Lake Powell is the country’s second-largest reservoir. Dropping water levels leave bath tub ring on surrounding rock face, exposing rock that had been covered for years.

Lake Powell is the country’s second-largest reservoir. Dropping water levels leave “bath tub ring” on surrounding rock face, exposing rock that had been covered for years.

Water and Energy Introduction


Look to this screen,

whether your computer or phone. Look to your house lamp, ceiling fixture or streetlight hanging over the pavement. Think of your clothes thrown in the wash, the last shower you were able to take, or the last meal you were able to prepare without traveling to hunt the ingredients yourself. Try to think of any regular activity in your daily life that water and energy aren’t at least partially responsible for. The ongoings in large part are behind the scenes, but this “Water-Energy-Food Nexus” is crutial to the type of lives we’ve grown accustom to living in modern day.

The Greeks, at their intellectual peak, are credited to be the first civilization to harness piped water supply distribution systems1. Rome also dealt with supply in a similar way, but ramped up technological innovation every time the capital became too large for the infrastructure2. Later metropolises, for example Paris and London, also continually dealt with the strains of water supply, food supply, and waste treatment for their ever growing populations. Stories of societal adaption to resource management challenges span the history of human kind, but something about today seems - different.

Never before have 7.3 billion Homo sapiens roamed the Earth at the same time3. Barring absolute scientific catastrophe, it is certain this climate has never seen an atmospheric carbon input rate at the level experienced in the years since the industrial revolution. At no point in the cosmic narritive have resources in this planet been manipulated and exploited in the same ways that are now second nature to us and our economies. Times like these are unprecedented, to say the least, and repercussions of the increased climate variablility are already being felt: increase in number and intensity of hurricanes, stronger heat waves, increase in number and intensity of droughts, likely increase in crop failures, increase in number and intensity of floods, extinctions, disappearing shorelines, increasing average wind speeds, increasing average ocean wave heights, groundwater contamination, the Jonas Brothers just got back together…

So, where do we go from here?



This is an extraordinarily complex question, but this article dips its toes in. Here, we discuss possible sources of water stress by investigating 2015 water consumption data in the United States. The United States Geological Survey (USGS) releases a comprehensive report on national water quality and consumption habits every 5 years, so the values and trends discussed are as recent as is available. Central to water scarcity is amount of withdrawal in an area, and whether this value is a major contributor to the problem. Withdrawal can involve either fresh or saline water, and either be from surface or underground areas. What the water is withdrawn for, however, is really what will become important if (or when) some areas start to seriously face issues with supply. The data is recorded by county and organized into climate regions for analyzation sake.

Withdrawal vs. Public Supply

Figure A and Figure B reflect total withdrawals and total population supplied, respectively. This is the most immediate relationship that came to mind when speculating about what would have significant influnence on water use.


On the other hand, these graphs clearly show that areas of highest water use do not strongly correlate with level of distribution. The South proves to be largest comsumer of water in the nine regions while the Northeast serves the most people. In order to take this even further, it is often helpful to break down data per capita. Though Figures A and B tell of aggregate withdrawal and supply seperately, per captia supply consumption could possibly give insight to how efficiently water in the area is used.


This is good and interesting. Per capita use of public supply exibits same major trends as Figure A, but does not follow it exactly. There must be other factors at play affecting total withdrawals across the regions.

Other Water Consumption Factors


To get a better understanding of public supply and total withdrawal correlation, we are now going to harness the power of scatter plots and linear regression.



Interestingly enough we find that data presented in this fashion conflicts the conclusions we reached using bar plots. Population supplied and total withdrawal seem correlated here, but there could be many reasons for this. Lets see if states induvidually express this trend as well.

States


This collection of plots may seems overwhelming at first, but take a little time to skim through them and the main idea is evident. There is a huge amount of variability! When induvidualized by state, this positive relationship between population supplied and total withdrawal largely breaks down. For times sake, the states in focus moving forward are only located in regions where the correlation appears the weakest. This implies some other factor exercises large influence over the consumption habits of the citizens.

Irrigation and Energy in the South Region


One of the most collectively uncorrelated regions is expressed in Figure K: the South. Arkansas, Louisiana, Kansas, Missouri and Oklahoma all present data that seems strongly skewed by an outside force. Here it is again as a refresher.

