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Protecting springs from groundwater extraction: is a ‘drawdown trigger’ a sensible strategy?

Protecting springs from groundwater extraction: is a ‘drawdown trigger’ a sensible strategy?

By Matthew Currell – Senior Lecturer at RMIT University

Springs, some of which have been flowing for hundreds of thousands of years, have been disappearing in Australia due to human water use over the past century. Following a hotly contested court case, Australia’s Environment Minister imposed a 20cm ‘drawdown limit’ at a set of springs, to protect them from a proposed coal mine. However, this ignores a fundamental principle of hydrogeology, known as ‘capture of discharge’ and as a result, the springs may still be under threat.

Why are springs important?

Springs are a groundwater system’s gift to the surface.  They provide a constant source of water to the landscape throughout the year, and many have been doing so for millenia. This is why they are often of great importance to indigenous people and why they play an important part in the history of human settlements. Springs also provide valuable ecological refuges in dry landscapes and are often home to endemic species. However, springs are vulnerable to the effects of groundwater extraction.

The disappearing springs of the Great Artesian Basin

Recently, a group of Australian ecologists and hydrogeologists published a study of ‘lost springs’ that have disappeared from the Australian landscape since European settlers began drilling for water and minerals in the Great Artesian Basin (GAB) – the world’s largest artesian aquifer system (the term ‘artesian’ means that when a wellbore intersects one of the aquifers, groundwater flows freely to the surface, often gushing meters up into the air). Groundwater in the Great Artesian Basin travels many hundreds of kilometres across the Australian continent, before surfacing as clusters of springs, which provide life in otherwise dry landscapes (Figure 1). Research by colleagues of mine estimates that some of these springs have been discharging water (at variable rates) for hundreds of thousands of years.  This is based on dating the minerals that have been continuously precipitating at the spring outlets over geologic time. The drilling of wells in the Great Artesian Basin began in the late 1800s and was encouraged by governments, as a way to ‘open up the landscape’ for further white settlement into the country’s harsh, arid interior. Many of these artesian bores were allowed to flow freely for decades (some are still uncapped), leading to major declines in groundwater pressures throughout the Great Artesian Basin. Sadly, this has also caused many springs to disappear.

Great_Artesian_Basin

Figure 1 – Map of Australia’s Great Artesian Basin, which covers four states, showing the major areas of groundwater recharge and discharge, where springs emerge at the surface.  Source: ABC Science: http://www.abc.net.au/science/articles/2012/04/04/3470245.htm

Recent threats to springs from mining

More recently, another human activity threatens springs – mining. In particular, parts of Australia have recently experienced a boom in coal seam gas and large coal mining proposals. Large volumes of groundwater must be pumped from the aquifers above and adjacent to the coal and gas deposits to allow them to be mined. Extracting groundwater for mining means that some water that could otherwise reach the surface at springs is re-directed towards the gas wells or mine pits.  Figure 2 shows a map of oil and gas exploration and production permits that currently cover the Great Artesian Basin. Many of these are yet to be developed but would involve significant groundwater extraction.

Great_Artesian_Basin2

Figure 2 – Map of the Great Artesian Basin showing active oil and gas leases. From: SoilFutures Consulting, (2015): Great Artesian Basin Recharge systems and extent of petroleum and gas leases (2nd ed)

Recently, a major international company has also proposed the largest coal mine in Australia’s history – the Carmichael Coal Mine & Rail Project. Within 10 kilometres of the proposed mine site is a group of Great Artesian Basin springs – the Doongmabulla Springs. These springs are an ecological refuge, providing an oasis of green in an otherwise dry landscape (as can be seen in drone footage here: https://www.youtube.com/watch?v=RglMko3GwQA). The springs are of high cultural and ecological significance to the local Indigenous Wangan and Jagalingou people, and for this reason (among others) these people are strongly opposed to the mine.

Colleagues of mine recently participated in a hotly contested court case, arguing over whether or not the Carmichael Mine poses a threat to the survival of the Doongmabulla Springs – recognised by the Land Court judge as having ‘exceptional ecological significance’. The argument centred on whether or not the springs are fed by water from the same group of aquifers that will be excavated and de-watered by mining, or shallower aquifers. Ultimately, the Court decided that the mine was unlikely to pose an imminent threat to the springs, and upheld the environmental authority that was earlier granted by the Australian Government. This was in spite of testimony of some expert hydrogeologists that the most likely explanation for the springs is a fault that brings deep groundwater to the surface (more about the case and the mine can be read here).

Protection of Great Artesian Basin Springs

In Australia, the native flora and fauna supported by Great Artesian Basin springs are protected under the country’s highest piece of environmental legislation – the Environment Protection and Biodiversity Conservation Act (1999). This recognises the extraordinary level of endemism in these spring systems – many support species that are found in a single spring pool or group of springs, and nowhere else on earth. If a mining project is located in an aquifer that supports ‘GAB Springs’, the Act specifies that the Environment Minister must impose conditions to protect the springs’ water source. The mining company must then develop a monitoring and management plan, and a set of contingency measures to ensure impacts can be minimised.

