Secretary of the Interior Ken Salazar on December 12 announced the release of a study – authorized by Congress and jointly funded and prepared by the Bureau of Reclamation and the seven Colorado River Basin states – that projects water supply and demand imbalances throughout the Colorado River Basin and adjacent areas over the next 50 years. The Colorado River Basin Water Supply and Demand Study, the first of its kind, also includes a wide array of adaptation and mitigation strategies proposed by stakeholders and the public to address the projected imbalances.
The average imbalance in future supply and demand is projected to be greater than 3.2 million acre-feet by 2060, according to the study. One acre-foot of water is approximately the amount of water used by a single household in a year. The study projects that the largest increase in demand will come from municipal and industrial users, owing to population growth. The Colorado River Basin currently provides water to some 40 million people, and the study estimates that this number could nearly double to approximately 76.5 million people by 2060, under a rapid growth scenario.
“There’s no silver bullet to solve the imbalance between the demand for water and the supply in the Colorado River Basin over the next 50 years – rather, it’s going to take diligent planning and collaboration from all stakeholders to identify and move forward with practical solutions,” said Secretary Salazar. “Water is the lifeblood of our communities, and this study provides a solid platform to explore actions we can take toward a sustainable water future. While not all of the proposals included in the study are feasible, they underscore the broad interest in finding a comprehensive set of solutions.”
Authorized by the 2009 SECURE Water Act, the study analyzes future water supply and demand scenarios based on factors such as projected changes in climate and varying levels of growth in communities, agriculture and business in the seven Colorado River Basin states of Arizona, California, Colorado, New Mexico, Nevada, Utah, and Wyoming.
The study includes over 150 proposals from study participants, stakeholders and the public that represent a wide range of potential options to resolve supply and demand imbalances. Proposals include increasing water supply through reuse or desalinization methods, and reducing demand through increased conservation and efficiency efforts. The scope of the study does not include a decision as to how future imbalances should or will be addressed. Reclamation intends to work with stakeholders to explore in-basin strategies, rather than proposals – such as major trans-basin conveyance systems – that are not considered cost effective or practical.
“This study is one of a number of ongoing basin studies that Reclamation is undertaking through Interior’s WaterSMART Program,” said Assistant Secretary for Water and Science Anne Castle. “These analyses pave the way for stakeholders in each basin to come together and determine their own water destiny. This study is a call to action, and we look forward to continuing this collaborative approach as we discuss next steps.”
WaterSMART is Interior’s sustainable water initiative and focuses on using the best available science to improve water conservation and help water-resource managers identify strategies to narrow the gap between supply and demand. The WaterSMART program includes Reclamation’s Water and Energy Efficiency grants, Title XVI Reclamation and Recycling projects, and USGS’s Water Availability and Use Initiative.”This study brings important facts and new information to the table so that we can better focus on solutions that are cost effective, practical and viable” said Bureau of Reclamation Commissioner Mike Connor. “We know that no single option will be enough to overcome the supply and demand gap, and this study provides a strong technical foundation to inform our discussions as we look to the future.”
Spanning parts of the seven states, the Colorado River Basin is one of the most critical sources of water in the western United States. The Colorado River and its tributaries provide water to about 40 million people for municipal use; supply water used to irrigate nearly 4 million acres of land, and is also the lifeblood for at least 22 Native American tribes, 7 National Wildlife Refuges, 4 National Recreation Areas, and 11 National Parks. Hydropower facilities along the Colorado River provide more than 4,200 megawatts of generating capacity, helping meet the power needs of the West.
Throughout the course of the three-year study, eight interim reports were published to reflect technical developments and public input. Public comments are encouraged on the final study over the next 90 days; comments will be summarized and posted to the website for consideration in future basin planning activities.
The full study – including a discussion of the methodologies and levels of uncertainty – is available at www.usbr.gov/lc/region/programs/crbstudy.html.
The seven states in the Colorado Basin also reached an agreement on some basic principles in response to the study. From that agreement:
Additional Conservation and Reuse
The Basin Study recognizes that many municipal agencies in each state have implemented water conservation and reuse to meet the water needs of their growing populations and have incorporated comprehensive conservation programs into their planning to meet future demands. These conservation reductions are included in the forecast of future demands in the Basin Study. Municipal conservation can only be implemented step by step, providing a balance between water rates, demand elasticity, and demand hardening during droughts. Municipalities will continue to evaluate additional conservation and reuse, over and above what is already
reflected in the Basin Study demand scenarios, and implement necessary programs on a case by case basis considering local conditions.
