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Urban water underground: How green infrastructure makes it visible

Urban water underground: How green infrastructure makes it visible

Post by Theodore Lim, assistant professor of Urban Affairs and Planning at Virginia Tech. He researches the socio-hydrology of green infrastructure planning and implementation.


In order for people to care about something, to value it, they have to be able to see it and experience it. This point should not be taken lightly. So much about decision-making and policy-making depends on how much public support can be organized around any given issue. So, when it comes to protecting the water resources that sustain society and the natural environment, it is perhaps unsurprising that groundwater is the part of water cycle that most folks tend to ignore.

Historically, urbanization has made it difficult for residents to experience key parts of the water cycle. In Philadelphia, for example, in order to improve sanitation, reduce flooding, and make way for the regular street grid, dozens of streams were channeled into brick sewers that were then buried under roads to make transportation routes more efficient and the city easier to navigate. Today, these historical streams are literally buried underground, and still carry a mix of raw sewage and stormwater runoff, that overflows into neighboring creeks and streams when it rains.

Sewering Mill Creek in West Philadelphia, 1883. Image Source: http://www.phillyh2o.org.

Green infrastructure is an approach to urban water management that reintroduces key parts of the hydrological cycle to the visible urban environment. Green infrastructure can involve surface water, through daylighting streams, but it can also means removing concrete and asphalt, to allow water to trickle slowly into the ground, be soaked up by plant roots, and evaporated back into the air, or to recharge deeper groundwater tables. An example of this is a rain garden, or bioinfiltration facility, which intercepts rainfall with vegetated land, as an aesthetic and low-maintenance alternative to conventional drainage systems.

Bioinfiltration facility installed in a residential neighborhood in Washington, D.C. (Photo by author)

How do urban residents “see” these important elements of the hydrological cycle? One answer is: by their recognizing them as “infrastructures” for modern cities — elements that provide critical services, in addition to environmental amenities. Plants and restored soils are not just “nice to have,” they help moderate surface temperatures, protect water quality, and support biological function. Public investment in street tree planting has been shown to increase pedestrian activity, public health, and property values. Green infrastructure programs in cities can also be integrated with climate action plans, sustainability initiatives, and parks and recreation programs; such programs often attract businesses and residents with their progressive attitudes.

Urban residents can learn about the “ecosystem services” associated with hydrological cycle improvements thanks to scientific signage, infographics, partnerships between  environmental non-profits and community outreach, programs run by municipal water managers (water/wastewater utilities, departments of environmental protection, or stormwater districts). Most of all, residents learn from each other and are more likely to adopt environmentally friendly behaviors when they are surrounded to neighbors who do the same.

Stormdrain art in Philadelphia, designed by children in Philadelphia public schools (Photo by author)

Green infrastructure monitoring and signage in Chicago. Image: https://nextcity.org/daily/entry/chicago-sensors-green-infrastructure-study

Restoring hydrological function within urban areas can be seen as a microcosm of larger-scale environmental policy-making. On the regional scale, “green infrastructure” can refer to the large swaths of undeveloped land in a natural state, or to working lands, such as those used for timber production or agriculture, which all provide critical ecosystem services to society. Environmental planners who work at the state or regional level or with land trust organizations, might use policies, economic incentives, and land regulations to protect these landscapes from low density suburban sprawl or urbanization. However, on both urban and regional scales, the decision-making about land use, management, and development is heavily dependent on co-operation between diverse stakeholders, and relies on a mutual understanding of the value of natural environments for various communities..

Urban and environmental planners tell stories that bring together multiple voices in collaboration.  These stories also give the historical and social context to decision-making around environmental systems, which is vital to ensure equitable outcomes. Unfortunately, despite advances in integrated modeling and the scientific knowledge of complex interrelations between water and society, decision-making still falls back on heuristics and rules-of-thumb. A highly relevant question therefore is: how can we integrate groundwater science into more robust city and regional-scale participatory planning, that is equitable and implementable? The answer will hopefully lead us to a strategy where urban and environmental infrastructures visibly advance the well-being of communities.

Socio-hydrology meets Broadway: Can we survive drought if we stop using the toilet?

Socio-hydrology meets Broadway: Can we survive drought if we stop using the toilet?

Post by Samuel Zipper, postdoctoral fellow at both McGill University and the University of Victoria, in Canada. You can follow Sam on Twitter at @ZipperSam.

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How can society best cope with water scarcity?

With Cape Town on the verge of being the first major city to run out of water (a topic for a future post here on Water Underground), this is a question on the minds of many water managers and scientists within the emerging fields of socio-hydrology and socio-hydrogeology.

Low levels in Cape Town, South Africa’s reservoir system. Image source: University of Cape Town News.

Recently, my wife & I had the opportunity to see a more musical exploration of this question at the Langham Court Theatre’s production of Urinetown here in Victoria. This satirical musical envisions a future in which severe droughts have limited water supplies to the point that government (controlled by a corporation) decides the best way to conserve water is to charge people to use the restroom, thus limiting both direct and indirect human consumption (by people drinking less and flushing the toilet less, respectively).

As a scientist, I naturally found myself wondering: how effective would this tactic be?

Fortunately, the data exist to give us at least a rough approximation. Globally, only about 10% of water is used in households; the vast majority (about 70%) goes to agriculture. Once the water reaches your household, however, Urinetown may have a point; in an average US household, toilets are the largest water user, averaging ~1/4 of domestic water use (33 gallons per household per day). Since the US has among the largest per-capita water use of any country, we can use this number as an upper bound for a back-of-envelope calculations: globally, if we collectively stopped flushing toilets today, we’d reduce water use by a maximum of 2.5%.

In contrast, switching to diets with less animal protein (particularly beef) can have a far greater impact, saving well over 10% – it takes 660 gallons of water to make a burger, equivalent to about 180 flushes of a standard toilet (see the water footprint of various foods here). However, water is inherently a local issue – most of the water that goes into your burger was used to grow crops, potentially far away from wherever you live, and does not consume local water resources. Also, the numbers we used for the above calculations have a lot of local variability, with up to ~1/3 of total water use in Europe and Central Asia in the household.

Percentage of indoor water use by different fixtures. Source: Water Research Foundation.

So overall, does the math add up for Urinetown? At a global scale, reducing agricultural water use through improvement in irrigation practices and changes in diet is going to have a much bigger impact. Locally, however, toilets do use a lot of water and restricting their use during times of crisis is a smart approach – and Cape Town has had an “If it’s yellow, let it mellow” recommendation since September. Replacing your toilet with a high-efficiency fixture can help as well – many cities and states have rebate programs to help reduce the costs of this switch.