In order to protect the Doongmabulla Springs from potential impacts of the Carmichael mine, the Environment Minister chose to apply a drawdown limit or ‘trigger’ level of no more than 20cm, stating:

“I took a precautionary approach by imposing a drawdown limit of 20 cm at the Doongmabulla Springs Complex (condition 3d), to ensure that there are no unacceptable impacts to the springs”

Problems with a drawdown ‘trigger’ to protect springs

Limiting drawdown to 20cm at a spring may sound like a strict criterion to ensure minimal impact from groundwater extraction (as this is a relatively small change in the water level). However, the approach has a number of pitfalls, as I recently outlined in a technical commentary in an article for the journal Groundwater.

The drawdown ‘trigger’, applied at the springs themselves, ignores one of the fundamental principles of hydrogeology, which is that groundwater extraction affects aquifers in two major ways; firstly through depletion of water in storage, and secondly through capture of discharge. All groundwater and surface water systems are subject to a ‘water budget’, whereby an increase in extraction at one point leads to a corresponding decrease in water stored or water available somewhere else. It has long been recognised that when groundwater extraction begins, there is generally a period in which storage depletion – shown by declining groundwater levels in the aquifer near the extraction point – is the dominant effect. However, in the long-term, extraction is balanced mostly by a decrease in the discharge reaching the surface. It is the ‘capture of discharge’ which is the most important effect to consider when protecting springs from pumping – as spring water is entirely composed of groundwater discharge. Unfortunately, this ‘capture’ is not well predicted by monitoring the amount of drawdown, particularly at the point of discharge itself.

As Figure 3 below demonstrates, it is quite possible for a spring (or a gaining stream) to experience minimal drawdown, but for the flow of water from the aquifer to the surface to decrease or even cease entirely. For this reason, by the time 20cm of drawdown has been noticed at the Doongmabulla Springs – which are located about 8 kilometres from the mine site – it is likely that the flow directions and water budget will have been fundamentally changed, and possible that the springs may ultimately cease to flow, as has occurred in many other parts of the Great Artesian Basin.

fig3

Figure 3 – Example of how groundwater levels change during groundwater extraction.  Drawdown may be small at a spring or stream until it is too late (fr: Currell, 2016).

Alternative approaches to management and protection of springs

It can be argued that the setting of a drawdown ‘trigger’ at a spring or stream is a classic case of ‘reactive’ environmental management, whereby management action is taken only in response to an impact when or after it takes place. Because of the relatively high level of uncertainty in most hydrogeological systems, the time-lags that occur between an activity such as pumping and the hydrological response, and the difficulty in directly observing groundwater behaviour, a pro-active approach to monitoring and managing impacts from mining and other activities is needed. As I argue in the technical commentary, a far more effective approach to springs protection would include a program to understand the source aquifer for the springs, an assessment of the water budget before and after the mining development (through modelling), and a monitoring program that maps out water level patterns and flow directions in the aquifer(s) regularly through time and also monitors flow rates at the springs. These activities should be undertaken up-front during the environmental impact assessment. If ‘trigger’ levels are to be used as an effective management tool,  these should be set as specified water levels at a series of points set back some distance from the springs, to identify negative effects before they reach the springs.

While this may sound onerous for the mining company, the importance of the springs to the indigenous people and ecological environment means that it is worth making the effort to use the best hydrogeological science possible to protect them.

Bonus Figures
bonus1

Artesian well in the Great Artesian Basin providing a constant flow of hot water. (Source: Wikipedia commons)

bonus2

Evidence of springs that have gone dry, from sites in Australia’s great Artesian Basin.  From: Fensham, R. et al., 2015 In search of lost springs: a protocol for locating active and inactive springs. Groundwater Volume 54, Issue 3, pagese 374-383, 5 October 2015 DOI: 10.1111/gwat12375 (link)

Human Drought?

Human Drought?

By Anne Van Loon – a water science lecturer at the University of Birmingham

Recently I published a commentary in Nature Geoscience with the title ‘Drought in the Anthropocene’. In that commentary, my co-authors and I argued that in the current human-dominated world, we cannot study and manage natural drought processes separately from human influences on the water system like water abstraction, dam building, land use change, water management, etc. To fully integrate human processes when studying drought we should change the definition of drought, test new methodologies and include social science. This sounds quite logical, but if you look at the history of drought science, it is not so obvious. In the natural sciences, drought research is a young field compared to research on floods. Floods are of course much more conspicuous, but drought causes more loss of life and economic damage worldwide. Because drought research is such a young field, the basic processes needed to be studied first before complex systems (including humans) could be understood. Additionally, much of the drought research in the last decades has focused on questions related to the effects of climate change, which needed natural case study regions, uninfluenced by people, for an undisturbed climate change signal.

So why do I think it is time for a change now? Well, partly because the drought research field is a more mature field now and because we realize that direct human influences on drought might be significantly bigger than the effects of climate change, but there is a personal story too. That story starts when I started my PhD on the processes underlying drought propagation at Wageningen University (the Netherlands) in 2007. I was going to focus on natural processes and five case study regions were selected in the EU-funded project I was working in. One of those ‘unfortunately’ was not a natural, undisturbed catchment. In the Upper-Guardiana catchment in Spain abstraction for irrigation in the 1980s and 1990s was so massive (see pictures below) that it decreased groundwater levels with 50 meters in some parts of the aquifer and groundwater-dependent rivers dried up (see pictures below).

