“Stationarity—the idea that natural systems fluctuate within an unchanging envelope of variability—is a foundational concept that permeates training and practice in water resource engineering.”1 However, as Peter Milly has observed, stationarity with respect to water resources is dead, as volatility in climate, precipitation and temperatures are causing wider fluctuations in available water resources. Water managers must now consider how to deliver and maintain water resources in this new order.
With the demise of the notion of stationarity within our industry, our reality is one of uncertainty and unpredictability. As such, we must be more innovative in our approach to water management, look beyond the traditional infrastructure-based projects and implement solutions that can handle the instability.
We can probably safely say that humans have never lived without impacting their local environment. This is particularly true as it relates to water resources. Some of the first large scale engineering works were dedicated to finding and delivering water to sustain human activity. Water projects were central to the Egyptians, the Minoans, the Romans, the Mayan, the Hohokam as well as a myriad of other civilizations. The fact that water is not always where we need it, when we need is a driving force in the supply-side driven, engineering-based water management philosophies that continue to be utilized today.2
Consumption is taking place on a canvas of an increasingly volatile natural supply of water. While for the first time in 50 years, water withdrawals for United States public supply actually declined, worldwide water consumption continues to increase, particularly as it relates to domestic and industrial water use. Over the coming century, these withdrawals are expected to rival the consumptive use associated with agriculture:
“A large increase in domestic and industrial water use is…obvious in the global trends…. Domestic water consumption is projected to more than double from ~280 to ~600 cubic kilometers per year (km3/yr) by the end of this century, while the increase in industrial water consumption is expected to be slightly milder from ~300 to ~550 km3/yr. Future irrigation water consumption…shows a much lower increase from ~1,400 to ~1,600 (±~200) km3/yr over the same period.”3
Lost Packages
With our ever-increasing ability to quantify the influence of climate volatility on water resources on both a global and human scale, we can see the impact of changing environmental conditions — and the news is not good. These conditions will result in significant water deficits for certain areas. The old real estate adage is true for water resources — location matters.
As such, geospatial context will become increasingly important to water managers.6 This is particularly important in places that rely on snowmelt to supplement water supplies during the drier summer months. In the northern hemisphere, most water needs can be met with a combination of natural rainfall and snowmelt. But these conditions are not uniform across the hemisphere. Recent research has evaluated the impact of rainfall and snowmelt at a basin scale, identifying which watershed basins are currently, and when subjected to the influences of climate variability, will be, incapable of meeting demand with natural precipitation. Not surprisingly, much of California suffers from this condition today, as does Spain, Portugal, the Middle East and South West Asia.
As climate changes, the impacts of deviations from “normal” precipitation patterns emerge as increasing risks to those basins. The result is that “decreases in spring and summer rains pose the risk that some basins that currently have enough rainfall to meet human water demand…may transition to having unmet demand by 2060…even without considering possible future increases in human demand.”7
In areas where natural precipitation is projected to decline as a result of climate volatility, we will increasingly look to groundwater as a means of offsetting those deficiencies. While groundwater can be replenished, a recent study suggests that this replenishment occurs at time scales that are decidedly longer than human lifespans. In fact, only 6 percent of the water in the upper two kilometers of the Earth’s crust has been replenished in the past 50 years.9 Tapping that resource then means drawing on reserves that are largely non-renewable at human time scales.
Technology Delivers
The volatility of water supply and increasing water demands are projected to place us in an extremely vulnerable position. The Blue Water Sustainability Index (BlWSI) — an indicator of humanity’s use of available surface water resources (precipitation dependent) and groundwater resources (time dependent)—is expected to worsen throughout the coming century.
Compounding this condition, Milly notes: “The world today faces the enormous, dual challenges of renewing its decaying water infrastructure and building new water infrastructure.”10
When considered alongside other conditions within the utility — the destruction of revenue as a result of conservation, and the sense of overall financial malaise — it’s unlikely that our utilities will have the financial resources to meet Milly’s dual challenges.
A new way of thinking based on demand-side management closely coupled with revenue assurance is required to survive in the new water reality. By employing new data management technologies, utilities can find revenue lost in the data, become more proactive in system operations and fully utilize their existing infrastructure investments.
Big data technologies allow utilities to continue to deliver high quality, resilient service — despite the weather.
Trevor Hill is a co-founder of both Global Water and FATHOM. He serves as chairman and chief executive officer. Prior to that, he co-founded Algonquin Water Resources of America in 2003. In 1994, he co-founded Hill, Murray & Associates, a design-build firm specializing in the construction and operation of water reclamation facilities in British Columbia and the Canadian Arctic. Hill retired from the Canadian Navy in 1994, after serving as an engineering officer and receiving the Gulf Kuwait Medal for his service in the 1991 Gulf War. He graduated from Royal Roads Military College with a degree in mechanical engineering in 1987. He attended the Royal Naval Engineering College in Plymouth, England, and completed his post-graduate studies in 1988.
References
1Milly, P.C.D., Betancourt, J., Falkenmark, M., Hirsch, R.M., Kundzewicz, Z.W., Lettenmaier, D.P., Stouffer, R.J., Stationarity Is Dead: Whither Water Management?, SCIENCE VOL 319 1 FEBRUARY 2008
2THE PAST, PRESENT AND FUTURE OF WATER SECURITY, FATHOM Drought Watch, Volume 1, Issue 20, 21 August 2015 (http://www.gwfathom.com/download/1589/)
3Wada, Y. and Bierkens, M. F. P., Sustainability of global water use: past reconstruction and future projections, Published 2 October 2014, Environmental Research Letters, Volume 9, Number 10, http://iopscience.iop.org/article/10.1088/1748-9326/9/10/104003
4AWWA, 2015 AWWA State of the Water Industry Report
5Ibid., Wada, Y. and Bierkens, M. F. P.
6WATER SCARCITY: LOCATION MATTERS, FATHOM Drought Watch, Volume 1, Issue 6, 15 May 2015 (http://www.gwfathom.com/download/1586/)
7Mankin, J.S., Viviroli, D., Singh, D., Hoekstra, A.Y., Diffenbaugh, N.S., The potential for snow to supply human water demand in the present and future. Environmental Research Letters, 2015; 10 (11): 114016 DOI: 10.1088/1748-9326/10/11/114016
8Ibid., Mankin, J.S. et al
9Gleeson, T., Befus, K. M., Jasechko, S., Luijendijk, E., Cardenas, M. B., The global volume and distribution of modern groundwater, Nature Geoscience, 16 November 2015 (advance online publication) http://dx.doi.org/10.1038/ngeo2590
10Ibid., Milly, P.C.D. et al.
11Ibid., Wada, Y. and Bierkens, M. F. P.