Given what is known about this area of the country, agriculture seems a likely culprit for the disparity in water consumption. Then again, thermoelectric power generation is still utilized all over the country, and this too needs large amounts of water to produce. Lets see if either consumption factor shows up in the plots.


Our hypothesis proved correct! Figure N demonstrates that overall, irrigation causes counties of similar population size to vary widely from each other in amount of water consumption. It also shows that out of the six, Arkasas experiences incredible amounts of consumption in counties of relatively average size. While irrigation shows to tie up loose ends in Arkansas and Oklahoma, states like Texas and Louisiana still dont show outstanding signs of agricultural impact. When compared against energy use, however, both Texas and Louisiana show their extremely strong relience on thermoelectric production. This isnt to say the other states aren’t effected, but it’s most prevelent in those two areas. It is incredibly interesting to study these two plots and gather that provinces in such proximity spend their water on such different processes. In terms of long term drying climate mitigation, Texas and Louisiana might find it in their best interests to migrate away from traditional energy sources towards more renewable ones that use less water. Arkansas and Oklahoma, on the other hand, could see huge negative impacts to their agricultural economies with decreases in available water. Things would be much easier if there was a one size fits all approach to solving water stress, but clearly even places only tens of miles from each other can seek differing solutions.

Energy and Irrigaiton Overall


Further investigating the extremely water intensive practice that is thermoelectric production, Figure P compares saline and freshwater consumption with power generated. It’s seen that most U.S. counties have input combinations that use some mixture of the two. Three notable communities, however, stand apart from the rest. The pink point depicts Maricopa County, Arizona that is home the largest power plant in the United States by 2015 net generation4. Normally, this would be a cause for concern in a drying place like the Southwest. In contrast, this plant actually uses wastewater overdraft from a nearby Arizona wastewater facility to meet its immense cooling needs. Unlike many other thermal plants in the area, this giant has found a way to avoid relying on the Colorado River for freshwater support. This is likely why its position on the plot couples peak energy production with relatively low level of fresh and saline water consumption. The other two points represent Salem County, NJ (orange) and Fulton County, IL (red). The functionality of the plants represented prove to greatly depend on their locations. Salem County, for example, sits on the shore of Delaware Bay and consumes mainly saline infused water from the Delaware River as source of cooling. Though the plant continues to draw from the water body, their permit for uptake ran out in 2006, and backlash from citizens is evident. Because the ocean takes part in feeding the Delaware Bay, concerns in this area center around negative effects on the animal life and increased river temperatures rather than drying climate mitigation5. Further information is needed to explore why the data for Fulton County expresses such high freshwater consumption for thermoelectric production. According to the research of this article, there seems to be no power genreating plants of any kind residing in this county.6 If you, as the responsible scientific reader you are, live in this place or find an answer to this question, please reach out and make your results known.

Closing

As mentioned before, solutions to a changing climate are not one size fits all. Energy, water, and food play enormus roles in propelling us forward everyday. We live the lives we enjoy because of the amazing ways humans have figured out how to utilize and distribute the resources around the planet. Keep in mind, analyzation in this article was only a dip into the vast resovior of data available to us about the nexus. Real threat exists to normalcy of the modern world, but we’ve always found ways to innovate ahead.

References

1“The History of Plumbing - CRETE”. theplumber.com. theplumber.com. Retrieved 26 March 2014.
2Sedlak, David. Water 4.0: The Past, Present, and Future of the World’s Most Vital Resource. Yale University Press, 2014. JSTOR, www.jstor.org/stable/j.ctt5vksm5.
3Cumming, Vivien. “Earth - How Many People Can Our Planet Really Support?” BBC, BBC, 14 Mar. 2016, www.bbc.com/earth/story/20160311-how-many-people-can-our-planet-really-support.
4Conca, James. “The Ten Biggest Power Plants In America – Not What You Think”. Forbes.com. Retrieved 2017-02-24. 5Montgomery, Jeff. “Nuclear Plant Cooling-Water Intake Debate Heating Up.” Delawareonline, 19 Sept. 2015, www.delawareonline.com/story/news/local/2015/09/18/salem-cooling-permit/72420528/.
6“List of Power Stations in Illinois.” List of Power Stations in Illinois, 2017, ipfs.io/ipfs/QmXoypizjW3WknFiJnKLwHCnL72vedxjQkDDP1mXWo6uco/wiki/List_of_power_stations_in_Illinois.html.