Urban Water Demand Roundtable: Bringing Together the Best in Current Research and Applications
April 18-19, 2013 | Four Points by Sheraton Hotel | Tempe, Arizona
It is now widely acknowledged that falling water demands across most of North America by both residential and commercial customers represents a significant change in the nature of water use as experienced over the last several decades. This presents a variety of challenges and opportunities ranging from reduced pressures on water supplies, to increased revenue stresses for utilities, to the need for revised infrastructure standards. As a result, the water utility sector needs improved information on the causes of these declines in demands so that water resource, infrastructure, financial, water quality, and operations planning accurately anticipate possible future changes in customer needs. One possible source of this improved information are research partnerships between researchers working in universities and other academic institutions with professionals in water utilities that focus on both utility-specific and broader community and industry studies. One objective of this workshop is to facilitate these types of activities.
The primary theme of this event will be to improve communications among those involved or interested in water demand research in academic institutions, water/wastewater utilities, and consultant-managed projects. The workshop will be attended by approximately forty-five utility representatives, academics and consultants focusing on facilitating the exchange of ideas and experience among top academic and professional researchers. A key desired outcome of the workshop will be to identify research priorities and potential collaborations between different individuals and organizations.
Michael Hanemann, Arizona State University
Ray Quay, Arizona State University
Kerry Smith, Arizona State University
Dave White, Arizona State University
Conveniently located near Arizona State University-Tempe campus and Sky Harbor International Airport, Four Points by Sheraton Hotel is our partner in providing meeting space and lodging for workshop participants. Four Points by Sheraton provides free shuttle service to and from the hotel. Contact them at (480) 968-3451 to arrange a pick-up time.
Map to Hotel
1333 Rural Rd.
Tempe, Arizona 85281
Phone: (480) 968-3451
Thursday, April 18, 2013
- 8:00-8:30 Breakfast
- 8:30-8:45 Welcome
- 8:45-10:30 Session I: Why Are We Here? Why Falling Per-Capita Water Demands Are A Critical Issue for Utilities, Academia, and the Public at Large.
- 10:30-10:45 Break
- 10:45-11:30 Who We Are: ‘In a Nutshell’ Summaries. Three Minute Presentations by Participants’ of Their Interests and Research Work
- 11:30-1:00 Lunch and Keynote Speaker I – Maureen Hodgins, Water Research Foundation [presentation]
- 1:00-2:15 Session II: How Low Can You Go? Part A – Research Related to Changes in Indoor Use.
- 2:15-3:30 Session III: How Low Can You Go? Part B Research Related to Outdoor Residential Use
- 3:30-3:45 Break
- 3:45-5:15 Session IV: Compare and Contrast: Trends From Across the West
- 6:00-7:00 Reception Z’Tejas. Charter bus departs at 6:00pm. Ray Quay will recap day one. Engage in participant discussion of the day’s activities and areas of collaboration. Looking ahead at day two. Participants will be asked for their input.
- Z’Tejas Dinner. Charter bus departs restaurant at 9:00pm
Friday, April 19, 2013
- 8:00-8:30 Breakfast
- 8:30-10:00 Session V: Building a Better Mouse Trap: Improving the Way We Model Future Water Demands
- 10:00-10:15 Break
- 10:15-12:00 Session VI: In the Long Run We’re All Dead: Discerning Short-Term Cyclical Trends from Medium and Long-Term Structural Changes
- 12:00-1:30 Lunch and Keynote Speaker: Kenneth Gillingham, Assistant Professor of Economics, Yale University – Lessons to be Learned from Industry: Demand Research and Modeling [presentation]
- 1:30-2:30 Session VII: What’s on the Laundry List: Roundtable Discussion on Research Priorities and Information Exchange
- 2:30-3:30 Event Post-Mortem and Organization Planning. Discussion on the value of the workshop and possible follow-up events.
Demand Roundtable Research Needs and Potential Research Collaborations
Based on discussions at our spring 2013 Urban Water Demand Roundtable, below are fifteen research needs and potential research collaborations. Please review and suggest any changes you feel are appropriate, or add other items of research you think were missed. Please send your suggestions to Ray Quay, who will compile a final document. This will be part of an online report we will prepare in addition to the current website documenting the roundtable event.