And how does it turn out for the residents of Urinetown? To answer that question, you’ll have to see the show yourself. Urinetown had a three year run on Broadway, including winning three Tony Awards, and is now a popular choice for theatres all around the world.

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Sam Zipper is an ecohydrologist. His main research focuses broadly on interactions between vegetation and the water cycle, with a particular interest in unintended or indirect impacts of land use change on ecosystems resulting from altered surface and subsurface hydrological flowpaths. You can find out more about Sam by going to his webpage at: samzipper.weebly.com.

Happy birthday plate tectonics!

Happy birthday plate tectonics!

Post by Elco Luijendijk, a junior lecturer, and David Hindle, lecturer and head of geodynamic modelling, both at the Department of Structural Geology and Geodynamics at the University of Göttingen, in Germany.

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As we’ve firmly moved into 2018, we can say happy 50th birthday to one of the most revolutionary scientific theories of the last century: plate tectonics. Here we discuss the birth of plate tectonics and what it means for hydrogeology.

Plate tectonic theory explains the how the Earth’s surface is formed and how it consists of rigid plates on top of a layer that is called the asthenosphere and that behaves like a slow-moving liquid. The plates move around, collide and subduct beneath each other. Plate tectonics successfully explains many features of the surface of the Earth, such as mountain belts at the collision zones of plates, ocean basins at places where plates move apart and the concentration of earthquakes near plate boundaries. For instance it is quite easy to recognize the boundaries of tectonic plates if you look at the earthquake distribution in Figure 2.

Plate tectonics birthday cake, showing one tasty tectonic plate (left) subducting below another (right). Source: http://sara-geologicventures.blogspot.de/2012/05/cake-subduction-zone.html

Actually, depending on your definition either 2017 or 2018 is the 50th birthday of plate tectonics. The story why this is the case is a bit complex. Jason Morgan first presented the theory at meeting of the American Geophysical Union (AGU) in 1967. However, the first paper on the mathematical principle of the movement of tectonic plates was published in the same year by McKenzie and Parker (1967). Jason Morgan’s paper (Morgan 1968) is the first one to clearly demonstrate the global geometry of all the major tectonic plates, but had got delayed by peer-review for over a year. The development of plate tectonics involved many scientist and several earlier theories, such as seafloor spreading (which showed that ocean basins were split in two halves that were moving apart). There are surprisingly few books available on the history of plate tectonics, but one that is definitely an enjoyable read is “Plate Tectonics: An Insider’s History Of The Modern Theory Of The Earth” (Oreskes 2003). It is a fascinating collection of stories by most of the scientist that were involved in the development of the theory.

Figure 2 Plate boundaries on earth, with earthquakes > M6.5, since the year 2000, and with selected relative motion arrows for plate pairs – the motions shown are always those between adjacent plates. Double arrows imply spreading – moving apart of plates, mostly on oceanic ridges, while single arrows imply either strike slip motion (California and the San Andreas fault for instance) or convergence (either subduction of an oceanic plate under a continental one – under the Andes mountains in South America as an example, or collision of two continental plates as between India and Eurasia in the Himalayas for instance). Earthquakes are clearly concentrated on plate boundaries. This map was made using GMT (http://gmt.soest.hawaii.edu/).

Ok, that is all very interesting, but you could ask the question: what does plate tectonics have to do with Water Underground?

In some regards not much. We can often ignore plate tectonics when looking at groundwater flow. Hydrogeologists tend to study groundwater supply and pollution on human time and space scales. Because plates move very slowly (up to tens of mm per year), on short timescales the subsurface can be regarded as static layer of rocks that does not move or deform. However, most of the groundwater on our planet is old, and has infiltrated to the subsurface ten thousand years ago or earlier (Jasechko et al. 2017). The oldest groundwater that we know is 1.5 billion years old and was found at 2 km depth in a mine in near Timmins, Canada (Holland et al. 2013). Over its long history it was part of ancient and long disintegrated continents and the plate that holds this water moved from an area south of the equator to its present position.

Plate tectonics affect groundwater. Especially in deeper (several kilometers) parts of the crust, the groundwater pressure, salinity and composition that we encounter today are often the result of a long geological history. Over time, sediments were added and removed by erosion, layers were compacted, folded and/or faulted, which affected groundwater flow and its interaction with the rocks that contain it.

The reverse is also true: groundwater affects plate tectonics. This is perhaps most important near mid-ocean ridges, where two plates move apart, and new crust is being added to these plates all the time. There is abundant evidence for strong circulation of seawater through the subsurface, which cools the hot new crust, reacts with the rocks around it and changes the chemistry of the crust and the ocean. The most visible evidence are so-called black smokers (Figure 3), where hot (350 ˚C) water discharges into the ocean through fissures in the crust and carries along black plumes full of dissolved minerals. At the opposite end of the plates, the presence of water underground changes how easy or hard it is for one plate to subduct beneath another in a plate collision zone, as was discussed at a recent AGU conference (link to session), 50 years after the AGU conference where Jason Morgan presented his theory. On a smaller scale, faults that enable the stacking of rocks in plate collision zones (mountain belts) or the breaking apart of rocks in rift zones (where plates split up), are dependent on the presence of groundwater. Even before the advent of plate tectonics Hubbert and Rubey (1959), showed that water in fault zones can act as a kind of lubricant that enables two adjacent blocks of rocks to move past each other. Because this movement gives rise to earthquakes, groundwater may also play an important role in the earthquake cycle. This role is still heavily debated and is researched by drilling deep wells in faults at plate boundaries, such as at the San Andreas fault in California (Zoback et al. 2010) or the Nankai through (Hammerschmidt et al. 2013).

Without sufficient groundwater plate tectonics may not exist on our planet. The movement of tectonic plates depends on how easily the rocks below these plates can deform. At these depths, high pressures and temperatures promote the slow deformation of the crystals that make up the rocks at this depth. The mechanisms that cause the deformation of crystals are termed “creep”. Whether or not the rock contains water (in the form of -OH groups) affects creep: generally, “wet” minerals are up to a factor of 10 “softer” than “dry” ones. The actual physics and chemistry of how -OH affects and weakens different minerals is not entirely clear. Creep is also essential for the convection of the earth’s mantle, which controls the escape of heat from our planet’s interior and provides the energy to drive plate tectonics. Without convection, there would be no plate tectonics, so the presence of water throughout the earth’s crust, and its continued reintroduction to the earth’s mantle by the subduction of tectonic plates seems to be a key component driving the system, or at least, helping it to keep moving along.