A

Large-scale agriculture (mainly grapes) requiring large-scale irrigation in the Castilla-La Mancha region in Spain

 

B

Dried-up rivers in the Guadiana catchment. The name of the river is even crossed out because there has not been any wate rflowing for 20 years. (Photos by Henny Van Lanen)

When the important Ramsar wetland Tablas de Daimiel dried up (see pictures below), this led to a debate between farmers and nature organisations. The nature organisations claimed this disaster to be caused by the agricultural abstractions, whereas the farmers defended themselves by arguing that the wetland dried up because of the severe multi-year drought that Spain was experiencing at the time and that their abstraction was only minimal. Since I was interested in the natural processes related to the development of that drought, I needed to exclude the effect of abstraction. I developed a methodology for that and discovered that the drying up of the wetland was caused by both a lack of precipitation and groundwater abstraction, but that the effect of groundwater abstraction on decreased water levels was, on average, four times as high as the effect of the lack of precipitation. This meant that both the farmers and the nature organisations were right, but the farmers had more influence than they claimed to have.

C

Dried-up wetland Tablas de Dimiel. (Photos by Henny Van Lanen)

This approach of separating between the human and natural causes of a lack of water solved the problem for my PhD and I could comfortably go back to studying the natural processes of drought in all my case study regions. And I did so successfully, judged by the positive evaluation of my PhD thesis and defence in 2013 (see pictures below). However, something kept bothering me, because I realized that my results were not applicable to most of the world, since there are almost no places left without significant human influence on the water system.  Take the current multi-year drought in California. Politicians, farmers, water managers and the media keep asking the question: “how much rain is needed to end the drought?” This would already be quite a difficult question in a completely natural system, but it is un-answerable in a hugely complex system like California, dominated by human activities like agriculture, water abstraction, water storage in reservoirs, water transfer, and urbanization. How much rain is needed to end the drought is for example highly dependent on how much we abstract. With a simple water balance you can evaluate that the amount of water storage (in for example groundwater or reservoirs) is related to how much water comes in and how much water goes out. If we take out more, we also need more input to recover from a drought in storage. So, if the farmers in California keep on abstracting huge amounts of groundwater, the system will take much longer to recover. We as natural scientists cannot answer questions about the recovery of drought in these kind of human-dominated systems if we do not take into account human activities in our calculations. To be able to do that we need to adapt our methodologies. We could for example use the tools I used to get rid of human aspects of drought in my Guadiana case study, to instead focus on the effect of abstractions.

D

PhD thesis and defense.

But it is not all bad. We can also have a positive influence on drought. Last year (already moved on to a Lecturer post at the University of Birmingham, UK), I visited Santiago de Chile for a project workshop. Santiago is a very big city (see pictures below). For its water supply the city is dependent on snow and reservoirs in the mountains. Decreasing snow accumulation related to climate change lead to worries about future water resources. One of the solutions the Chileans are investigating is artificial aquifer recharge projects, in which surface water during high-flow periods is led to infiltration ponds and allowed to recharge the underlying aquifer (see picture below). In times of low water availability in the mountains this groundwater can be used as alternative source of water.

E

The city of Santiage de Chile and their Artificial Aquifer Recharge project.

Also in Upper-Guadiana, people have found a solution to the problem. Measures are in place to reduce groundwater abstraction for irrigation. However, these take a long time to implement and to have an effect on groundwater levels and the wetland. Until that time, a temporary solution saves the important wetland from drying out completely. Groundwater is pumped up to keep the Tablas de Daimiel wetland wet (see pictures below). Hopefully this is a bridge to a more sustainable solution that results in a full recovery of the aquifer and the wetland.

F

Re-wetted wetland Tablas de Daimiel.

These positive influences of humans, alleviating drought conditions, should also be included in our drought research, because then we can investigate the effectiveness of certain measures to reduce the impacts of drought. Responses to drought, such as water use restrictions, can lead to feedbacks between the natural and social systems that are very complex, but also very interesting and crucial to understand if we want to solve our drought problems. That is why I wrote the Nature Geoscience about such an obvious topic ‘Drought in the Anthropocene’. I am ready to work on more complex drought processes (see pictures below) and I encourage my colleagues to do the same so that our results are useful where they are most needed.

G

Me looking towards a bright future … (Photos by Henny Van Lanen)

Read the paper ‘Drought in the Anthropocene’ here: http://www.nature.com/ngeo/journal/v9/n2/full/ngeo2646.html


Van Loon, A.F., Gleeson, T., Clark, J., Van Dijk, A., Stahl, K., Hannaford, J., Di Baldassarre, G., Teuling, A., Tallaksen, L.M., Uijlenhoet, R., Hannah, D.M., Sheffield, J., Svoboda, M., Verbeiren, B., Wagener, T., Rangecroft, S., Wanders, N. and Van Lanen, H.A.J. (2016). Drought in the Anthropocene. Nature Geoscience, 9(2), pp.89-91.


~ A repost from the TravellingGeologist blog ~

Can we use an infrared camera to tell us how much groundwater is coming out of the side of a cliff?

Can we use an infrared camera to tell us how much groundwater is coming out of the side of a cliff?

