New Report From Water Research Foundation Studies Changes In Water Use Under Regional Climate Change Scenarios
While many climate change studies focus on the potential impact to water supplies, what might be the impact on water demand? And what might those changes in demand mean to water utilities? A new study by the Water Research Foundation (WRF), an internationally recognized leader in water research dedicated to advancing the science of water, provides the tools to help water utilities answer those questions.
The study is titled: “Changes in Water Use Under Regional Climate Change Scenarios” (project #4263). The full report and supporting materials, including a Webcast available on demand, can be found on WRF’s Website. This research project is also featured in the latest edition of Advances in Water Research magazine, which is free and available to the public.
This project studied anticipated water demand and use patterns under a range of climate change scenarios, categorized by specific customer class and industry sector, so that water utilities may better plan for and respond to changing water use patterns as a result of climate change. The report provides specific recommendations for water utilities and identifies key concerns and areas for additional analysis by region.
“A chief recommendation from this effort is that water utilities spend more time studying and modeling climate- and weather-induced water demand patterns,” explained Rob Renner, Executive Director of WRF. “By applying some of the analytical techniques demonstrated in this study, water utilities can gain a more thorough understanding of the importance of climate in shaping water demands relative to longer-term socioeconomic factors and the role that actual weather plays in influencing shorter-term demand variability. The resulting insights about demand may reveal important lessons and implications for both water supply operations and planning.”
A key element to the study was the development of six case studies involving WRF member utilities. These include:
- Colorado Springs Utilities
- Massachusetts Water Resource Authority
- Region of Durham (Ontario, CA)
- San Diego County Water Authority
- Southern Nevada Water Authority
- Tampa Bay Water
The case studies use a scenario approach to incorporating climate change projections into water demand modeling for their specific regions. The scenarios are designed to identify a wide range of model outputs in terms of temperature and precipitation.
Tampa Bay Water’s experience from participating in the study highlights the value of undertaking a climate change study that focuses on demand as well as supply.
“What was eye-opening for us was learning of the potential to experience hot dry periods,” said David Bracciano, Demand Management Coordinator, Tampa Bay Water. “Typically, what could potentially be our highest demand period is also a time of considerable rainfall that keeps irrigation use low. If we start to have periods of significant heat coupled with dry weather that will obviously spike demand. That is something we need to look at carefully in future planning and evaluation efforts. Many entities have looked at what happens to supply in the future but not the demand side. And this study opens up people’s eyes to different demand scenarios in the future.”
For the overall industry the study resulted in several principal conclusions spanning across several topics that are important to evaluating the potential effects of climate change on water demand. These include:
- Weather sensitive demands are prevalent and will be affected by climate change Weather-sensitive water demands exist in virtually all places in the country and account for a substantial portion of total municipal water demands in most regions and a majority of total demand in some areas and times of the year.
Evaluation of weather and climate impacts involves a host of technical modeling requirements, choices, and tradeoffs.
With regard to water use modeling, an over-riding conclusion is that only certain types of models, specifically those that contain and relate weather and climate indicators to water use, are relevant for evaluating the potential effects of climate change.
- Derivation and processing of climate model projections is a data intensive process. The identification and processing of suitable climate projections is the bridge between modeling the response of water use to climate and weather and the use of water demand models in assessing potential impact.
Climate projections and estimated demand impacts vary geographically.
The reconnaissance-level evaluation of regional climate change vulnerabilities and statistical estimation of demand impacts for six utilities suggest that future climate scenarios could lead to additional complications for water resources management.
A range of options could assist in adapting to demand impacts.
The case studies and regional assessments point to several possibilities for adapting to the consequences of climate-induced changes in water demand. Should they continue, some recent trends in patterns of water use, such as declining rates of per capita domestic use and shifts in allocations of water among competing uses, may in some regions counteract some of the additional pressures from warmer temperatures, less precipitation, and urban growth.
“Based on the results of the case studies, a major conclusion of this study is that changes in climate are predicted to vary both in magnitude and seasonally across the regions of the United States,” continued Renner. “The impacts of these changes on water demand will vary because of different geographical sensitivities of demand to climate and weather. The impacts on demand could be relatively large for some locations and relatively moderate or even minor for others. The point is that there is no way of discerning potential impacts without undertaking the types of analyses demonstrated in the case studies.”
About the Water Research Foundation
The Water Research Foundation is an internationally recognized leader in sponsoring research that supports the water community in holistically and cooperatively managing water from all sources to meet social, environmental, and economic needs. WRF’s research provides reliable and relevant solutions to the most critical challenges facing the water community today and into the future. Founded in 1966, WRF is a 501(c)(3) non-profit organization that has sponsored nearly 1,500 research projects and serves more than 1,000 subscribing organizations. For more information, visit www.WaterRF.org.
SOURCE: Water Research Foundation