- Profiles of Residential Water Appliances and Fixtures
- Evaluation of Policy Making
- Dynamics of Industrial Demand
- Economic Efficiency of Non Residential Water Use
- Understanding Outdoor Water Use
- Demand Trends of New Housing
- Effectiveness of Drought Response
- Real-Time Water Use Decision Making
- Getting the Word Out
- Landscaping Change in Existing Housing
- Data Sharing
- Climate Change Impact on Demand
- Possible Demographic Trends and Impact on Demand
- Deeper Understanding of the Economics of Demand
- Emerging Conflicts
Understanding how low indoor water use can go and how fast we can approach this low point is important for understanding the future of indoor water use. It is clear we are approaching minimum use on the technology side, but we do not clearly understand the rate at which these technologies are being adopted in existing and new homes. Creating local and national profiles every one or two years of existing water-use appliances and fixtures that exist within various residential types would help us begin to better understand at what rates these fixtures are being incorporated into homes. This would require development of a standard survey instrument and implementation method, as well as funding to implement the survey on a national basis with options for adding higher local resolution for different regions. Tampa Bay Water has had experience with such a survey, which could be used as an initial guide.
Just as we cannot predict the future of water supply or demand, we can also not predict the future success or impact of water demand management policies. Recent research has shown that some water demand policies, such as alternate days for irrigation, sometimes do not result in reduced water use. Given policy making is an experiment, one thing we are lacking is experimental evaluation as part of our policy making. Each time we implement a water demand strategy, we are conducting an experiment, but rarely do we include an evaluation of the results. Conducting an unbiased experimental evaluation of policy results, with distribution of these results, would benefit the practice of water demand management. Two approaches to this were discussed. 1) Before a policy is implemented, develop an evaluation methodology to be applied to demand management strategies after a set period of time. This could be done by the utility and then published in a journal article, on their website, or in a public report. 2) Solicit existing research institutions with an opportunity to evaluate the policy. This would require some mechanism to provide utilities with a list of potential research institutions that would be interested in such research. Partnerships for such evaluation could be formed around funding opportunities.
Water demand research has been primarily focused on residential water use because for most communities residential demand makes up the largest portion of their total demand. But in some communities, such as Chandler and Tempe, Arizona, non-residential water use is a significant portion of their demand. Unlike in the residential sector, few standards exist on how to collect data on non-residential water use and the internal water infrastructure of non-residential water use. More research about the primary drivers of commercial and industrial water demand, particularly what aspects of demand may be common among various sectors of commerce, is necessary. This research may perhaps be based on the North American Industrial Classification System though there was some discussion that there may be unique aspects of this for different regions and in some cases there is a high variability of use within a single class.
Water is a key resource necessary for most types of economic development. Yet little is known about the water needs of different industrial/commercial sectors and the role water quality, cost, and dependability play in locational decisions. Few (if any) metrics exist for measuring the water efficiency of industries in terms of economic output, preventing communities from assessing the water resource costs versus economic benefits of different economic development strategies. An understanding of how water resources relate to economic development and some analysis of per gallon efficiency, in terms of jobs or economic output, would be useful.
For most communities, outdoor water use, particularly in the residential sector, represents a significant portion of total water demand. Understanding how residential landscaping and other activities, such as pools, relates to this demand would be useful in understanding the potential for future reductions in outdoor water use. Gathering site specific information about their customers’ yards can be time consuming and outside the capabilities of most utilities. The use of high spatial resolution satellite data to identify and quantify land cover on individual lots may provide a lower cost, higher accuracy option for collecting such data. The potential for use of such data in various climate zones should be explored.
Over the last 20 years, per capita water demand in most communities has been declining. This is due in part to changes in outdoor landscaping trends for new homes, such as changing lot sizes and landscape preferences in new houses. However, the factors and events that trigger these changes in new houses are not well understood. Research is needed to identify factors and events that initiate such changes in density and land cover and what the potential future is for such changes, i.e., the possibility that these trends will flatten out or reverse.