By Erin Mundy – a plain language summary of part of her Masters thesis

Groundwater is an important resource, with approximately 2 billion people around the world using groundwater everyday. Although most groundwater is beneath our feet, sometimes groundwater leaks out of stream-banks, hill sides and cliff faces – this is called groundwater seepage. Current scientific methods are not able to measure the amount of groundwater that leaks out of these landscapes. Scientists have used infrared cameras (cameras that show the heat of an objects) to identify groundwater seepage on hill-slopes and stream banks (Figure 1).

seep1

Figure 1. Digital image (a) and temperature image (b) of a seep in the summer and a digital image (c) and temperature image (d) of the same seep in the winter

This is because groundwater has an distinct heat signal, having a relatively constant temperature throughout the year (~10 degrees Celsius). Building on these studies, we hoped to find out the possibilities and limitations of using infrared cameras to measure the amount of groundwater that leaks out of the side of a cliff. We wanted to test if groundwater was flowing out of a cliff face slowly in the summer would warm up as it traveled down the rock, so the heat signature of the groundwater would go from cool water (that comes out of the rock, ~10 °C) to warmer water (warmed due to the sun and air temperature). On the other hand, we wondered if groundwater was flowing fast out of the cliff-face, it would not have time to warm, because the cool groundwater would be consistently running over it. In the winter, we believed the opposite would happen, that the groundwater would be warmer, relative to the surroundings, and show a cooling trend as the water traveled down the rock.

 

We found an unused mining pit in Saint Dominique, Quebec, that had lots of groundwater seeps coming out of the exposed rock, and used this as our test location. The mining pit had 3 different levels, as shown in Figure 2.

seep2a

Figure 2: an aerial shot of the quarry with the seeps labeled.

We took infrared and optical photographs of the seeps during seven visits that spanned from January 2013 – October 2014. Three visits took place during the winter (January – February 2013), coinciding with periods of below freezing so that the effect of extreme cold on seeps could be analyzed. Four visits took place during the summer/fall (June – October 2014), coinciding with sunny and hot conditions, and cloudy and warm conditions in order to determine the effect warmer temperatures have on seepage. In addition to these visits, we also completed a 24-hour experiment, where we took infrared pictures of two seeps every half hour for 24-hours, to determine the effect of sunlight and changing air temperature on the seep temperature signature. We also created an “artificial seep” experiment, where we released water from two large tubs over the cliff at the pit for 8 hours; one tub had water released at a slow rate, while the other at a faster rate, to see if we could replicate the heat signals from the real seeps. We took pictures with the infrared camera every half hour for eight hours for that experiment. We analyzed the infrared photos from each visit using a computer software that allowed us to determine the temperature along the seep.

In the winter, groundwater flows out the rock at warmer temperatures than it’s surroundings, making it easily distinguishable. We found that there was a clear relationship between seeps with active groundwater flow and areas of ice growth on the following visit. So, in the winter, if you use an infrared camera to locate where groundwater is flowing on the side of a cliff, you can assume there is a good chance that ice will eventually form at these spots. However, the groundwater did not cool along the rock face, as we had expected it would. This suggests frozen seeps are complex and it is unlikely that temperature pictures can determine the rate of flow of groundwater seeps in the winter.

In the summer, we found that lower flowing seeps did warm up as the water traveled down the rock face, as compared to faster flowing seeps, which did not show as much warming. However, in the 24-hour experiment (where we took infrared pictures every half hour for 24 hours of two seeps), we found that the temperature signature of the seeps changed throughout the day. During the day, there was much more warming of the groundwater as it traveled down the cliff, whereas at night it did not warm as much. This is most likely due to the presence of sunlight and warmer air temperature during the day, which warms the water more as it is traveling down the rock.

In the “artificial seep” experiment, we found that the “seeps” showed more warming than the real seeps. This is probably because we only ran the experiment for 8 hours, so it did not have time to mimic the conditions of real seeps. Also, we noticed that instead of flowing down the rock face, some of the water was actually seeping into the rock, along the breaks in the rock. This may be another reason why the seeps showed more warming, as not enough water was flowing down the rock (instead it was flowing into it).

After completing these experiments, we have concluded several possibilities and limitations for infrared pictures of groundwater seeps.

Possibilities:

  • Locate groundwater seeps in all seasons
  • Locate groundwater seeps in winter and from this, areas of ice growth can be predicted
  • Distinguish between lower flowing seeps and higher flowing seeps in summer (lower flowing seeps have more warming as the water travels down the rock face, higher flowing seeps do not have as much warming)

 Limitations:

  • Need to have a large difference in temperature between the air and groundwater to notice seeps. During the third winter visit, only one seep was identified to be flowing by the infrared camera. However, visual observations showed that eight seeps had groundwater flowing. This is because the temperature of the groundwater was too similar to the temperature of the air, making it not possible to detect the groundwater flow.
  • Groundwater seeps in the winter are complex and do not show a cooling trend, therefore it is unlikely that temperature pictures can determine the rate of flow of groundwater seeps in the winter
  • Breaks in the rock affect the flow of seeps, redirecting the flow, making it hard for temperature pictures to accurately determine flow
  • Sunlight and air temperature affect the “warming” and “cooling” of the groundwater flow, with more warming present during the day and less at night. Focus needs to be on determining the optimal time to use infrared pictures to show the “warming” (or “cooling”) trend.
  • The infrared camera itself has limitations. To use some functions of the camera, you have to correct your data for certain factors (like angle of the camera, humidity, etc.). If you don’t, you won’t be showing accurate data. This limits the amount of things you can do with the infrared camera and must be taken into account in order to ensure the pictures you captured are correct.

 

Despite the large number of limitations, infrared pictures is effective at locating groundwater seeps in all seasons, and able to distinguish between lower flowing seeps and higher flowing seeps (in the summer), which makes this technique a valuable, non-invasive way to study groundwater seepage. Future work should look at determining the optimal time to capture infrared pictures of seeps to determine a relationship between groundwater flow and temperature signatures.