There are many more links between groundwater and geologic processes, too many to cover in a short blog item like this. However, the current state of our understanding is summarized in a highly recommended book “Groundwater in geologic processes”. Many aspects of groundwater flow and its links with geological processes in newly formed, colliding or subducting plates are still uncertain and studied by hydrogeologists, which means that 50 years after the publication of the theory of plate tectonics, many discoveries still lie ahead.

Figure 3 A black smoker at the mid Atlantic ridge emitting hot groundwater into the ocean from newly formed oceanic crust. Copyright: MARUM – Center for Marine Environmental Sciences, University of Bremen.

Links:

1: McKenzie and Parker (1967) https://www.nature.com/articles/2161276a0

2: Morgan (1968): http://onlinelibrary.wiley.com/doi/10.1029/JB073i006p01959/full

3: Oreskes (2003): https://www.routledge.com/Plate-Tectonics-An-Insiders-History-Of-The-Modern-Theory-Of-The-Earth/Oreskes/p/book/9780813341323

4: Jassechko et al. (2017): https://www.nature.com/articles/ngeo2943

5: AGU fall meeting session (2017): http://agu.confex.com/agu/fm17/meetingapp.cgi/Session/31184

6: Hubbert and Rubery (1959): https://pubs.geoscienceworld.org/gsabulletin/article-lookup/70/2/115

7: Zoback et al. (2010): http://onlinelibrary.wiley.com/doi/10.1029/2010EO220001/full

8: Hammerschmidt et al. (2013): https://www.sciencedirect.com/science/article/pii/S004019511300098X

9: Ingebritsen et al. (2006) Groundwater in geologic processes. http://www.cambridge.org/de/academic/subjects/earth-and-environmental-science/hydrology-hydrogeology-and-water-resources/groundwater-geologic-processes-2nd-edition?format=PB&isbn=9780521603218#RcR6adP330ESbBPk.97

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David Hindle (L) is a lecturer and the head of geodynamic modelling in the Department of Structural Geology and Geodynamics at the University of Göttingen, and Elco Luijendijk (R) is a junior lecturer also in the Department of Structural Geology and Geodynamics at the University of Göttingen.

A cool new collectible: Water

A cool new collectible: Water

Post by Matt Herod, Waste and Decommissioning Project Officer for the Canadian Nuclear Safety Commission, and Adjunct Professor in Earth and Environmental Science at the University of Ottawa, in Ottawa, Canada.

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I have always been a mineral and fossil collector. It was a hobby that stuck and blossomed into a career. I still collect minerals and fossils, although I’ve now added rocks from my field sites to the collection. One thing I should note is that for inanimate, immobile objects it is shocking how quickly rocks can colonize parts of a house, garage, basement, etc.

However, since my early years in geology a very large part of my day is concerned with water; my PhD was almost exclusively about water. Water is my focus and it is truly fascinating. So that got me thinking. Why don’t I collect water?

You may think water is all the same. Turn on the tap, it comes out, drink, wash, whatever. It’s just water. Well, you could not be more wrong. Water is different and changeable. Plus it fits in a small bottle. In short, the perfect collectible.

But maybe you’re not convinced to start collecting water just yet.

Water has types, an identity, just like people. You may be familiar with the notion of people’s personalities being Type A’s, B’s and C’s. Although the types of water are a little more nuanced. That said, so are the types of people.

Water is sorted into types based on its chemistry. The chemistry of water comes from the dissolved salts within it and the relative concentrations of those salts. The isotopic composition of water can also be used to identify its type. Some water types are classed based on their heritage. For example, water found in pore spaces deep underground is often called brine, the precursor to that brine is, or often was ancient ocean water.

Let me give you some examples of water with interesting identities. One thing I should mention is that many of the ways waters are typified only consider their dissolved salt concentration, however, when you factor pH, Eh, and isotopic variation of the many, many different isotopes the number of water types balloons exponentially. For example, a water with a pH of 6 and a total dissolved solids (TDS) concentration of 500 ppm can have isotopic ratios, age and origin totally different from another water with the same pH and TDS. Like I said, it gets complicated fast.

To start with an easy one:

Seawater: Not only is it familiar, it is pretty important given that 97% of Earth’s water is this type and a significant percentage of Earth’s biomass lives in it. Seawater is about 3.5% saline and one of the most interesting features of the water is that it is pretty much everywhere and chemically very consistent. There are differences in the composition of seawater in the certain places around the world, for example, in restricted basins salinity can be higher or where fresh water enters the ocean in a river delta or estuary salinity is lower. Isotopically seawater is also interesting. Not because it has an unusual isotopic composition, but because seawater has been set as the standard to which all other water is compared. It is the zero point that stable isotopes in all other water is measured against.

Glacial Water: Of the 3% of Earth’s water left after the oceans, 69% is frozen in glaciers. To condense the characteristics of glacial water into one word I’d say clean. It just doesn’t have much in it. The reason for this is that glacial water started its days as precipitation, which is water that was evaporated from a water body and condensed. The evaporation process removes almost all of the dissolved solutes. Therefore, there just isn’t much stuff in glacial water besides the H and the O. That doesn’t mean glacial water is boring though. There is still a lot that if can tell us. For example, the variations in O isotopes can be used to reconstruct past temperatures and gases trapped in the ice can tell us about the composition of past atmospheres as well. The information we get from glacial water is different, but extremely valuable!

Brine: Do not drink a brine. You WILL regret it. I do not speak from experience, but frankly if almost 30% of the fluid is salt, it simply isn’t drinkable. Brines come in a lot of flavours, and technically if it has >5% salt it’s considered brine. However, I have encountered some brines that are over 30% saline. Of course, they were not drinkable as they were porewater in a sedimentary basin. However, there are some extremely salty bodies of water out there as well. Brines are interesting because they have so many stories to tell. There is history there, recorded by the solutes, gases and isotopic composition of the brine that explains how it became more than a simple water and transcended the label of water entirely to become much, much more…a fluid. Typically brines in nature have a history that involves salt dissolution leading to high concentrations of Na and Cl. However, other types may simply be evaporated seawater causing all of the dissolved ions to become more concentrated. For example, brines often have high concentrations of Ca, Br, I, Sr, etc, etc. Isotopes in brines also reveal a lot about their past and can distinguish if a brine is a glacial water that has dissolved salt, or is evaporated seawater or has a hydrothermal component. There is just always more that you can find out about brines.

