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Does Fracking Mess Up Our Water Supply?

by gregladen on March 14, 2013 · 3 comments

Tap water lights on fireFracking, or Hydraulic Fracturing, is a method of extracting hard-to-get oil and gas from shale. For the most part, fossil fuels originally formed in shale, which was in turn laid down by near surface life in anoxic seas. Sunlight powered a high turnover of near surface plankton, algae, and bacteria, but oxygen-poor conditions just a little deeper in the sea made it unlikely for much of that life to be recycled through other life forms. So, during periods of anoxic seas, which lasted for millions of years now and then in earth history, much of that organic material from near the surface of the ocean settled into the sea floor mud where it became buried and incorporated into the growing layers of sediment. This was eventually transformed into oil and gas rich shale. (For a detailed overview of that aspect of earth history, see this fascinating book.) Eventually, some of that oil and gas collected in deposits that could be easily removed through drilling. Once this oil and gas is removed, however, the remaining hydrocarbon fuels are much more thinly distributed in the shale. In order to access this fuel, modern day miners pump water mixed with sand and chemicals at high pressure into the shale, which causes it to fracture, allowing the gas and oil to accumulate and become more easily removed. It is a little like squeezing a few drops of the water out of a mostly dry sponge.


So, we have an important question to address: How much water is used in fracking, and does fracking pose a threat to the availability of clean and accessible water?


There is an awful lot of water on the Earth. But everyone knows from their earth or environmental science class in high school that what matters is not the total amount of water, but the water’s distribution. Most of the liquid water (not in glaciers, air-born vapor, or incorporated with other molecules in rock or living things) is sea water, which is both too salty to use for most purposes and inconveniently located far from points inland, being in the sea and all. Free flowing fresh water … rain, lakes, rivers, streams, and groundwater … makes up only a small part of the total water budget for the planet, and this free flowing water is very unevenly distributed. And, some of that is not so fresh. For example, in the Permian Basin in Texas, the site of the Black Gold Rush of bygone days, the groundwater is often brackish (meaning somewhat salty). I do not know this for a fact, but I suspect that this brackishness is the result, at least in part, of early oil drilling activities. (If you know, tell us in the comments!)


Fracking uses very little water, when you look at the overall budget of water. The use of water in fracking has been best studied in Texas and to some extent in Pennsylvania. Fracking in these two states is relatively high in water use per well. In Texas, fracking for oil and gas uses less than one percent of the state’s total water supply. It is important to note, however, that water is used in other mining activities as well, including coal extraction, so the total amount of water used in mineral extraction, including oil, gas, and coal, is closer to 2%. That does not sound like a lot.


However, as noted, fresh, usable, free flowing, accessible water (including lakes, streams, rivers, and groundwater that is not too deep) is very unevenly distributed. In some counties in Texas, where the Eagle Ford Shale is being exploited, the total amount of water used locally approaches or even exceeds 50%. Suddenly, that is a lot of water. In some cases, the draw-off of water for fracking has caused water in wells used for other purposes to drop significantly. In one study in a five county area in Texas carried out by the Wintergarden Groundwater Conservation District, fracking was shown to reduce the available water in the aquifer by one third. This problem has pitted Texas Cattlemen against Texas Oilmen. Interesting.


Also, once the water is used, you still have this water on hand, but it has been contaminated. Or, if you used brackish water to begin with, you still have brackish water but it is no longer where it originally was siting and minding its own business. It is now in a truck, or really, a whole bunch of trucks, in which it is driven to a "disposal well.” Disposal wells are deep wells into which the messed up fracking fluid is put, where it hopefully will not get into the fresh water supply for nearby communities. Except that it does, apparently, contaminate fresh water supplies at least some times. In addition, deep wells for fracking fluid disposal tend to follow fault lines, and the fracking fluid injected into them cause earthquakes. Though whether this is true has been controversial, it no longer seems to be. Fracking causes earthquakes.


A recent study in Pennsylvania showed where the water used for fracking comes from. In that case, about 4.4 million gallons was used over a period of less than a week to frack the average well. About 63% of that water came from nearby rivers and streams, 20% from public water supplies, 15% recycled from previously fracked wells in the area. About 2% of the total fracking fluid consisted of sand and chemicals used to make the water more effective and for other purposes. How much water is that? About 11,000 average American families use up 4.4 million gallons of water a day, which if you put it all in one place would fill six Olympic size swimming pools.


A report by EcoWatch looked at fracking across 26,339 fracking instances across 12 states. The reported water usage showed a great deal of variation by state in average water use per well, ranging from high numbers in Pennsylvania, Louisiana and Virginia (between 4.4 and 5.3 million gallons per fracking event) down to much lower numbers in California (168,000 gallons per fracking). The differences across regions could be attributed to a number of factors, but is probably mainly related to the nature of the rock being fracked. The total amount of water used in these 26,339 events was just shy of 66 billion gallons of water. That is roughly equivalent to a full day (24 hours) of flow over Niagara Falls. One single day of one major waterfall seems like both a lot and not so much depending on one’s perspective, but again, Niagra Falls is an unusual and spectacular concentration of water, and fracking is often done in places where there is much less available water.


