Permaculture and the Looming Water Crisis

In our ongoing efforts to bring Permaculture to a mass audience, we often find ourselves framing Permaculture in terms of local food production or, even more misleading, gardening strategies. While these are certainly legitimate areas addressed by Permaculture, it is possible that we overlook what should be a major focus of our outreach activities: water management.

A fresh water crisis looms on the horizon, a crisis that is intimately linked with our other main ecological and energy concerns (climate change and Peak Oil immediately come to mind). The facts are startling: 97.5% of water on our planet is salt water, which is unfit for drinking or for agricultural use. Of the fresh water supply, over two thirds is frozen in glaciers and polar ice caps, and most of the rest is stored as ground water or in deep aquifers, which leaves only 0.9% available for human use. That’s 0.9% of the world’s total water supply that can be used for agriculture, industry and domestic uses.

And here are some more sobering figures:

Right now, 69% of fresh water is used for irrigation, with somewhere between 15-35% of irrigation withdrawals coming from underground aquifers. Such water use is clearly unsustainable.

15% of fresh water use is industrial. This may not seem like much, but bear in mind that the “spent” industrial water is generally polluted, often lethally toxic. Major industrial water hogs include power plants, which use water for cooling (a nuclear plant can use more than a billion gallons per day, and fossil fuel plants several million gallons of potable water daily) or as a power source (i.e., hydroelectric plants); ore and oil refineries, which use water in chemical processes (the worst case possibly being the aluminum processing industry); and manufacturing plants, which use water as a solvent.

Unsustainable water usage is causing irreparable damage to rivers and streams. Indeed, many major rivers are experiencing severe ecological stress (the Yellow River in China, the Chao Phraya River in Thailand), and many rivers are so overused that they dry up before reaching the ocean (most famously, the Colorado River and the Ganges).

In addition to all of these issues, there is also the growing threat from climate change. With the increase in the Earth’s average temperatures, the ice caps are melting, which is altering the ocean currents. As a result, a greater amount of precipitation is now falling world wide. While increased rainfall might sound like something positive, the actual results of this are troubling:

First, the increase in precipitation is not uniform. Many areas that were formerly “wet” are now experiencing prolonged periods of drought, including parts of sub-Saharan Africa, much of northern China, virtually all of Australia, Central and Southern California, and the Southeastern United States. Many of these afflicted areas are established agricultural regions, and the shortfalls in precipitation are usually made up by using unsustainable sources of water (e.g., aquifers).

Second, much of the increase in rainfall comes in the form of violent storm bursts, dropping enormous quantities of water in short time periods, with the bulk of the water running immediately off the land (and often carrying away valuable topsoil and toxic agricultural inputs in the process).

Third, the year-to-year fluctuations in precipitation for a given area are increasing in intensity, meaning that it is becoming less and less possible to make reasonable assumptions about the availability of rain water. I could easily continue with an entire article on the effects of climate change on the water supply, and it would merely scratch the surface of the issue (some excellent sources of information: Tim Flannery’s “The Weather Makers” and Fred Pearce’s “When the Rivers Run Dry: Water--The Defining Crisis of the Twenty-first Century”).

Water conservation and management will certainly become a major issue in the coming decade. In fact, many metropolitan areas are already experiencing fresh water shortfalls (see Perth, Australia, for an extreme example, as well as Atlanta, Georgia), and the number of afflicted areas will certainly grow. And while the numbers cited above would suggest the necessity for agricultural and industrial conservation measures, the reality is that it is the household users who find their water supply rationed. It doesn’t really matter where you live, either: there is simply no guarantee that any area on the Earth will remain “wet” in the coming years. Thus, we need as many strategies for water conservation and storage as we can uncover. Enter Permaculture.

Water strategies are at the heart of Bill Mollison’s theories of Permaculture. No matter whether the target is urban, suburban, agricultural or even large-scale industrial, Permaculture provides strategies that can help mitigate, if not solve, our looming water problems. Granted, the world would be a much better place if our current mono-cropped agricultural system was replaced by a sustainable and bio-intensive model, and there is no doubt that most industries could easily adopt conservation strategies that would pay off financially as well as environmentally. However, we do not have to wait for solutions to these more intransigent problems to promulgate some very simple and valuable Permaculture solutions into our communities.

For instance, the use of swales (contour ditches) helps direct and store water in the ground, reducing runoff. For the average homeowner, this means less water is needed for the garden. If used on farms, swales can help reduce the amount of irrigation, can help trap and store precious water in dry years, and provide easily maintained runoffs during unusually wet years. And on a large scale, swales will be crucial in helping to replenish ground water supplies, especially our precious aquifers.

Another useful Permaculture method is water catchment. Rainwater can be captured from roofs and stored in barrels or tanks, or it can be caught up in a series of ponds and used for a variety of purposes (aquaculture, irrigation). “Graywater” (drained water from kitchen sinks and showers, for example) can be directed into reed beds to filter out the impurities, and then used for gardens, showers, toilets, and washing clothes.

Implied in my mention of graywater systems is the use of Permaculture techniques for remediation of severely polluted water. Although not affiliated with the Permaculture movement, biologist John Todd’s “Living Machines” use natural methods to take the toxic water from industry and turn it into usable water once more, and the same principles can be used on a small scale as well. The idea is simple to grasp (though labor-intensive to start with): you take the tainted water and filter it through a series of reed beds and ponds, and you keep building more beds and ponds until you have a destination pond where fish and a variety of plants are able to survive. I believe that such systems will be an integral part of our sustainability strategies for the future.

Perhaps the greatest contribution of Permaculture to water management is its flexibility. Small and large scale water management systems can be designed to account for the most likely precipitation or water damage scenarios (short of natural disasters like tsunamis or category 5 hurricanes, obviously), and in such a way as to conform to the specific and unique conditions of a specific property. The Permaculture approach to water management will also save money for home and land owners, no matter how small or large the given area. In addition, and most important, Permaculture solutions are all about working with nature. A world filled with well-designed water systems will help repair the damage our civilization has inflicted upon the Earth, while simultaneously insuring our survival.