 


 

Baseflow, groundwater pumping, and river regulation in the Wisconsin Central Sands

Baseflow, groundwater pumping, and river regulation in the Wisconsin Central Sands

By Sam Zipper, postdoctoral fellow at Madison and author of tacosmog.com

We often think of groundwater as a nonrenewable reservoir, deep underground, and with good reason – less than ~6% of groundwater globally entered the ground within the past 50 years. However, where a river or stream intersects the water table, water is able to move from the aquifer to the stream (or vice versa). This supply of shallow groundwater to streams is called ‘baseflow’, and is an important supply of water for many streams worldwide, especially during dry seasons or periods of drought. Below, we can see that baseflow makes up more than 50% of total streamflow over most of the world:

global_baseflow

Global estimates of baseflow index – the proportion of streamflow that comes from groundwater or other slowly varying sources, like upstream lakes and wetlands.

The ability of groundwater to contribute to streamflow depends on the water level of the aquifer in the area surrounding the stream. Therefore, human actions that lower groundwater levels (such as pumping for urban or agricultural use) can impair the ability of an aquifer to supply water to streams during dry periods, with potentially devastating consequences for streamflow.

One example close to my home is the Central Sands region of Wisconsin, which is a large region found (not surprisingly) in the center of the state with particularly sandy soils. The sandy soils are perfect for growing potatoes, and the Central Sands is primarily an agricultural region; however, because water drains quickly from sandy soils, irrigation has become an increasingly important part of the landscape:

centralsands

In addition to agriculture, however, the Central Sands region is home to many rivers, lakes, and streams. Recently, one river in particular has become a microcosm of the debate surrounding the impacts and trade-offs of agricultural water use: the Little Plover River. While only 6 miles long, the Little Plover is a prized brook trout fishery and important ecosystem within the region. According to American Rivers, which listed the Little Plover as one of America’s 10 most endangered rivers in 2013, streamflow in the Little Plover has been decreasing since the 1970s and flows today are roughly half of the historical normal. The situation in the Little Plover came to a head in 2005, when several stretches of the Little Plover dried up, with predictably negative consequences for the fish.

Over the past decade, the Little Plover has been mired in legal controversy. In 2009, the Wisconsin Department of Natural Resources established what they call a “Public Rights Flow”, or a required amount of streamflow that the public is entitled to flow through the river. The advocacy leading to the establishment of this Public Rights Flow was primarily by conservation groups like the River Alliance and Trout Unlimited, with the goal of protecting fish and the rest of the stream ecosystems. In order to set the threshold, the Wisconsin Department of Natural Resources first established a baseline level as the 7-day average low flow with a 10% probability of occurring in a given year, and then adjusted this value upwards based on estimates of the flow necessary for to provide fish habitat and recruit trout. Despite the positive step of establishing a Public Rights Flow, measurements during the 2012 drought were consistently below the thresholds set by the Department of Natural Resources, and the Little Plover even dropped below the thresholds in 2013 and 2014, both of which were relatively wet years for Wisconsin.

plover

The Little Plover in 1997 and the first time in ran dry in 2005 (Friends of the Little Plover)

The current debate surrounding the Little Plover hinges on whether the Department of Natural Resources is legally allowed to consider cumulative impacts when permitting new high capacity wells in the region. Previously, the Department of Natural Resources was not considering cumulative impacts, which means that for every well application, they are only allowed to think about that well in isolation – and the effects of a single well are typically small enough that the Department of Natural Resources does not have sufficient grounds to deny a permit. However, the relatively small impacts of many individual wells can add up to cause a big overall effects on local groundwater resources. This changed in 2014, when a judge ruled that the Department of Natural Resources should be considering cumulative impacts. The effects of this ruling remain to be seen, but it improves the DNR’s ability to manage groundwater and surface water resources while considering the interactions between the two.

Thus, the Little Plover River provides a powerful example of a case where a little bit of groundwater drawdown can lead to big environmental, political, and economic issues. Currently, hydrogeologists at the Wisconsin Geological Natural History Survey and USGS Wisconsin Water Science Center are working on developing a groundwater flow model of the region to help understand the impacts of groundwater withdrawals on the aquifer, and what that means for local surface water features like streams and lakes. Because the waters of the Central Sands are valued for many different uses, including farming, urban supply, and outdoor recreation, the team building this model has been working closely with different groups of users to determine the priorities and needs of the various water users the region, and make sure that their scientific tool they develop is both useful to and trusted by the decision-makers in the region. As the future of the Little Plover and other rivers unfold under increasing human pressures and climate change, it is critical that water scientists work together with the public to conduct fair and unbiased science that provides timely and useful information for the decision-making process.

When it snows, it pours (into aquifers)! Recharge seasonality around the world…

When it snows, it pours (into aquifers)! Recharge seasonality around the world…

Written by Scott Jasechko
University of Calgary
isohydro.ca
twitter.com/sjasechko


Groundwater is renewed by rain and melted snow that moves under the ground, a process called groundwater recharge. The percentages of summer versus winter precipitation that make it under the ground are expected to be different for a number of reasons including larger plant water use during the summer, and larger areas of frozen ground during the winter.
seasonal_recharge-01
Our recent research shows that winter precipitation is more likely to move under the ground than summer rain in many areas, including grasslands in Canada and the USA, deserts in Australia and Mexico, and valleys in China and Europe [Jasechko et al., 2014].

