7 million. That’s roughly how many people are added to our planet's population each month. Such a staggering growth rate shines a bright light on resources like food, water, and energy. Will there be enough to go around? Our weekly series, The Sustainables, profiles the folks doing their part to ensure that there is.
Last month, a U.S. Department of the Interior report re-confirmed what climatologists and hydrologists have known for years: The water supply of the American West, already threatened by over-consumption and overpopulation, will diminish significantly by mid-century once climate change hits its full stride.
The yearly flows from three lynchpin river basins—the Colorado, Rio Grande, and San Joaquin—could drop by up to 14 percent by 2050. These three rivers provide water to eight states, including California.
To better understand the West’s looming drought—and the myriad ways it might be prevented—TakePart spoke at length with Peter and Hadley Arnold of the Arid Lands Institute (ALI) at Woodbury University in Burbank, California.
Architects by trade, the husband and wife team co-founded ALI in 2008 as a water infrastructure think tank to cultivate students who are dedicated to designing solutions in the face of water scarcity and climate change.
The State of Water in the American West
TakePart: The same amount of water that existed billions of years ago exists today, so why then is the world, specifically the American West, staring at a water shortage crisis?
Hadley Arnold: The projected impacts on the U.S. West are not necessarily that there will be less water, but that the hydrologic cycle will be re-allocated in ways they we’re not designed to handle well and efficiently.
So, if you add that into an equation that also shows a growing population and an already over-taxed water supply…every drop of water in the Colorado and the Sierras is not only allocated, it is over allocated.
If that changes to less snowmelt and more rainwater, it becomes a design question because right now the west rids itself of rainwater and depends entirely on snowmelt. That shift in hydrologic cycle is what ALI is designed to address.
Peter Arnold: I would also say that part of the crisis is about the amount of the water that we are using. A significant portion of our water resources are brought in from very large distances and the importation of that water requires an enormous amount of energy.
Presently, those energy sources are primarily thermo-electric in nature—meaning that they require fossil fuels to generate electricity. That’s part of this kind of gerbil wheel effect: that the more thermo-electric supplies that you use to generate electricity, the bigger the climate change impacts, the more population increases, the more you use water in scare areas, the more we need to import water.
Like Politics, All Water is Local
TakePart: How important is the ability to capture rain and flood water to the future of water in the American West?
Peter Arnold: In order to decrease at a significant level the amount of water that we’re bringing in from these imported sources, and hence the energy that’s required for those sources, we really need to take advantage of more localized water resources. This comes in two forms: one is rainwater, stuff that precipitates out of the sky; the second are any flood events that generate storm water run-off. Storm water run-off, currently, is treated as a nuisance. Storm channels and the L.A. River are all designed to carry away fast and as efficiently as possible. This is an area that we need to completely change consciousness on. And need to identify ways of capturing that run-off, ponding it, and re-using it.
TakePart: Is there a cheap way to capture it? In theory, your solution is great, but I would guess it is expensive to implement, right?
Hadley Arnold: One of the things that we’re trying to look at in this specific case study is Burbank as a medium size city, as kind of a model or demonstration project. How do you identify where the highest yield, lowest cost opportunities are for harvesting water? It turns out there are sort of a range of scales that are available to us, and depending on a communities needs, budget, time frame, can be employed.
For example, in Burbank, when they’re looking at the upgrade of public spaces in public parks and a certain amount of money has been allocated for a surficial retrofit of a public surface, is it more cost effective to budget now for an additional performance layer from that park? To have it be an on-site wastewater treatment or local storm water runoff percolation basin—how do you start to incorporate infrastructure performance into existing spaces?
You certainly can’t wave a magic wand, at least not inexpensively, and get every surface or every building type hydrologically functional. But, you can look strategically at where your best opportunities are.
TakePart: So when ALI formulates these re-designs, you have economics on the brain, right?
Peter Arnold: Absolutely. That’s an important aspect. If you were to take a time slice of what exits now, you might hear that it is actually more expensive to capture this rainwater, but if you start to account for the amount of energy that this rainwater or storm water would require if it were imported, it becomes very economically viable.
The Water-Energy Nexus
TakePart: What’s the water-energy nexus and why does it need to be untied?
Hadley Arnold: Our cities don’t exist where water exists, so we made a half a continent investment in using energy to extract, pump, distribute and treat remote water sources and bring them to western cities. So, it (the water-energy nexus) simply means a high embodiment of energy in every drop of water that we drink or wash our cars with or use to water our lawns. Our goal is not to supply more water to the West, it is to supply less energy intensive water to the West, which really requires localized, and, wherever possible, gravity path, soft path, low tech, localized infrastructure solutions as opposed to large scale engineering solutions.
Help from Ancient Rome?
TakePart: In the Bible. Ecclesiastes. “That which has been is what will be, that which is done is what will be done, and there is nothing new under the sun.” How can studying Roman aqueducts help you fix the problem?
Hadley Arnold: What’s common with a lot of (the water infrastructure used throughout history) is that they are low in intensive energy, principally gravity fed, and designed, managed, implemented, and governed by their users. And that’s a model for infrastructure that we are interested in—the idea that indigenous infrastructure might re-teach us how to be participatory citizens in resource management is very interesting to ALI.
Peter Arnold: Another way to say that is another model for future water infrastructure should not only be less carbon intensive and more intelligently designed, but they also need to be highly participatory—meaning that they have to be sited.
TakePart: What does that mean?
Peter Arnold: They can’t be buried, you have to understand them and…
TakePart: ...are you saying that, for example, because our sewers are underground, it’s kind of an out-of-sight, out-of-mind kind of thing? If they were above ground the public would care more, perhaps?
Hadley Arnold: To a certain extent, yes. Design can actually give users useful information for calibrating their own volume, rate or quality of a resource they’re using. We’re not the first to pose that revealing something promotes a form of mindful use that we would advocate. What we’re trying to say, not unlike Ecclesiastes, is that water is a primary shaper of human behavior and urban form, as opposed to just a technological driver of growing economies.
TakePart: Can you think of something that a person can do in five minutes or for under $5 to help save water?
Hadley Arnold: Drink your tap water would have to be my quick and easy answer.
TakePart: Where is ALI in five years?
Hadley Arnold: Great question. I would like to say that we are offering design planning and design services to cities and communities across the west and that we’re serving students from across the west.
TakePart: Los Angeles County. May 2061. What’s the water situation like?
Peter Arnold: Groundwater tables have come up between 20 and 50%. We have managed to cut imported supplies (of water) by 25 to 30%. We have managed to look at localized storm water capture by offsetting about 25% of those imported supplies at a minimum.
Hadley Arnold: We’ve got four grades of water at home. The water that we drink. The water we’ve just used. The water that’s used for flushing waste. And what is sunk into the aquifer. We’re working on a multi-tiered water system. Building codes have been rewritten so that the design of roofs, water storage systems, and how it is that we grade out sites are all aligned toward a maximum retention of water as opposed to what they are now which is the maximum shedding of water.