High and low pH waters: pH plays a huge role in dictating the chemistry of water and the dissolved salts therein. Around the world there are naturally occurring waters that have incredibly high and low pH’s. The low pH waters, typically around 1-3 on the pH scale, occur in areas where natural acid rock drainage is happening. Acid rock drainage, aka. ARD, happens when sulphide minerals, often pyrite, oxidize releasing sulphuric acid leading to seeps with exceedingly low pH’s. On the other hand, high pH waters occur more rarely. Alkali springs occur when water comes in contact with hydroxide minerals, such as calcium hydroxide. Hydroxides form in dry, arid environments or where organics and limestone have been heated and burned such as areas with volcanic activity. One famous alkali spring is the Maqarin site in Jordan where water with pH’s from 11-13 occur!

Hydrothermal waters: HOT, HOT, HOT! These waters are absolutely loaded with interesting chemistry. Spewing out of hydrothermal vents on the seafloor at temperatures of up to hundreds of degrees Celsius with tons and tons of dissolved metals like copper, lead, gold, zinc, silver, etc. Furthermore, many of the world’s metal deposits are related to the movement of hydrothermal fluids within the crust. Hydrothermal fluids get their heat from the mantle or magma chambers within the crust. As they are heated they dissolve the rocks in contact with then leading to highly enriched solute concentrations and then when they discharge and cool, the solutes precipitate leading to black smokers, or mineral precipitates in fractures in the crust.

Young and old waters: My last Water Underground post discussed this in more detail. Suffice it to say when you start analyzing carbon-14, tritium, chlorine-36, iodine-129, krypton-85 and 81, etc. you can find waters ranging in age from just a few years to tens of millions to billions of years old. Each of these, is worthy of a spot on my shelf that is for sure. Excitingly, each of these waters has a story to tell about its origin and experiences over the years. Analyzing these isotopes and putting them in context with the geologic history of where the water is found can explain a lot about the regional hydrologic cycle and how water recharges, and discharges and how vulnerable the aquifer it is housed in is to contamination or over-pumping.

This is just the tip of the iceberg (see above). There are many ways water is sorted into types, often called “facies”, which are then plotted graphically. Here is a nice paper that compares some of the different ways of plotting water [1]. Read all the way to the end an you’ll be rewarded with a somewhat strange smiling face.

Anyway, hopefully I’ve convinced you to grab a bottle and collect a sample or two when you come across an interesting water!

Finally, my only piece of advice if you’re going to start a water collection…make sure the top is screwed on tight.

Reference

[1] Güler, Cüneyt, et al. “Evaluation of graphical and multivariate statistical methods for classification of water chemistry data.” Hydrogeology journal 10.4 (2002): 455-474.

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Matt Herod is a Waste and Decommissioning Project Officer for the Canadian Nuclear Safety Commission, and an Adjunct Professor in Earth and Environmental Science at the University of Ottawa, in Ottawa, Canada. To keep up to date with Matt, follow him on Twitter or on his own EGU blog GeoSphere!

An alternate career path for Groundwater Science-Engineering PhDs

An alternate career path for Groundwater Science-Engineering PhDs

Post by Jim Roy, Research Scientist at Environment and Climate Change Canada.

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A recent editorial in Nature highlighted the relative scarcity of academic positions available to graduating PhD students (Many junior scientists need to take a hard look at their job prospects; 25 October, 2017). It notes that “it has been evident for years that international science is training many more PhD students than the academic system can support”. Firm figures aren’t available, but the article suggests maybe < 5 % will land a full-time academic job. That number may be somewhat higher for Groundwater-related disciplines, but the point remains that many should “make plans for a life outside academic science.”

However, it’s not all doom and gloom; indeed the article goes on to state that “it is good for PhD students and postdocs to pursue careers outside academia. Many will find similar challenges and rewards in industry.” There are a lot of options for Groundwater PhDs in industry and the plethora of supporting consulting firms: in mining, oil and gas, tunnel and dam engineering, municipal water supply, and contaminated site remediation, to list a few. However, there is an additional career path to consider, especially if you want to continue doing research – the government scientist, like me.

According to Wikipedea: A government scientist is a “scientist employed by a country’s government, either in a research-driven job (for example J. Robert Oppenheimer on the Manhattan Project), or for another role that requires scientific training and methods.” I’ll be focusing on those that do research (encompassing science and engineering), at least for much of their work.  And in this blog, I’ll be comparing their job duties and conditions to that of the professor, the research job with which the majority of students and post-docs are most familiar and traditionally aiming for.  It’s what I thought I would be too, coming out of grad school. Now it’s been 10 years since I took up my position as a Research Scientist focusing on groundwater contamination/quality with Environment Canada (now Environment and Climate Change Canada) – enough time to have experienced the ups and downs of the Canadian economy and the changing of the governing party, with repercussions of both for federal science priorities and budgets. The discussion below is based largely on my own experience, with insight gleaned from talking with colleagues in other government agenciesa over the years. It’s also highly generalized; the exact situations will vary by country, agency, and even by individual scientist, and may change over time. But hopefully it’s good enough for a light-hearted introduction to this alternate career area.

So here goes – my Top 10 list of how a government scientist job is different than academia:

  1. Freedom

                All scientists want to do work that is meaningful, but not all scientists get to choose on what topic that work will focus. In general, government scientists undertake research on issues of government priority that will advise on federal policy, regulations, and management activities, or that will provide service to important national industries or the public. So their work should have a meaningful impact on their country, if not more broadly; they just don’t get to decide on the priority topics (with exceptions for certain agencies or programs). However, often these priority topics are general enough that there is some range of projects that can fit within them, giving the scientist some flexibility on their research focus. Also, by advising their management and government representatives of important topics, government scientists may influence the direction of government priorities. Also, a government scientist may be afforded some leeway to work on additional topics outside these priority areas with a small fraction of their time. Government research usually targets short- to intermediate-term achievements, as fits the common government election cycle. However, some priority topics may last for decades – see North American Great Lakes eutrophication and algal blooms – waxing and waning in importance with the severity of the problem (costs!) in relation to the other pressures on the government (the economy!). For those who choose this career path – beware, though, when government priorities change, your research area may have to change too.

                For academics, their options are typically much broader, encompassing everything between applied research with immediate implications to research so basic that nobody can predict what may eventually come of it. The caveat to this is that an academic’s research topic often has to be deemed important enough and applied enough for “someone” to fund it. Industry funding is usually quite applied. But even government funding agencies, which are usually the primary support for more basic academic research, are increasingly imposing greater direction over the acceptable topics of proposed research. So perhaps this extra freedom isn’t so vast in practice.

