Well, thank you, Kerri Ann. It’s a great pleasure to be here this afternoon with you and Under Secretary Novelli and Ambassador Hattie Babbitt. And it’s a pleasure to bring greetings from President Obama to all of the participants in this event. I think it’s an exciting event. It’s an important event. And I applaud everybody who came together to make this event happen.
The theme of the meeting today, of course, as everybody knows, is the global water challenge and the role of innovative technologies in addressing water and sanitation issues. I want to spend a few minutes on three points that provide some context for those efforts. First one is the relationship between water stress and climate change, the second is the water-energy nexus, and the third is how sustainable water resource management and innovative science and technology can really make a difference in the domain of these challenges.
Now, climate change is exacerbating many of the challenges related to water in the United States and around the world. I’m going to mention here six specific aspects of climate change that have significant impacts on the natural cycle that governs the global and regional supplies of fresh water. Those impacts, of course, do vary by region, but in general, in a warming world, we can expect shifting circulation patterns which together with the associated uneven warming and dissociated uneven evaporation are altering the geographic distribution of precipitation.
Secondly, more moisture in the atmosphere overall, leading to an increase in the fraction of precipitation that occurs in heavy downpours, is leading to increased losses to storm runoff. Third, more mountain precipitation falling as rain rather than as snow is reducing snowpack and thus reducing runoff available through the summer and fall. Fourth, earlier melting of mountain snowpack in the spring is also leading to reduced runoff through summer and fall. Fifth, the temperature-induced shrinkage of the mountain glaciers that feed many of the world’s rivers is putting their flows at risk. And finally, increased loss of water to evaporation from soil, from lakes, from reservoirs, and from rivers, is resulting from the higher overall temperatures.
Those impacts are imposing significant stresses on the water system, including slower recharge rates for groundwater, reductions in available surface water for human use, increased intensity of flood events in some regions and intensified droughts in others, and reductions in water quality that accompany many of these other phenomena.
In short, climate change impacts are projected to create a triple whammy of effects on the water system: not enough water in some regions in some time of year, even as global average precipitation increases; too much water in some regions and some times of year in the form of increasingly damaging floods; and finally, substantial water quality and sanitation challenges that further affect fresh water supply. And that’s just the supply side. We can also talk about demand.
As demand for water rises, its major use categories compete for a declining supply within any given water region. Those major categories include agricultural uses, mainly irrigation which is by far the largest user of water in agricultural regions; industrial uses, such as power plant cooling; and municipal uses, such as showering, running dishwashers and washing machines and watering lawns. Importantly, these uses need to be balanced with the need to preserve sufficient remaining flows in the environment to maintain ecosystem health and the associated ecosystem services. In an ideal world, all of these demand side factors should be considered in an integrated context with supply issues and with sanitation and treatment questions. That’s a tall order.
I want to focus on one crosscutting piece of the picture, a piece that is illustrative both of the complexity of the matter and of the possibilities for progress – namely, the intersection of water and energy. One part of that intersection is the way the energy technologies on which the world and the United States still depend for more than 80 percent of their primary energy supply, namely the fossil fuel technologies, are driving the climate change problem that is affecting water in the many ways I’ve already described.
The other two parts of that intersection are water for energy and energy for water. Water for energy includes, as the under secretary already mentioned, not only water for hydropower, but also the water requirements of fuel production and reclamation after production; the water requirements of fuel processing, of fuel transport – for example, in the case of slurry pipelines – for power plant cooling; for power plant maintenance, including even washing the dust off of solar collectors; and ultimately, for carbon dioxide capture and sequestration.
We need to pay more attention to optimizing the fresh water efficiency of all of these energy supply processes, taking advantage of new technologies, including those that allow for the safe and productive use of nontraditional water sources such as brackish water and industrial and municipal wastewater.
The other side of that coin, energy for water, includes the energy requirements for pumping ground water to the surface; for long-distance transport of water, including over mountain ranges in water projects; for treatment of sewage and other forms of wastewater; and for desalination of brackish and ocean waters. Here too, we need creative new approaches in order to increase the efficiency of water treatment and distribution systems, and to put to productive use wastewater from energy operations and waste heat from power plants and industrial processes.
Foundational to achieving all of those aims is the need to improve access to and exchange of water data and information, including better modeling of the hydrologic cycle to include the impact of human decisions about water use. A coordinated push with the ingredients I’ve indicated could halt the vicious circle of inefficient energy use that exacerbates inefficient water distribution and treatment systems, which in turn requires more energy and places even more demands on declining fresh water.
In place of that vicious cycle, we can imagine a virtuous one in which water-efficient energy sources support energy-efficient water delivery and treatment, complemented by innovative techniques for reducing wastewater creation, and for matching water quality to the requirements of different uses.
This of course brings me to the theme of this event, which is all about spurring innovation in science and technology for energy-efficient water sanitation and treatment, and for safely exploiting nontraditional sources of water around the world. The companies here today are bringing forward groundbreaking techniques for getting the most out of the water we’ve got, and I couldn’t be more enthusiastic about endorsing that idea. The challenges in this domain are of course very large.
To use one example from desalination – that is, desalting – the energy needs of current desalination technology as applied to sea water are between 12,000 and 18,000 kilowatt hours of electricity per million gallons of fresh water produced. Today, a sea water desalination plant is being built in the state of California near San Diego that will operate, within that energy range, capacity of about 50 million gallons a day or 55,000 acre feet per year. That output corresponds to the urban water needs of about 250,000 Californians. That is already no small feat. But put it in the context of California’s total energy demand, you would need 65 such plants to meet half of the urban water demand in California. And you would need – excuse me – an additional two gigawatts of base-load electricity generation capacity to feed the electricity needs of those 65 desalination plants.
That example makes clear that we need more innovation in the development of desalination techniques like the exciting brackish water desalination prize that I understand Chris Holmes and USAID will be unveiling later today. It also makes clear that we will need additional options and alternatives besides desalination, much like our clean energy efforts and all-of-the-above strategy as required in this case – a strategy grounded in integrated, sustainable decision making at regional scales in the context of a changing climate.
With that, I look forward to learning about exciting breakthroughs that this event will surely generate, and I thank you again for the opportunity to take part. (Applause.)