A number of communities (e.g., Denver, Colorado Springs, Los Angeles, and Atlanta) have experienced severe drought conditions that have triggered aggressive water use reduction efforts. However, little information is available about how successful these efforts have been in the short term and long term. It is not also well understood how each of these drought demand management efforts integrate with short and long term supply management strategy. Case study research would be helpful in understanding the success or failure of such programs and how they strategically fit into a broader water management strategy.
There is some evidence in the power industry that providing real time information to customers about resource usage results in a reduction of total use. This needs to be explored for water and involves several questions. How should real time information about water usage be delivered to the customer? Given that water consumption is different from energy consumption, how would customers respond to real time consumption information to reduce their water use? What does real time in terms of water consumption mean on an hourly, daily, weekly, monthly basis? How prevalent among utilities is the need to reduce peak demand? There is a need for more experimental work in this area in order to answer these questions and evaluate the utility of real time water consumption information as a demand management strategy.
We learned a number of things from the results of academic and professional research at the workshop. There was discussion about broadening the audience for some of the more salient and relevant research results. What is the best way to disseminate this information to others in the industry and academic community? Academic researchers do not publish as much in professional journals because it does not benefit them academically. Professionals do not frequently read peer reviewed journals and there is little incentive for public sector professionals to publish their work in professional journals. How do we encourage more publication of research and project results in professional journals?
In the more arid climates of the US, we heard about people converting from wetter (mesic) landscaping to drier (xeric) landscaping. In some cases, cities have incentive programs to encourage people to remove turf, but there is some evidence that such conversions would have happened even without the incentive. We currently have little information about what motivates people to move from mesic to xeric landscaping. Are there trigger events that cause such events, such as a home sale, or a neighbor changing their landscaping? What is the rate of market penetration of such conversions and what drivers may be an indicator of this rate of change? Are there economic forces influencing such decisions and, if so, what role do (could) incentives play in these decisions?
Much of the academic research relies upon current and historical water use at the parcel level. But these data can be hard to come by for a variety of reasons including historical records of water use not being available or reluctance to release such data. What are the barriers to making such data sharing happen? What can academics and industry do to facilitate such data sharing? Would standard data sharing and data security agreements help? Would published case studies where such data sharing benefited the utility help?
To date research on climate change and the impact of drought on demand is just beginning to scratch the surface. Kiefer’s study (et al, 2013) shows such impacts likely are not linear and may vary from at least region to region, and perhaps from utility to utility. Many questions remain. How are utilities incorporating climate change in demand and supply? Are there differences between hot spells, long term drought, and potential climate change? Are we going to see macro-economic changes, such as shifts in growth rate, as a result of climate change? Are there operational issues related to water delivery that would be affected by climate change that affect demand? In the bigger, long-term picture, would a carbon tax be cost effective? Outdoor water use is a function of infrastructure (type of landscaping, pools, etc.) and local climatic conditions (temperature, solar gain, and precipitation over time) yet little is known about these relationships. Future potential climate change may result in increased temperatures and changes in precipitation which may change landscaping regimes; how and when would such changes affect outdoor water use?
GPCD and population growth are still the two primary drivers of total water demand. Much research has been proposed here on understanding future potential changes in GPCD, but we also need to anticipate what changes may occur in population growth. Could climate change result in shifts in population from, a) warmer/drier to cooler/wetter regions, b) coastal areas impacted by sea level rise and storms to inland communities? As world population growth rates peak, will growth rates also peak in the US and when might this occur? Research of these possible trends and their potential impact is needed.
Though we are exploring price elasticity for different groups and classes of customers, further questions remain. What are the appropriate metrics for income impacts (such as per capita income, ability to pay)? How are the metrics affecting price elasticity? What strategies make sense under various scenarios of change in rate structure, such as flattening? What is the willingness to pay for “special” things, such as water for the environment or projects that provide long term resilience to drought or climate change? Does where people come from and their experience with landscaping and rates affect their water use decisions? How do people perceive different rate structures and what is their perception of their own consumption?
A number of trends may have conflicting policies including community aesthetics and urban heat island resilience versus lower outdoor water demand and planting trees for shade versus decreasing outdoor water use. Demand lowered through conservation, resulting in less water moving through water pipes and sewer lines, may result in increased costs to managing water quality and sewer maintenance. Standards that are designed to insure adequate capacity for fire-fighting flows may result in lines being designed over capacity for normal water demands.