwater class

Fourth year and graduate students led a fun mini-conference during class in Groundwater Hydrology (CIVE 445, Civil Engineering at University of Victoria) yesterday. Local consulting and government hydrogeologists joined, making the students both nervous and excited to be presenting to professionals with up to forty years of groundwater experience. The presentations were the culmination of a term-long independent group research project – they also write a research paper (which is peer-reviewed by their classmates). And the mini-conference culminated in beers at the grad club, unfortunately drinking beer brewed with surface water.

It seemed like a win-win-win for everyone. The students loved meeting and presenting to, and being grilled by, the people who had mapped the aquifer they were modeling or asked if their model is based on any real data. The practitioners loved seeing the new ideas and enthusiasm of the students. And I loved seeing the interaction and learning.

For any prof reading this, here is a description of the Group Research Project and the conference poster:






Socio-hydrogeology: bridging the gap between science and society

Socio-hydrogeology: bridging the gap between science and society

Authored by Viviana Re, Marie Curie Research Fellow at Ca’ Foscari University of Venice, Italy

Sustainability, integrated water resources management, climate change, groundwater governance. These are some of the currently trending topics in hydrogeology, as reflected by their widespread use as keywords in recently published literature. Indeed, hydrogeologists are at the forefront of guaranteeing the long-term sustainability of aquifers worldwide. But how can they assure that the outcomes of their investigations are really translated into effective science-based management practices? How can they make sure that their work really reaches water end-users and all those eventually affected by new water quality and quantity control measures?

Possibly the most effective way is to commit themselves to bridging gaps between science and society.

This is the aim of “socio-hydrogeology”, a new approach to groundwater investigations promoting the incorporation of the social dimension into hydrogeological studies willing to provide management practices with better support (Re, 2015).

Socio-hydrogeology proposes the coupling of robust hydrogeological investigations with a more comprehensive assessment of the socio-economic implications of the (ground)water problems in question. In agreement with the general definition of socio-hydrology—the science of people and water (Sivapalan et al. 2011)—socio-hydrogeology aims not only at studying the mutual relations between people and groundwater (i.e. the impact of human activities on the baseline characteristics of an aquifer and the impact of groundwater—its quality, its presence and scarcity—on human well-being and life), but more generally to include social dimensions in hydrogeological investigations. This means ensuring that the results of scientific investigations are not only based on real needs and local knowledge, but are also adequately disseminated to groundwater users .

Hydrogeologists can be leaders in socio-hydrogeology. They can advocate for groundwater management and protection. They can promote bottom-up approaches that embed local know-how into management strategies. As many hydrogeologists spend substantial time in the field, they are generally the first point of contact for well holders, farmers and other groundwater users. They may therefore act as mediators between theory and practice, or between the problem and the (potential) proposed solution to issues of sustainability and pollution. This is why allocating specific time to structured interaction with the relevant stakeholders and water users prior to and during hydrogeological investigations, they can maximize the use of hydrogeological information and outcomes, which are obtained, in the best cases, with the best available technology and tools.


Socio-hydrogeology in practice:  in situ measurements and interviews with farmers (Cap Bon, Tunisia; Viviana Re, 2014)

This newly established field allows hydrogeologists to focus on mutual relations between groundwater and society and to foster both ‘horizontal’ (e.g. between state and non-state actors or across sectors such as agriculture or energy) and ‘vertical’ (between various levels) cooperation. This novel approach presents a standardized baseline method focused around hydrogeologists, which is easy to understand, flexible, not too time-consuming, and offers the chance to implement preliminary public engagement with limited effort.


Discussions about water issues with farmers near Grombalia, Tunisia (Viviana Re, 2014).

In this framework, the Bir Al-Nas (Bottom-up IntegRated Approach for sustainabLe grouNdwater mAnagement in rural areaS*) approach is proposed as an initial attempt to put the concept of socio-hydrogeology into practice through hydrogeological and social analysis, the latter performed by means of a social network analysis and structured interviews with the people involved in the groundwater monitoring network. Bir Al-Nas is currently being tested and implemented in the Grombalia Basin (Tunisia), chosen as representative of the issues shared by most of the coastal aquifers in arid/semi-arid regions (i.e., aquifer pollution and salinization, water overexploitation, saline-water intrusion, and agricultural return flow).

*Research supported by a Marie Curie International Outgoing Fellowship within the EU 7th Framework Programme for Research and Technological Development (FP7-PEOPLE-2012-IOF, project reference 327287).

 –Featured image by Chiara Tringali (2014)

Brackish groundwater resources: is development advisable?

Brackish groundwater resources: is development advisable?

Authored by: Grant Ferguson – Assistant Professor in the Department of Civil & Geological Engineering at the University Saskatchewan

Groundwater makes up a large fraction of the Earth’s freshwater but that represents only a part of groundwater resources. Large volumes of groundwater are saline, with some reaching salinities of over ten times that of seawater. Brackish water is an intriguing part of the spectrum of groundwater resources, sitting just beyond the water quality salinity requirements for potable water. Many water scarce regions are considering the use of brackish groundwater, sometimes as a potable water resource via desalination or for industrial use where quality requirements are less restrictive. Recent studies by International Groundwater Resources Assessment Centre and the United States Geological Survey showed that these resources are relatively accessible in many areas around the globe.  For example, significant brackish groundwater is present at less than 500 feet below ground surface throughout most of the Great Plains.


