May 22, 2015

Category: News

M&A’s Gary Woodard will be giving a plenary talk on at the joint conference of the Universities Council on Water Resources (UCOWR) / National Institutes of Water Resources (NIWR) / and Consortium of Universities for the Advancement of Hydrological Sciences, Inc. (CUAHSI). The conference will be held at the Green Valley Ranch Resort in Henderson, Nevada, from June 16–18; Woodard’s talk is the morning of the 18th. The theme of the 2015 conference is “Water is Not for Gambling: Utilizing Science to Reduce Uncertainty.” Woodard is a past president of UCOWR, the conference organizer.

His talk is entitled “Causes and Consequences of Declining Municipal Demand: An Unexpected Water Resource Challenge.”


Western water supplies are under siege, as prolonged drought, scant snow packs, receding reservoirs, rampant groundwater overdraft, and devastating forest fires take their toll. The sense of urgency is deepened by stories about the challenges of supplying ever-increasing water demands. Many articles describing growing populations and sprawling metropolises appear to reflect the belief that desert cities are inherently unsustainable.

While supply uncertainties abound, the reality of water demand is very different. Rather than struggling to meet growing water demands, many western water providers have been surprised, perplexed, and even challenged by declines in demand. The USGS recently released Estimated Use of Water in the United States in 2010. The report documents how growing water use outstripped population from 1950 to 1970. But then water use plateaued for a decade, and has declined briskly ever since. Between 1980 and 2010, we managed to support 85 million more people and a growing economy while reducing water use by 57 billion gallons per day. It’s both a phenomenal success story, and a well-kept secret.

While the declines are both wide and deep, occurring in municipal, industrial, agricultural, and power sectors across the U.S., this presentation addresses efforts to model and forecast municipal demand in the Southwest. Declines appear to be nearly universal, to occur in both indoor and outdoor demand, and typically exceed population growth, resulting in utilities delivering less water to more people.

Because few utilities foresaw or planned on declining demand, a number of issues have arisen, including: fiscal consequences such as inadequate revenues; operational issues triggered by increased water age, inadequate residual disinfectants, and DBPs; planning challenges such as timing of system expansion and calculating waste water system capacity; and perception issues, such as backlash against conservation programs when declining demand triggers rate increases.

Detailed analysis has revealed an array of factors driving down indoor demand, including   voluntary ENERGY STAR and WaterSMART standards for appliances and fixtures, and state-enacted mandatory efficiency standards. Outdoor demand has also dropped, reflecting the declining appeal of turf and backyard pools and a growing interest in sustainability. In rapidly growing areas, average residential water demand has been reduced by the addition of new, highly water-efficient homes to the housing stock. Shifting household demographics also are impacting demand, in complex ways. Water demand is no longer tightly tied to population, economic output, or quality of life, and the downward trends are expected to continue through the end of the decade and beyond.

Don't forget to share this story!