  1. Trading places?

                Many government scientists are appointed to one or more adjunct professor positions at universities where their academic collaborators reside. These could be at nearby universities or those across the globe, and these locations may change over a career. It isn’t a paid position, but allows for closer research ties, including the (co-)supervision of undergraduate and graduate students, which benefits both the university and the government agency. Such positions may also afford access to laboratory space on campus or to additional research funding (held at the university, but directed by the adjunct professor).

                I haven’t heard of a case of the opposite arrangement – adjunct government scientist – but it might exist. Academics may pop in and be given some office space and support during a sabbatical while collaborating with a government scientist, but they’re really just temporary squatters.  If anyone out there knows of such a situation, feel free to post below.

  1. No teaching ( 🙂 or  🙁 )

                An obvious difference, this can be viewed as good or bad news depending on how much you like it.  I enjoyed teaching while I was a grad student. Many scientists give guest lectures or even short-courses at local universities. I taught an entire hydrogeology course for a university colleague during his sabbatical – so this can be an option for some in government who have an interest. Not having required teaching does provide greater flexibility in scheduling your work (especially field trips) and leaves more time for research and/or other important activities, like playing hockey or “family life”.

  1. Professors have grad students; government scientists have technicians

                The model for academic research is based on students and post-docs (a team of them often) carrying out the primary duties of research under the supervision of their professor. Certainly there are exceptions where the professor carries out their own study, but generally they lack the time for this. However, professors may have technicians too. It’s common for some to hire current or past students as technicians for a few years after they graduate, while (senior) professors may have dedicated technicians.

                In contrast, the model for government scientists is to have one or more dedicated and highly-experienced technicians available to assist in their research. Separate analytical laboratory or field teams may also be available. Although, with tightening budgets this technical support seems to be dwindling. It’s also fairly common for post-doctoral fellows to be hired by government agencies to work with their scientists – I’ve worked closely with 2 post-docs over my 10 years at Environment and Climate Change Canada. And what’s more, through adjunct professor positions or just collaborations, government scientists may also work with and (co-)supervise students from a partner university, just not to the same extent as for the academics.

                Thus, there can be a fair bit of overlap between these two models, especially when collaborations extend between academics and government researchers; and this integration, I think, makes for better science all around.

  1. Both are sought out by regulators and policy-makers

                Government scientists might have the inside track to the ear of policy-makers, but advice from academics is often gathered via workshops and contracts for reviews and reports as well.  Sadly, in large departments especially, some bureaucrats may not realize they have internal expertise in an area like hydrogeology. Which leads us to the next point…

  1. Governments typically do a poorer job of selling/showcasing their scientists

                Academics have much more freedom to showcase themselves and their work to the public, the science community, and business/industry. This can be through personalized research web pages, starting a blog (like this one!), and greater freedom to speak to the media (depending on the presiding-government’s rules for their scientists).  They also tend to attend more scientific conferences, where they and their students can advertise their scientific wares to a range of audiences.

  1. No consulting on the side

                Not all professors consult, but many do, which can provide a boost in income and lead to funding or in-kind support opportunities for their research or to job opportunities for their students. I haven’t heard of any government agencies that allow their scientists to consult as a side profession. In part, they want all your time devoted to your job working for them; but it also runs into “conflict-of-interest” concerns.  Now that doesn’t mean you can’t have a side-job (e.g., selling pottery, repairing dishwashers, stand-up comedy, teaching Yoga), but it can’t relate to your science profession.

  1. Border-crossing restrictions

                Working on national (or state/provincial) priority research commonly means government scientists work predominantly on sites in their own country (region), unless inter-jurisdictional agreements are made to combine or share research expertise. In contrast, academics are able and encouraged to work at international sites, which can expand the range of research topics and potentially funding sources available to them.

  1. Less competition for funding (except when the coffers are bare)

                Much of my funding is internal, requiring much shorter (i.e., less onerous) proposals than is typical for my academic colleagues seeking funding through centralized national funding agencies (e.g., NSERC in Canada) or from industry partners. My proposals may still go through a competitive process, though, sometimes with external reviews.  How substantive this internal funding is compared to academic funding will depend on the agency, how science is viewed by the current government, the state of the economy, and the importance of the topic. When internal research budgets are tight, there may not be sufficient funding to go around, especially for those not working directly on key priorities. Of note, some government agencies allow their scientists who have adjunct status at a university to apply for the same set of grants as academics. Whether such proposals are frowned upon or judged differently by funding agencies is up for debate.

  1. Joy in their work

                Frustrations with too-much time devoted to administrative tasks and seeking funding are prevalent in both government and academic research areas. But still, the opportunity to do research on interesting, challenging, and important topics at the edge of our current scientific understanding brings enjoyment / fulfillment to both government scientists and academics. We all feel that slight quickening of the pulse when “the data is in” and we learn if the expected outcomes were realized or (better yet) something different (new!) might be going on.  It’s why we do what we do. In hydrogeology, there remains much to explore, especially at the inter-disciplinary mixing zones around the edges of our specialty. And we’ll need new concepts, new methods, and new connections to move our understanding forward. Scientists from academia and government and industry and other groups can all contribute to this quest. For graduating PhDs, hopefully this leaves you with multiple career path options for joining in the fun.

a In Canada, besides Environment and Climate Change Canada there are also PhD-holders doing groundwater-related research in Natural Resources Canada, Agriculture and Agri-Food Canada, and the National Research Council. In the U.S., much great groundwater research is carried out by the U.S. Geological Survey, with research also carried out by other federal and state agencies. Many other countries have similar geological or environmental departments or agencies with PhDs doing some or much research.  You can look these up on the web, though often government scientist pages aren’t nearly as good as those for academia.

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Jim Roy is a Research Scientist at Environment and Climate Change Canada. His current research focuses on: groundwater contaminant impacts on surface waters and aquatic ecosystems, groundwater contributions of phosphorus to surface waters, potential leakage of Alberta oil sands tailings ponds to the Athabasca River, and groundwater and gas systems. Find out more about Jim by clicking on the links below.

Twitter Page | Research Profile

Hydraulic fracturing close to groundwater wells

Hydraulic fracturing close to groundwater wells

Post by Scott Jasechko, Assistant Professor of Water Resources with the Bren School of Environmental Science & Management, at the University of California, Santa Barbara, and by Debra Perrone, non-resident Fellow at Water in the West and an Assistant Professor, also at the University of California, Santa Barbara, in the United States.