But most groundwater is managed over many years, not single seasons [Gleeson et al., 2010]. So who cares if recharge is biased to winter precipitation?

That groundwater recharge is biased to the wintertime matters because of ongoing and anticipated climate change. The warming world is changing how much precipitation falls during the winter and how much falls during the summer [Vera et al., 2006]. One implication of our work is that changes to winter precipitation are likely to have a disproportionately large impact on groundwater recharge compared to similar changes to summer rain.

Winter snow packs are declining in many cold areas [Hernández-Henríquez et al., 2015]. The impacts that declining snow packs and other changes brought on by global warming will have on groundwater recharge, remain unclear.


Most (70%) of this post is in plain language according to up-goer 5. Scott commented that he is much better at drawing snowflakes than he has ever been before thanks to https://www.youtube.com/watch?v=m9Ge-M5ljSI

Is research on ‘regional groundwater flow’ stagnant or still flowing?

Is research on ‘regional groundwater flow’ stagnant or still flowing?

brian at edmonton zoo Written by Brian Smerdon
IAH regional groundwater flow commission


toth unitbasin original

Scanned image of Joe’s original figure from the 60’s

In the early 1960’s József Tóth published seminal work on the concept of regional scale flow and nested flow systems. His work built on the “theory of groundwater motion” by M.K. Hubbard, and seemed to come along just at the right moment in history of hydrogeology. Armed with József Tóth’s work, the hydrogeologic community (geologist and engineers) began to see a picture larger than revealed by pumping tests, one that functionally related flow systems and natural processes and phenomena.

Over the past 50 years, the regional scale concept has certainly made a significant contribution to hydrogeology:

  • Nearly 1200 GoogleScholar citations
  • Special session at GSA’s annual meeting in 2007 (T34-1, T34-2)
  • Inverted imagery covering Freeze and Cherry’s textbook
  • Formation of the IAH Regional Groundwater Flow Commission (RGFC), whose mission is to foster international research and practical application of the concept through education and research activities, as well as organizing sessions at conferences.

However, one can wonder what the next ‘big step’ in regional flow might be. The list of peer-reviewed articles documenting regional flow evidence is gradually growing, but the basic understanding still links back to the seminal papers. What is the state of regional groundwater flow research? Did it reach maturity sometime in the past 50 years? How does it shape your current research?

To begin exploring the current state of regional flow research, a few discussions were initiated on the Regional Groundwater Flow Commission’s LinkedIn group page. Active supporters appear to have found use for the concept early in their careers, either in characterizing flow systems for better management of water resource, applying it to petroleum exploration, or simply as a basis frame their groundwater research of the moment.

When posed with the question about the future of regional scale research, many supporters shared the opinion that there is more scope for broadening the application across neighboring disciplines, rather than attempting to advance the underlying concept.

On LinkedIn, József Tóth summarized the discussion nicely:

“The regional flow concept has indeed matured in terms of understanding of the structure, effects and controlling factors of flow patterns. Major developments are unlikely to happen in the foreseeable future. However, I expect the concept to be extended by the broadening scope of its practical applications in the various groundwater dependent disciplines.”

Maybe the concept explains everything we can observe so far, such that there is no need for advancement. Maybe emerging methodologies and Earth observation technologies will lead to findings that can’t be explained by the regional flow concept. In this regard, regional groundwater flow research is in the midst of a period of ‘normal science‘, awaiting revolution.

So, perhaps the state of regional groundwater flow research is much like regional flow itself: parts of it are active/dynamic and interacting with other natural systems (i.e. educating the broader geoscience community, finding applications in other scientific disciplines); and parts of it are stagnant (i.e. the basic theory), awaiting for some transient signal to continue the evolution to a new equilibrium.

Let us know what your perspective is by commenting below!

Communicating research results through comics: is the permeability of crystalline rock in the shallow crust related to depth, lithology, or tectonic setting?

Communicating research results through comics: is the permeability of crystalline rock in the shallow crust related to depth, lithology, or tectonic setting?

Mark Ranjram, a Masters student in my research group, wrote a paper on crystalline permeability that is coming out in a special edition of Geofluids on ‘Crustal Permeability’ early in 2015 (other cool papers in early view here). Here is Mark’s awesome response when I asked him if he wanted to write a plain language summary:

PlainLanguagePermeabilityComic_1Column

1200 words to make sense of chaos: The Selker Scheme

1200 words to make sense of chaos: The Selker Scheme

This is an inspiring article by John Selker (Oregon State University) that was first published in the latest AGU Hydrology Section Newsletter (July 2014). John graciously offered to re-post it here… make sure you make it to his rules and a secret at the bottom.

Being elected a fellow of the AGU was an amazing honor, and I thank  those who so kindly nominated me, somehow crafting a silk purse from the assorted bits and pieces I have left behind over 25
years. I take this opportunity to address nontechnical aspects of my experience. After all, the science is easily found on-line, whereas the ins and outs of personal scientific strategy rarely see the light of day.

My research is the outcome of local optimization scheme with the objective of identifying the next approach when faced with calls for proposals which I saw I could address, thus seemed opportune, but did not deeply stimulate my curiosity. I was lured into that trap a few times. But in time, putting greater weight on “the likelihood that I will be excited by the work” than “the chances that the ideas will be successful” and putting “the chances that I would be funded” last,
my research program took a turn for the better (right around the time I got tenure – funny how that works). Behind this all lurks the fact that I am more fascinated by challenges than questions. I do
not see this as an advantage: great scientists seek answers to great questions, not just engaging puzzles. I tend to be hooked on a question, which sometimes take decades to unravel.