Here’s the thing with fracking: We are not going to be fracking forever. It is a last ditch effort to extract hydrocarbon fuels from areas that were either depleted using traditional techniques or never exploited because the deposits were low quality. Also, the fracking itself is generally done in the early stages of exploitation in a given area. Once you’ve fracked, you put in wells and extract the oil or gas and are unlikely to frack again. In addition, the petrolatum industry dishonestly claims that fracking is not part of extraction, but rather, part of “exploration.” This is important because if one accepts this spurious argument, fracking falls under less strident rules regarding environmental effects and other regulations. This is how fracking can run under the regulatory radar. First, it may be less regulated if it is considered exploration, then the special considerations regarding fracking’s effects are addressed by a ponderous slow moving legal and regulatory process, so by the time we get our environmental protection ducks in a row, a lot of the fracking is done with. This means that across the possible range of effects fracking can have on a local aquifer and ecosystem, we can expect the worse or nearly so.


Back to water. In particular, let’s talk about water in Minnesota. Historians of yore identified a line that ran roughly north to south in the US, east of which traditional agriculture could be practiced without significant irrigation, and west of which one would need to irrigate to grow key crops like corn. This line ran through Minnesota. It was an oversimplification but a useful guide to understanding 19th century settlement pattern. The point is, if you want to farm in Minnesota, especially in the western and southern parts of the state (the prairies), you really have to irrigate. Irrigation stresses groundwater supplies. We have fairly uneven amounts of rainfall from year to year and over the months of a given year. Anyone who pays attention to the news in our state will know that every year farmers seem to have one problem or another having to do with water, but the problem varies between too much and too little, and often relates to when during the year the rain falls. Too little water in the Spring makes it hard for crops to take hold, too much makes it impossible to work many of the fields.


This problem affects other aspects of life as well, from municipal water supplies to fishing and other water activities to the levels of the Upper Mississippi required to use the nations greatest waterway to transport goods. Over the last 10 years or so, climate change has made this worse. Meteorologist Paul Douglas recently noted in a piece in Weather Nation that climate change is likely to move snowfall and other precipitation away from the middle part of winter towards the beginning and end. In and of itself a given seasonal distribution of snow may not be a big deal, but if water supply and irrigation systems are built to assume a certain pattern and that pattern changes, then costly adaptation may be required.


Generally speaking, climate change has warmed the atmosphere which means that the air holds more water on average than it did, say, 30 years go. But the increased energy of the atmosphere has also caused a qualitative change in the distribution of water. In a sense, one could say that the atmosphere has become better organized with respect to air currents that block the movement of air in some directions, and at the same time, certain air currents can now hold much more water than others. In short, the water vapor in our atmosphere is bunched up in both space and time. This means fewer mild rains and more heavy rains, often in the form of severe storms. Since the exact location of storm systems varies a great deal, this means that some areas that formerly received a certain average annual precipitation will a) have more precipitation overall; and b) a much greater variation in precipitation, leading to frequent periods of very little rain. This is how we can simultaneously have more really big and wet storms (and we do) and drought. The current national drought we are experiencing is part of a global drought being experienced in temperate zones in both the Northern and Southern hemispheres. Minnesota has experienced this drought to a lesser degree than states just to our south, but it has not been insignificant.


So here’s the thing. We are facing a future with a new climate reality that will involve, for Minnesota, long stretches of dry conditions (especially in the southern and western parts of the state) punctuated by flood-causing storms now and then. And now, fracking comes along and potentially adds a locally significant demand on a water supply that has been transformed from tenuous but manageable to stressed, possibly severely stressed. On top of this, fracking does not use water like irrigation does. Irrigation removes water from the local water supply and turns it into vapor and corn (or, in the unlikely event that you are growing something other than corn, whatever that may be). This is problematic in some ways, but it is not as polluting as fracking. Fracking takes water out of the water supply, messes it up with contaminants from the fracking process, and then puts it back into the water supply often in a less convenient location that can sometimes cause small earthquakes. In this way, a couple of percent demand on the water supply can translate into a much larger impact because contaminated water tends to mingle with uncontaminated water and the result is more contaminated water.


I wanted to talk about fracking and water, but while we are on fracking I’d like to make one other quick point: Fracking is stupid, just like building the Keystone Pipeline is stupid. We truly are approaching, and in fact are already experiencing, a climate crisis caused by the release of fossil carbon into the atmosphere. We have to stop doing that. The use of fracking to squeeze the nearly dry sponge is not what we should be doing right now.

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