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In December, 2016, the Environmental Protection Agency finalized a report [Ref. 1] on hydraulic fracturing and drinking water resources that, among other conclusions, states:

(a) Quote from [Ref. 1]: “scientific evidence that hydraulic fracturing activities can impact drinking water resources under some circumstances”

(b) Quote from [Ref. 1]: “When hydraulically fractured oil and gas production wells are located near or within drinking water resources, there is a greater potential for activities in the hydraulic fracturing water cycle to impact those resources.”

Tens-of-millions of Americans rely on groundwater stored in aquifers for drinking water. Because it is possible that hydraulic fracturing activities can impact water resources (i.e., quote (a) above), and because groundwaters located close to hydraulic fracturing activities are more likely to be impacted than those farther away should a contamination event occur (i.e., quote (b) above), it is important to assess how many domestic groundwater wells are located close to hydraulically fractured wells.

In a recent study [Ref. 2], we assessed how close domestic groundwater wells are to hydraulically fractured wells, and to oil and gas wells (some hydraulically fractured, some not). Due to consistencies limitations in both oil and gas and groundwater well datasets, we limited our analysis to groundwater wells constructed between 2000-2014, hydraulically fractured wells likely stimulated during the year 2014, and oil and gas wells producing in 2014.

Our study has two main findings.

First, we found that most (>50 %) recorded domestic groundwater wells constructed between 2000 and 2014 exist within 2 km of at least one hydraulically fractured well in 11 US counties (Fig. 1). Further, about half of all recorded hydraulically fractured wells that were stimulated during 2014 are located within 2-3 km of at least one domestic groundwater well. We suggest these regions where groundwater wells are frequently located near hydraulically fractured wells might be suitable areas to focus limited resources for further water quality monitoring.

Figure 1. The percentage of domestic groundwater wells that were constructed between 2000 and 2014 that have a recorded location that lies within a 2 km radius of the recorded location of at least one hydraulically fractured well that was stimulated during the year 2014.

Second, we assessed the proximity of oil and gas wells being produced in 2014 – some hydraulically fractured but others not – and groundwater wells. We found that many domestic groundwater wells are located nearby (<1-2 km) at least one oil and gas well, and, that actively-producing oil and gas wells are frequently located nearby at least one domestic groundwater well (Figure 2). Many of the potential contamination mechanisms associated with the construction, stimulation and use of hydraulically fractured wells are also associated with conventional oil and gas wells, including potential for spills on the land surface and well integrity failures [Ref. 3]. Therefore, assessing potential water quality impacts resulting from activities associated with oil and gas production derived from both hydraulically fractured wells and from conventional oil and gas wells is important.

Figure 2. The upper panel shows the distance between recorded oil and gas wells producing in 2014, and recorded domestic groundwater wells constructed between 2000 and 2014. The lower panel shows the distance between recorded domestic groundwater wells constructed between 2000 and 2014 and the nearest recorded oil and gas wells producing in 2014 (see Ref. [2] and references therein for data sources).

We conclude that (i) publicly-available groundwater well construction data are critical for managing groundwater resources and completing water quality risk assessments (see Ref. 4 for data quality information), and emphasize that not all states currently provide access to digitized groundwater well construction records (e.g., Figure 2), (ii) hotspots exist where activities related to oil and gas production occur nearby domestic groundwater wells, and these regions may be targeted for further groundwater quality monitoring, and (iii) assessing how frequently activities in the hydraulic fracturing water cycle impact groundwater quality may be vital to securing high quality water pumped from many domestic water wells where oil and gas production is common.

Figure 3. Hydraulically fractured well situated close to an irrigation system in California’s San Joaquin Valley.

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References:

[Ref. 1] U.S EPA. Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States (Final Report). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-16/236F, 2016. Accessed from https://www.epa.gov/hfstudy November 15, 2017.

[Ref. 2] Jasechko S., Perrone D. (2017). Hydraulic fracturing near domestic groundwater wells. Proceedings of the National Academy of Sciences.

[Ref. 3] Vengosh A., Jackson R. B., Warner N., Darrah T. H., Kondash A. (2014). A critical review of the risks to water resources from unconventional shale gas development and hydraulic fracturing in the United States. Environmental Science & Technology 48, 8334-8348.

[Ref. 4] Perrone D., Jasechko S. (2017). Dry groundwater wells in the western United States. Environmental Research Letters 12, 104002.

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Scott Jasechko’s research focuses on fresh water resources, and uses large datasets to understand how rain and snow transform into river water and groundwater resources.

Find out more about Scott’s research at : http://www.isohydro.ca.

 

 

 

Debra Perrone  is interested in the multifaceted interrelationship between water, energy, and food resources. Her research explores how the interactions among these resources affect decisions and tradeoffs involved in water resource management.

Find out more about Debra’s research at: http://debraperrone.weebly.com/.

How did our planet get its water?

How did our planet get its water?

Post by WaterUnderground contributors Elco Luijendijk and Stefan Peters from  the University of Göttingen, in Germany.

After my first ever scientific presentation, someone in the audience asked a question that caught me off guard: “Where does the groundwater come from?”.  “Ehm, from rainfall”, I answered. The answer seemed obvious at the time. However, we did not realize at the time that this is actually a profound question in hydrogeology, and one that is rarely addressed in hydrology textbooks and courses: “How did our planet get its water?”. To find out how far science has come to answering this question I (EL) joined up with a geochemist and meteorite expert (SP) to write this blog post.

We are lucky to live on a planet of which ~71% of the surface is covered with water, located mostly in rivers, lakes, glaciers and oceans at the surface and as groundwater in the shallow subsurface. Liquid water sustains life on our planet and seems to play a critical role in plate tectonics. And incidentally, it also to gives hydrogeologists something to study. Liquid water is so important in sustaining life, that the search for life on other planets in our solar system or beyond always focuses first on finding planets with liquid water.

Not only do we have abundant liquid water, we seem to have just the right amount. Compared to our direct planetary neighbors, Mars and Venus, we are extremely lucky. On the surface of Mars, at present, water mainly occurs as ice, whereas tiny amounts of water vapor are present in the Martian atmosphere. Venus also has minute amounts of water vapor in the atmosphere, but its blazingly hot surface is entirely devoid of water. In contrast to Mars and Venus, some objects in the solar system that are further away actually have too much water. Take for instance Enceladus, a moon of the planet Saturn, at which an icy crust overlies a 10 km deep water ocean. The amount of water on Enceladus is so large that it causes a wobble in the rotation of this moon, which is one of the reasons why this large volume of water was discovered in the first place. Clearly Enceladus is great for ice-skating, but probably not for sustaining land-based life similar to humans.

