AWRA Colorado 2008 Symposium

April 18th, 2008
Mount Vernon Country Club, Golden Colorado
Summarized by Steve Smith

The AWRA Colorado Annual Symposium was held at the Mount Vernon Country Club on April 18th. The symposium was titled “Water, Energy, and Climate Change,” and was a great day of information sharing and networking for Colorado water professionals. Justice Greg Hobbs and Brad Udall opened the symposium as the keynote speakers (Figure 1). Speakers included consultants, scientists from federal agencies, non-profit organizations, universities, and municipalities. They provided a nice cross-section perspective on climate change and its effects on Colorado’s water resources.

Figure 1. Keynote Speakers Brad Udall and Justice Hobbs

Discussion included the mechanics and predictions associated with current climate change models, climate change’s effects on municipal supply, implications on energy and the environment, water quality and coal bed methane production, conservation efforts, and water supply management techniques to deal with effects of climate change. The morning discussion regarding climate models included the following main points.

• Colorado temperatures are predicted to increase by 3 degrees Fahrenheit by 2025 and 5 to 9 degrees Fahrenheit by 2100.
• There is currently no good projection for effects on precipitation, but wetter winters and dryer summers are likely in Colorado.
• Runoff will come earlier to Colorado rivers, and the peak annual runoff will shift from its current date in mid June to peak in May.

One of the afternoon breakout sessions focused on the effects on existing supply, and the potential management strategies to cope with climate change. M. Patrick Wells, a project engineer with Colorado Springs Utilities, discussed one of Colorado Springs Utilities’ current management techniques – aquifer storage and recovery (ASR). He explained that ASR has been used in the United States since the 1960s, and that there were approximately 70 active ASR systems in the U.S. in 2005. The first deep well ASR system in Colorado was implemented in the 1990s. Colorado Springs’ ASR system treats water at the McCullough treatment plant prior to injection to the Denver Basin Aquifers. Municipal parks and schools are currently utilizing non-potable water from the city’s ASR system for irrigation. The ASR system currently has a capacity of about 4,000 acre-feet per year with two wells. Their Arapahoe Aquifer well has an injection capacity of about 450 gpm, and a withdrawal capacity of about 600 gpm. Their Denver Aquifer well has an injection and withdrawal capacity of about 75 gpm. Colorado Springs Utilities’ ASR system is a good example of conjunctive use of surface and ground water, which will help the city manage its water supply through future dry periods.

A panel session on the challenges associated with climate change was held in the afternoon to wrap up the symposium (Figure 2). Nolan Doesken (Colorado State Climatologist) moderated the panelists: Joe Barsugli (NOAA climate modeler), Klaus Wolter (NOAA climate modeler), Levi Brekke (U.S. Bureau of Reclamation climate modeler), and Eric Kuhn (Colorado River Water Conservancy District general manager). Several interesting questions were raised by the audience. There was discussion regarding the cause of decreased runoff being projected by climate models with increased temperatures, even when precipitation is held constant. Climate modeling panelists explained that evapotranspiration is an exponential function of temperature, causing much greater water losses from watersheds even with constant precipitation.

 

Figure 2. Afternoon Panel Session Participants

The panelists explained that water vapor is the most important (more so than burning fossil fuels) factor in climate change, and increases temperature by trapping infrared radiation. An interesting point was made by another audience member that global warming and cooling has occurred in the past, including a cooling period from the 1940s to the 1970s. The panelists confirmed that there was a minority opinion during this time period that there was global cooling, and that it was caused by increased clouding associated with pollution from industrial rebuilding following World War II. Finally, the panelists spent a few minutes discussing what types of projects will be needed in the future to deal with the effects of climate change. Some examples of projects that were suggested included municipal utilities planning for rising sea levels (e.g. San Francisco and Boston).

The symposium concluded with one of the most heavily attended hors d’ouevres and cash bar receptions of recent years. The reception provided the symposium attendees a chance to mingle and network with their fellow water resource professionals. The process of planning for next year’s symposium will begin soon, so please provide any comments on this year’s symposium or suggestions for next year’s symposium. Please send your comments/suggestions to steve.smith@mwhglobal.com.