The Limits of Conservation and the Real Water/Energy Nexus: A Systems Approach
AWRA Colorado Section, October 27, 2015
Bill DeOreo, P.E.
President and Principal Engineer
Aquacraft Inc. Water Engineering and Management
Conserving water is unquestionably a good thing to do, but there are limits to how much water can be conserved in
an urban system without causing significant degradation to the economy or quality of life. For all practical purposes
even with good conservation it will take an average of ~100 gphd to supply residential users in the South Platte
Basin with domestic (indoor) water. The same amount of water will be required for landscape uses bringing the
total to 200 gphd or 70 gpcd. Public irrigation and ICI uses will add ~67% to this demand. In times of emergency
short term rationing can reduce these demands, but in “normal” times this is the water budget that is needed to
supply the metro area. Using demand forecasting based on over 20 years of end use analyses Aquacraft has shown that conservation can reduce the total M&I demands by ~289,000 AF from the baseline projection, but this still leaves a gap of 114,000 AF between the conservation reduced demands. Furthermore, over time, the potential for additional long term savings will be reduced as modern technologies saturate the market.
This presentation discusses the various ways that have been put forward for closing the water supply gap, and
suggests that one option has been overlooked: use of cogeneration to generate distilled water from flows in the
South Platte River below the confluence of the Poudre River, and pumping this water back up to municipal water
distribution systems in the South Platte and Metro Basins. The key to co-generation is that it uses waste heat from
power generation systems to supply the thermal energy needed to perform the distillation. Using modern technology for distillation, such as multiple effect distillers (MED) between 0.1 and 0.3 million gallons per day of distilled water can be generated from each megawatt of installed power capacity. This means that it might be possible to generate between 100 and 300 MGD of high quality drinking water from polluted the South Platte flows. The total cost of this for energy is estimated to be ~$1.36/kgal, delivered. Finally, the paper suggests that the new designs of high temperature nuclear reactors, based on molten salt technology, could drive this entire system, and convert the South Platte water and power system into one that is more self-reliant and less dependent on carbon generating energy. It is pointed out that the prime site for piloting this concept is the Fort St.Vrain generation station, which was initially a 1000 MW nuclear plant. So, this option is really going back to rediscover technologies that were well developed in the United States, but were set aside.
Presentation available here.
Mr. DeOreo has been actively practicing water engineering since 1978 after receiving his Master Degree in Civil and Environmental Engineering from the University of Colorado, Boulder. He has worked both in the public sector and as a private consultant. His main interests are in development of innovative supplies of water for municipal uses, improving the yield of urban water systems through better water planning and management, integration of urban water uses into watershed analyses, and development of computer based applications to assist with water planning. Mr. DeOreo is a member of the Planning and Evaluation sub-committee of the AWWA Water Conservation national committee.
Mr. DeOreo has participated in urban drainage master planning projects, large water rights transfers and augmentation plans, raw water master plans and numerous water utility related projects such as leak detection, hydraulic modeling and rate studies. He has a broad understanding of the technical, environmental and economic issues involved with water resources in Colorado and the West. He has testified as an expert witness in Colorado Water Court.
Under his direction, Aquacraft, Inc. has concentrated it in the area of urban water management, and has created several innovative approaches to providing a more rigorous basis for analysis of water use. The most important of these has been the Trace Wizard system for collection and disaggregation of water use data via analysis of flow traces obtained from the customer water meter. This analysis technique allows precise information to be collected on how much water is devoted to each end-use by residential users, and in turn, allows water providers to collect baseline data for planning purposes and to assess the effectiveness of water conservation programs on an ongoing basis. The technique can also provide accurate information on the impacts of water conservation on customer demands.
AWRA Colorado Scholarship Recipient Student Presentations
Annette Patton is an MS student doing geoscience research with Dr. Sara Rathburn at Colorado State University. She graduated from Whitman College in 2013 with a major in Geology and a minor in Biology. After graduation, Annette worked as a teaching assistant for the James Madison University geology field program and for the Washington State Geological Survey. She began her graduate program at CSU in 2014.
For her Master’s thesis, Annette is researching debris flow initiation in eastern Rocky Mountain National Park. Following the extreme rainstorm in September 2013, numerous debris flows initiated on steep hillslopes throughout the northern Front Range. These mass movements posed serious hazards to people, infrastructure, and buildings. Annette’s research seeks to identify the primary site-specific controls on debris flow initiation and to better understand the frequency of debris flows in high-risk areas.
Krista Garrett is an MS candidate in the Geosciences Department at Colorado State University, advised by Dr. Ellen Wohl. She graduated from Whitman College in 2012 with a BA in Geology and a minor in Mathematics. After graduation, Krista worked for an environmental consultant in Seattle, WA for two years, before moving to Colorado to begin her graduate degree program in 2014.
At CSU, Krista is researching the effects of oil and gas development on headwater streams in western Colorado. Headwater stream channels are small features on the landscape and often overlooked by regulatory protections. These channels, however, are the first to respond to changes in water, sediment, nutrients, and contaminants, and are important for the overall functionality of the river network. This project investigates the impacts of energy development on headwater channels in the Piceance Basin of Colorado. Krista is seeking to identify streams with the greatest sensitivity to energy development based on underlying lithology, stream gradient, and proximity to development.
Denver Water – Board Room
Brown Bag Lunch and Networking at 12:00, Student Presentations at 12:15, Program at 12:30
Visit Denver Water’s website for directions to their main office
(the building outlined in red with the blue Denver Water symbol).
PLEASE NOTE ALTERNATIVE ROUTES DUE TO CONSTRUCTION ON 6TH AVENUE!
We will not be ordering lunch for this event. Please feel free to “brown-bag-it”