Distribution of saline groundwater resources in the contiguous United States. (image source).

Using brackish water certainly increases the amount of groundwater in storage that is usable, however what remains unclear is how this fits into the construct of groundwater management. Following ideas promoted by John Bredehoeft, pumped groundwater must be balanced by either an increase in recharge, a decrease in discharge or reduction of storage.  Typically, brackish water systems do not receive large amounts of recharge, nor are they well connected to surface water bodies. This suggests that most brackish water developments are mainly supported by withdrawal of water from storage and that the development of brackish water resources at large scales over longer time frames will result in groundwater depletion problems.

Given this possibility, is development of brackish groundwater resources advisable?


Some situations — such as auxiliary water supplies used during times of drought or high demand, and perhaps most notably for some regions, oil and gas development — only demand groundwater supplies for finite duration — for periods of months to a few years.  Both the Province of Alberta and the Canadian Association of Petroleum Producers have recently promoted such initiatives in oil and gas producing regions in Canada. However, the oil and gas industry has been using brackish and saline water in Canada for several decades.  During the 1970s, a few wells, installed across a small area in Saskatchewan and the Judith River Formation, pumped brackish water at high rates before they had to be abandoned due to excessive water table drawdown.  Other wells in the area have been used more or less continuously for the last few decades to support enhanced oil recovery, where water levels have not dropped to the point that these wells also need to be abandoned.  Simulations suggest that hydraulic heads have decreased by a few meters across distances of several kilometers from these pumping wells, however this regional drawdown has not been well documented (due a lack of monitoring) nor have water levels in the hundreds of wells in the shallow groundwater systems above Judith River Formation declined noticeably.

One hell of a great groundwater textbook now available free

One hell of a great groundwater textbook now available free

‘Groundwater’ the seminar text book from Freeze and Cheery (1979) is free in pdf now…just follow the links here. This text book is almost as old as I am and important parts of modern hydrogeology are rusty or non-existent (like hydroecology amongst other topics) but it is still lucidly written and useful.  I routinely send students to read chapters so I am happy that it is now available free.

Kudos to Pearson Publishing, Alan Freeze and John Cherry and Hydrogeologists without Borders! I look forward to Groundwater2.0 which is in the works!



The new and exciting face of waterunderground.org

The new and exciting face of waterunderground.org

by Tom Gleeson

I started waterunderground.org a few years ago as my personal groundwater nerd blog with the odd guest post written by others. Since I love working with others, I thought it would be more fun, and more interesting for readers, to expand the number of voices regularly posting. So here is the new face of the blog…


a kind of weird image of collective action

What is the new blog all about?

Written by a global collective of hydrogeologic researchers for water resource professionals, academics and anyone interested in groundwater, research, teaching and supervision. We share the following aspirations:

  • approachable groundwater science at the interface of other earth and human systems
  • encourage sustainable use of groundwater that reduces poverty, social injustice and food security while maintaining the highest environmental standards
  • compassionate, effective supervision
  • innovative, effective teaching
  • transparency of scientific methods, assumptions and data

Check out more details and how to be part of the blog on about.

Frequent contributors include:

  • Andy Baker (University of New South Wales, Australia) – caves and karst (I actually visit the water underground!), climate and past climate
  • Kevin Befus (University of Wyoming, United States) – groundwater-surface interactions, coastal groundwater, groundwater age
  • Mark Cuthbert (University of Birmingham, United Kingdom) – groundwater recharge & discharge processes, paleo-hydrogeology, dryland hydro(geo)logy, climate-groundwater interactions
  • Matt Currell (RMIT University, Australia) – isotope hydrology; groundwater quality; transient responses in aquifer systems
  • Inge de Graaf (Colorado School of Mines, United States) – global groundwater withdrawal, flow and sustainability
  • Grant Ferguson (University of Saskatchewan, Canada) – groundwater & energy, regional groundwater flow, sustainability
  • Tom Gleeson (University of Victoria, Canada) – mega-scale groundwater systems and sustainability
  • Scott Jasechko (University of Calgary, Canada) – global isotope hydrology; groundwater, precipitation, evapotranspiration
  • Elco Luijendijk (University of Gottingen, Germany) – paleo-hydrogeology,deep groundwater flow,large scale groundwater systems
  • Sam Zipper (University of Wisconsin – Madison, United States) – ecohydrology, agriculture, urbanization, land use change

Nature Geoscience digging into water underground this month!

Nature Geoscience digging into water underground this month!

Nature Geoscience is digging hard into water underground – the February issue is part of a special focus on groundwater. The cover this month is a gorgeous (groundwater-filled?) waterfall by Glen Jasechko, Scott’s brother.  The groundwater focus includes:

As part of the focus the journal made our paper on modern groundwater free to registered users for a month – so go download it an check out this and the other papers too!


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