Figure 1: From left to right, Venus, Earth and Mars. Which one would you like to live on? Source: ESA (link) .

So how did we on Earth get so lucky?

It turns out that this depends on which scientist you ask. There are two theories:
Theory 1: The major building blocks of the Earth contained water from the start. This water then accumulated at the surface of our planet (by “degassing” from the mantle) and formed the oceans and the hydrosphere.
Theory 2: The major building blocks of the Earth were bone dry, and most of the water was delivered by comets and water-rich asteroids some time after most of our planet’s mass had formed by accretion.
So far, scientists do not have reasons to discard either of these theories, but there are two important arguments in favor of water being delivered after most of the planet had already formed:

Earth formed in a hot region of the solar system from which molecules with “low” condensation temperatures such as water had largely been removed before planetary accretion started (Albarède, 2009). Secondly, the ratio of heavy to light water in Earth’s oceans is similar to that of water in some comets and asteroids (Hartogh et al., 2011). Although you may not have noticed this when you last opened your water tap, a very small fraction (0.016 %) of the water on our planet is heavy, because it contains an extra neutron. The similarity in heavy water composition between asteroids and comets and Earth’s oceans does not prove that water on Earth was delivered by comets, but it certainly is consistent with this scenario. To make matters more complicated, however, the recent European space agency mission Rosetta to the water-rich comet 67P/Churyumov–Gerasimenko found that it has a very different ratio of heavy to light water than our oceans, which certainly complicates the debate.

Figure 2 Comet 67P/Churyumov-Gerasimenko losing water (and dust) as it gets closer to the sun. Source: ESA

Interestingly, neither theory can directly explain why our direct planetary neighbors, Mars and Venus, are so dry compared to Earth. So is it possible that these planets once were similar to Earth, and contained more water in their early days than that they do now?

Due to the high surface temperatures at Venus, any liquid water near the surface would immediately evaporate and diffuse into the atmosphere of the planet as a gas. We know that due to the lack of a protective magnetic field on Venus, solar winds continuously erode the atmosphere of the planet. If Venus had abundant water in the past, such erosion by solar winds would therefore have effectively stripped water from the planet’s atmosphere. Similar to Venus, Mars also does not have a protective magnetic field, but the temperatures and pressures at the Martian surface are significantly lower than at Venus’ surface, allowing water to be present at the surface as ice. In fact, Mars may have had a denser atmosphere in the past that allowed liquid water to be present at the surface. Nowadays, erosional features such as channels are the dry witnesses that water indeed once occurred as a liquid on the surface of the planet.

Figure 3. Dry channels (in inverted relief) in the Eberswalde delta on Mars as seen by NASA’s Mars Global Surveyor (link)

As a summary, we have an idea on why our planet was lucky enough to keep large amounts of water compared to Venus and Mars. However, do we know how our planet got its water in the first place? Unfortunately we are still not sure. There is hope though: we keep getting closer to the answer thanks to recent research on the composition of water on our planet and comets and asteroids in the solar system. So stay tuned, there’s a good chance that science will be able to answer this question in the coming years…

References
Hartogh, P. et al. (2011), Ocean-like water in the Jupiter-family comet 103P/Hartley 2, Nature, 478(7368), 218–220.
Albarède, F. (2009). Volatile accretion history of the terrestrial planets and dynamic implications. Nature, 461(7268), 1227-1233.

The great American groundwater road trip: Interstate 80 over the Ogallala Aquifer

The great American groundwater road trip: Interstate 80 over the Ogallala Aquifer

 


Authored by: Sam Zipper – Postdoctoral Researcher in the Department of Civil & Environmental Engineering at the University of Wisconsin-Madison


In late July, my wife and I loaded the dog into the car, cranked up the water-related tunes, and drove over a few million cubic meters of water. No, we haven’t traded in our sedan for an amphibious vehicle – rather, we were driving west, across Nebraska, on the Interstate 80 highway. While this may be a relatively boring road trip by conventional standards, it does provide an opportunity to drive across the famous Ogallala Aquifer, a part of the High Plains Aquifer system.

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The wide reaching Ogallala Aquifer 1. The red line shows Interstate 80’s route.

While the geological history of the Ogallala is described in more detail elsewhere; the short version is that sediment, eroded off the Rocky Mountains over many millions of years, filled in ancient river channels, eventually creating the flat plains that characterize much of Nebraska today. Despite the flat landscape, however, the sights you’ll see along I-80 exist in their present form almost entirely due to this vast underground supply of water.


Irrigation

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A center-pivot irrigation sprinkler. A common sight over the Ogallala 2.

It’s estimated that upwards of 90% of the water withdrawn from the Ogallala is used for agricultural irrigation. Driving through western Nebraska, 90% seems like an underestimate. Center-pivot systems stretch away from the interstate as far as the eye can see, and it’s hard to imagine what this landscape would look like without the water from the Ogallala. While groundwater levels have declined in the most heavily irrigated parts of Nebraska compared to predevelopment conditions, they’ve fortunately stabilized over the past ~30 years; the most serious drawdowns are occurring further south, in Western Kansas, Oklahoma, and the Texas Panhandle.


The Mighty Platte

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The mighty Platte River. Photo by Sam Zipper.

The Platte River stretches from the Rockies to its confluence with the Missouri River in eastern Nebraska, and I-80 follows the Platte through most of Nebraska. Along the way, the Platte is receiving water from surrounding groundwater systems.  This process of groundwater discharge to streams (often called baseflow), is particularly important for sustaining flow in the river during dry periods, along with the ecosystems, agriculture, and municipalities that depend on this water supply. For a more beautiful look at the Platte than my cell phone camera offers, check out the Platte Basin Timelapse project, which uses photography to explore the movement of water through the basin.


The Namesake

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Ogallala Nature Park welcome sign. Photo by Sam Zipper.

The Ogallala is named after Ogallala, NE, a tiny town about a half hour’s drive from the Colorado border. The aquifer is named after Ogallala because that’s where the geologic “type locality” is – a fancy way of saying, they found the Ogallala formation here first. While we didn’t venture into the town of Ogallala itself, we did stop at the lovely Ogallala Nature Park just off the interstate for a stroll among the phreatophytic vegetation lining the banks of the Platte. Phreatophytes, such as the cottonwoods common to Nebraska, have evolved to have special roots which can extract water directly from groundwater when soil moisture supplies are low, thus allowing them to survive in the sandy, well-drained banks of the Platte.