This “strategy” (more accurately a propensity) is best understood by an example of a question and its resolution. Here’s one which can be explained compactly, which we could call “the steam water
quality sampling conundrum:” design an ultra cheap sampler of 1-month time-averaged stream chemistry. What a neat problem! So we started with the fact that a sampler must have a vessel to
hold the material collected. Next, if it is to sample from a stream, it would be good if it sank. So at a minimum we must have a weighted brown glass bottle. At this point a little context is needed. David Rupp had just found significant pesticide in runoff and wondered how many stream might have this problem (Rupp et al., 2006), so we needed to sample at hundreds of points for the little money I
could gather: about $1,000 – the cost of the bottles. So we stared at a bottle: the answer must be here. “Fine, let’s just drill one tiny hole in the bottle cap and call it done.” When the stream water warms the
bottles air expands sending out 2% of the air from the hole (PV=nRT and T changes about 6 oK out of 300 oK). Cooling contracts the air, drawing in water. It fills half-way in a month. David and I had a great time making and testing these bottles. By the time we were confident in the design, the project was by over, but we got enough data to publish (Selker and Rupp, 2005). How important
was this work? The paper has been cited twice (and those only citing our work to justify that weird sampling strategies are publishable. A wonderful puzzle solved, but that interested fewer people than
would be invited to a dinner party.

So should we follow the branching Fibonaccian web of passion or a single path? Eternally seduced by the next “cool problem” means that I do not tend to follow otherwise discernible “lines of investigation” and is likely to lead to lost papers such as the sinking bubble bottle. I have been told that this is not the best route to “success,” and that staying focused on a single theme brings greater
recognition of your work. Yes, I agree, in the abstract. But this theory is trumped, in my opinion, by the absolute requirement that a researcher’s spirit be engaged in their work if they are to have a
hope of accomplishing anything truly original and important. If you don’t find yourself dreaming about it, you just aren’t fully engaged: you are just using a tiny fraction of your brain, missing out on
the chance to excel.

How do we balance these factors? Don Nielsen’s question needs to be added to the criteria for selecting a research project: is the problem important to humanity? And he means REALLY important!

Stumbling in the dark you are sometimes lucky enough to bump into a lump of gold. Marc Parlange is uniquely expert at helping people stumble productively. Preparing to come to Switzerland on sabbatical to work with Marc he suggested I work on glacier melting. The problem is that glaciers melt largely due to shortwave
radiation absorption, and if you stick anything in the glacier to measure the radiation or temperature, it gets hot in the sun, and melts the ice. “What if I had an entirely transparent thermometer?” I recalled hearing about fiber optic temperature measurements, so I started to check on that approach. We tried hard to measure the glaciers melt with fiber optic distributed temperature sensing (DTS), but the bottom line is that I never got any important publishable data. I tip my hat to all those studying snow! But the DTS method
allowed measurement of 10’s of thousands of temperatures across scales of 0.1 to 10,000 m. These are precisely the scales at which “point” measurements and remote sensing. This is an obvious gold mine for our science (opportune? Yes!). We have now used DTS to “see” air movement, quantify groundwater upwelling in streams, measure soil water content, observe lake stratification, surface temperatures of the ocean, and flow in deep boreholes. A wonderful aspect of the scientific endeavor is that we move as a community. We (my DTS buddies Scott Tyler and Nick van de Giesen) have now put on 15 hands-on workshops training folks how to use the method, and started an NSF-funded center (CTEMPs.org) where we make the gear and technical support available to others who have ideas that DTS might help address. It has been a delight.

The bottom line is that life is too short to:
1. Study problems that don’t matter;
2. Try to “go it alone” rather than feeling the joy of community;
3. Get stale studying the same old thing. If you feel it is fresh, great. If not, then open your eyes to new problems;
4. Worry about others stealing your ideas!The jokes on them – you are multiplying the number of people who are helping you answer the questions that you can’t wait to understand. Share your ideas, your data, your time.

Here’s a little secret: the coolest problem ever is just around the bend. Take the corner, and enjoy the ride. I can’t point the way, but following a few simple rules I promise you’ll have a great time
wandering.

Rupp, D.E., K. Warren, E. Peachy and J.S. Selker. Diuron in Surface Runoff and Tile Drainage from Two Grass-Seed Fields. J. Env. Qual. 35:303-311. 2006.
Selker, J.S. and D.E. Rupp. An environmentally driven time  integrating water sampler. Water Resour. Res. 41. W09201,DOI:10.1029/2005WR004040. 2005.

The home of our hearts day 5: The Sydney Tar Ponds and keeping the spark alive

[part six of a special six-part blog series by Mark Ranjram, MEng student at McGill University. From June 8 to June 13 2014, Mark had the privilege of being a part of the Canadian Water Network’s (CWN) Student and Young Professionals (SYP) Workshop in Cape Breton Island, Nova Scotia. Here is the prologue to this series.]

The fifth and final day of the workshop started off with a tour of the Sydney Tar Ponds. The tar ponds are a massive contaminated site originating from the production of coke (a derivative of coal), a popular fuel used by the steel plants in Cape Breton to heat their furnaces. A large remediation effort is being conducted at the tar ponds, with 700,000 metric tonnes of contaminated sediment being trapped over a 31 hectare area.