In many states, significant agricultural conservation programs are already in place. Additional agricultural conservation, above that already included in the calculation of demands, will require significant additional investment. Agricultural water transfers are being implemented within the Law of the River, represented for example by forbearance of agricultural water use, and new transfers are under evaluation in many states. Many of the states are also exploring alternatives to permanent agricultural transfers, and these types of alternatives are being further analyzed and implemented. Only projects that actually reduce consumptive use will reduce the imbalances between future supply and demands. This Basin Study identifies additional conservation and transfer opportunities that will be considered by entities as appropriate through
local and/or state measures. While these local and state programs will offer a partial solution in some areas of the Basin, they may be, in many cases, problematic because much of the water diverted for use within the Basin returns to the river or a tributary for use by others downstream.
Water banking has been ongoing in the lower Basin for many years. A number of water banking options were submitted for consideration by the Basin States and Reclamation. A representative water banking option was included within the Basin Study to conceptually explore water banking. This option demonstrated that there are a number of legal, policy, and institutional barriers to implementing an Upper Basin water bank, however, the benefits associated with this option clearly demonstrate the need for additional exploration and analysis of this and similar concepts.
There are many watershed and regional solutions already being implemented and explored by the states and water agencies. For example, the states and water agencies have jointly been funding weather modification pilot programs for over five years as well as land and vegetation management options. All of these regional solutions are outlined in the Basin Study. The Basin States and relevant water agencies are committed to evaluating and implementing programs and options that have the greatest potential to yield additional supply. Although generally observed to be effective, the potential to generate additional water can vary
significantly from year to year, and it is often very difficult to quantify the additional amounts of water generated at particular locations within the river system. Accordingly, regional implementation of these options would likely need to be used to augment the river on a Basin wide basis.
Desalination and Importation Solutions
The large demand and supply imbalances projected at the latter part of the planning horizon can realistically be met only with implementation of a variety of options and strategies. Of the options analyzed, only large scale desalination and importation projects provide the reliability and quantity of water necessary to meet many of the plausible projected supply/demand imbalances. Future population growth in the Basin, the uncertainty of the reliability of the Colorado River supply and long lead times for implementation of projects, dictate that the Basin States and the Federal Government must start evaluating options for developing such project(s) immediately. For example, permitting and construction of large scale desalination projects may take 20 years or more before the projects become operational. The Basin States, in cooperation with appropriate Federal agencies will form a partnership to immediately begin developing a process to consider feasible options for developing large scale desalination and/or importation project(s), with the goal of having such project(s) in operation before the end of the planning horizon (by 2060).
Modification to the operations of Lakes Powell and Mead was implemented in 2007 through the “2007 Guidelines” and will be effective through 2026 with re-consultation to occur no later than 2020 or if Lake Mead reaches an elevation of 1,025 feet. The Basin Study does not contemplate any changes to the 2007 Guidelines. Within the context of the 2007 Guidelines, Basin States’ representatives will begin discussions of additional measures or approaches to be
taken at a Lake Mead elevation of 1,025 feet.
The Basin Study has again demonstrated to Reclamation and the Basin States the great interest in the future of the Colorado River by a wide variety of stakeholders—tribes, recreational entities, power providers, environmental organizations and conservation groups. As work continues following the completion of the Basin Study and based on its recommendations, the Basin States and Reclamation will continue to work with key stakeholders to explore solutions.
The Basin Study provides tools for water resource planning for the Colorado River Basin. The Basin States will work with Reclamation to evaluate progress regarding consideration of options listed in the Basin Study, evaluate the ability to use the tools developed for the Basin Study, and update water demands and supply scenarios on a five-year time frame. In addition, the Basin States will work with Reclamation to support improvements in the modeling and analytical tools used in the Basin Study and the information developed to support those tools, including those improvements specifically described in Appendix C5 of Technical Report C – Water Demand Assessment.
The Basin States will work with local, state, and federal representatives, and a wide array of diverse and interested stakeholders, to obtain funding to aid in the assessment and implementation of the above listed initiatives.