Do you have any hydrogeologic highlights we should investigate on our drive back to Madison? Let me know via the comments below!


Picture Sources

https://upload.wikimedia.org/wikipedia/commons/thumb/4/44/Ogallala_saturated_thickness_1997-sattk97-v2.svg/2000px-Ogallala_saturated_thickness_1997-sattk97-v2.svg.png

http://water.usgs.gov/edu/pictures/full-size/irrigation-sprinkler-large.jpg


About the author:

Sam Zipper‘s research interests lie broadly at the intersection of humans and the environment, focusing on feedbacks between subsurface hydrology, vegetation dynamics, soil water retention characteristics, and climate & land use change that cut across the disciplines of hydrology and hydrogeology, soil science, agronomy, and ecology.  He is an ecohydrologist at the University of Wisconsin-Madison.

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FloPy: A Python interface for MODFLOW that kicks tail!

FloPy: A Python interface for MODFLOW that kicks tail!

Authored by: Kevin Befus – Assistant professor, Department of Civil and Architectural Engineering at the University of Wyoming


Groundwater modeling is getting better. Models are becoming more sophisticated with simpler interfaces to add, extract, and process the data. So, at first appearances, the U.S. Geological Survey’s (USGS) recent release of a Python module named FloPy for preparing, running, and managing MODFLOW groundwater models seems to be a step backwards.

Oh, but it isn’t.

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First, a couple disclaimers. Yes, at the time of writing this I work for the USGS and use this new Python module for my research. Did I have to use FloPy? No. Am I glad I did? YES! Before using FloPy, I dabbled in the various non-commercial MODFLOW interfaces but got bogged down on how many drop down menus, pop-up menus, wizards, and separate plotting programs with their own menus were needed to make a meaningful groundwater model on top of a new lexicon of variable names (IUPWCB must mean “internally unknown parameter with concentrated bacon”, right?).

FloPy made its official debut in February 2016 with a Groundwater methods report 1. Bakker et al. do an excellent job telling us why we should use FloPy. I’ll leave that to you and tell you what I think.

Here’s what is great about FloPy:

  1. FloPy is 100% MODFLOW. No tweaks to anything. You choose the executable file you want it to use or compile it yourself, and you’re off!
  2. You have the near-infinite data management, manipulation, and plotting capabilities of Python at your fingertips. Python has a lot of packages. It can be overwhelming. You can rely commercial packages like ESRI’s arcpy if you want, but there’s a list of free libraries that give you even more freedom to get the input data just right. Since I mentioned freedom, here’s the list of free libraries I find useful but it is in no way an endorsement nor exhaustive: scipy, numpy, gdal, osgeo, fiona, shapely, cartopy, pyshp, pandas, matplotlib, and let’s not forget…flopy!
  3. It’s easy to duplicate and alter an existing model. Once you have your script perfect for running a particular groundwater model, you can take pieces of it to make a slightly altered version, or you can pop it in a loop that runs through your uncertain inputs for sensitivity testing. Change your grid with the flip of a variable, and make sure that mesh converges!
  4. Loading other MODFLOW models works great. Say you want to run someone else’s model with slightly different recharge, but their recharge is variable in space. Since FloPy incorporates numpy’s grid/matrix handling capabilities, you can change individual entries with row-column selections or change the whole recharge grid by multiplying it by either a single number or say a random matrix with a normal distribution and some added noise. If you just want to use their recharge data to run your own model, you can save the position coordinates (they have hopefully provided you with their coordinate system and model transformations) and recharge arrays to your very favorite format (csv, nc, mat, tif) and load it later as a matrix to add to your model, all in a single Python script.
  5. Building off of the ability to load or create MODFLOW models, FloPy has functions for plotting 2D map or cross-section views of the model discretization, boundary conditions, and results. Shapefiles can be included in these plots if they are in the same coordinate system as the model or extracted from the model (ever want a polygon feature of every model cell with attributes for every property of that cell?). I do my own shapefile manipulations in Python, but FloPy has some great plotting tools built in.
  6. You already have the data in Python. See what adding a low permeability layer does to spring discharge. Then, with the model made, you have to make sense of it. Maybe develop some interesting spatial or time series analyses. Enter Python. Plotting with matplotlib also makes beautiful, journal article-worthy figures…with enough sweat and tears from your end (not as many as you may think). Yes, this is a repeat of 2), but, seriously, it’s in PYTHON!
  7. FloPy is totally free. Python is free. Tons of science-oriented libraries in Python are free.

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Here’s a flashy example.  It is straightforward and only takes one script to create a SEAWAT model from scratch and plot the 2D steady state salinity distribution and flow vectors for a simple Henry 2 problem based on a slightly edited FloPy example script.  There are more than a dozen example scripts available on the FloPy site as well as a very cool capture ratio script provided in the methods report 1.

For the groundwater educators out there, a FloPy groundwater model script can be paired with homework questions that get students testing how changing hydraulic conductivity in certain parts of the model changes the water table configuration. Or maybe a new well needs to be drilled on a plot of land near a spring… The scenarios are endless. Students can develop a fundamental understanding of groundwater flow while getting experience with both groundwater modeling and computer programming. Win, win, and win.

Essentially all of the standard MODFLOW packages are operational in FloPy, and there are varying levels of support for some of the specialized MODFLOW compilations and processing tools (e.g., MODFLOW-USG, MODFLOW-NWT, MT3DMS, SEAWAT, PEST, and MODPATH). PEST and MODPATH are currently not executable with FloPy, but these features will probably be added in a future release (I have made my own klugy modules for running ZoneBudget and MODPATH that interface reasonably well with the rest of FloPy).

Get on your way and give FloPy a try today!


Links

The Python package is available online at https://github.com/modflowpy/flopy.

The documentation is available online at http://modflowpy.github.io/flopydoc/index.html.

The USGS FloPy page is http://water.usgs.gov/ogw/flopy/.


References

Bakker, M., V. Post, C. D. Langevin, J. D. Hughes, J. T. White, J. J. Starn, and M. N. Fienen (2016), Scripting MODFLOW Model Development Using Python and FloPy, Groundwater, doi:10.1111/gwat.12413.

Henry, H.R., 1964. Effects of dispersion on salt encroachment in coastal aquifers. In: Cooper, H.H. (Ed.), Sea Water in Coastal Aquifers: U.S. Geological Survey Water- Supply Paper 1613-C p. C71–C84.


About the author:

Kevin Befus is a groundwater hydrologist with geology and geophysics experience — examining geological, biological, and chemical processes, especially considering their connections to water across scales.

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