From the tar ponds, we went on a walking tour of a neighbourhood in Sydney immediately adjacent to the now defunct steel manufacturing plant. Our tour guide gave us the history of the neighbourhood, explaining the deeply discriminatory, destitute conditions the workers lived and worked in; similar in many ways to the plight of the coal miners which we explored in Day 3. One of the most haunting things our tour guide showed us was the tunnels which acted as gates into the steel plant compound. As workers walked through these gates, we were told to imagine the blast of heat and dust they would experience as their long day at the plants began. The tour was yet another remarkable realization of the true difficulty people face in their lives, and the amazing ability for the islanders of Cape Breton to overcome these challenges and maintain an optimistic, innovative perspective.

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Tunnel into Sydney Steel Compound. Photo Credit: Mark Ranjram

The day ended with a “kitchen party” at a local restaurant, where we sat at a long table and closed off our week in style. At the end of the night, we completed a final talking circle where we talked about what we gained from the workshop and how we aimed to pay it forward. Again, the circle was emotional, vulnerable, hilarious, and heartwarming. As we went around the circle I was again taken aback by how terrific the entire group was and what great things we could achieve with our entire careers ahead of us; and what could be accomplished by all the other people that weren’t there but have that same fire and that same genuine commitment to making the world even just a hair better than it was when they got here. I made a pledge at that table to find a way to bring some environmental education to my community, for example, helping people in my community understand where their water comes from, where it goes, what climate change is and its consequences, and other things in that vein. If I can bring even a modicum of environmental baseline knowledge to the people in my neighbourhood, I will have made a small contribution towards helping create a sustainability-knowledgeable citizen base and voting public. I’m not sure how I will accomplish what I want to accomplish, but the first nations and non-indigenous people of Cape Breton, our amazing workshop leaders, and the nineteen young researchers and professionals I met at the workshop will forever motivate me to make a positive mark on the world. There is a rising tide in the coming generations of water leaders, and I certainly refuse to be left behind as all these brilliant, committed people spend their time making a difference! Thank you again to everyone involved in the workshop, and thanks to all the people out there who want to see a sustainable world and believe it is possible in spite of all the great challenges we face today on Earth socially, politically, economically, and environmentally.

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#CWNSYP Cape Breton! Photo Credit: Liana Kreamer

The home of our hearts day 4: the water-energy nexus & deep thoughts on salty water

[part five of a special six-part blog series by Mark Ranjram, MEng student at McGill University. From June 8 to June 13 2014, Mark had the privilege of being a part of the Canadian Water Network’s (CWN) Student and Young Professionals (SYP) Workshop in Cape Breton Island, Nova Scotia. Here is the prologue to this series.]

The focus of the fourth day of the workshop was the relationship between energy and water. Cape Breton, with its long history of coal extraction and its proximity to water, was a great place to explore this relationship first hand. We started our day at a community sports complex in Glace Bay, where a shallow flooded mine is being used to store and generate geothermal energy. This was yet another example of the terrific power of the local Cape Breton communities to generate innovative adaptations using their deep understanding of their environment and local issues.

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Geothermal energy at the BayPlex sports complex in Glace Bay. Photo Credit: Shao Hui

From the sports complex, we travelled to the Point Aconi Fire Generating Station, a coal-fuelled power plant. The facility was incredibly massive, and during our tour we stood next to the giant sweltering furnace that burns the coal and looked down the maw of a 300 metre sloping coal conveyor belt, both sights a stark visual reminder of our species’ ability to bend the environment on incredible scales.

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Looking down a coal conveyor tunnel at the Point Aconi Fire Generating Station. Photo Credit: Mark Ranjram

From the power plant, we headed to the Great Bras d’Or Channel, which connects the Bras d’Or Lakes (actually a marine estuary) to the Atlantic Ocean. Here we discussed the potential and challenges of tidal energy production from the large tides which pulse through the channel.

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Dr. Bruce Hatcher explaining the feasibility of tidal energy in the Great Bras d’Or Channel. Photo credit: Kristen Leal

With the technical side of the day done, we proceeded to Baddeck, a small tourist down adjacent to Alexander Graham Bell’s family estate, for a sailing experience on a real sailing ship. As the cold Atlantic breeze whipped past us, we pointed out jellyfish in the water and eagles in the sky and I could not help but think about the deep connections between water and energy in Canada. What are the mechanisms by which we can take our role as stewards of our environment and balance that with our role as supporters of our families and communities; both being of critical importance to our species’ endeavour on this planet? The Mi’kmaq first nations on the island have an incredible commitment to both their environment and their communal economic success, and the non-indigenous population on the island has shown awesome commitment to sustainability and remediation, but how can we get that perspective to scale up to a population as large and as varied as our entire country? Thinking about Toronto, my hometown of roughly 2.5 million people, where green spaces are relatively plentiful for a city but are not necessarily part of our day-to-day, where the rivers are small and hidden away, and the lake is so large as to suggest infinite abundance, how do we develop that baseline of environmental understanding? And how do we translate that understanding amongst a finely discretized gradient of cultural, social, and economic motivations? The answers to these questions are not straight forward, but sometimes the most important step is to just open the sails and give yourself a chance to catch the wind.

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They even let me sail the boat! Photo Credit: Raea Gooding

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