Report: Large-Scale Water Pipeline Trend Threatens Western Water Supplies and Rates

Most projects fail to assess climate change impacts, water supply reliability and cost-effective alternatives, putting millions of people at risk of long-term water supply vulnerability

SAN FRANCISCO (June 20, 2012) – The growing trend toward large-scale water pipeline projects in the West could lead to water shortages and increased costs for the very communities that would pay for these expensive facilities, according to a report released today by the Natural Resources Defense Council. 

“The western water landscape has changed dramatically in recent years. When considering the water needs of growing populations, water projects of this scale cannot ignore the impacts of climate change and all the better, more sustainable solutions that exist,” said Barry Nelson, senior policy analyst at the Natural Resources Defense Council and one of the authors of the report. “Unfortunately, most of these pipeline proposals would rely on scarce water sources and overlook cost effective alternatives like water use efficiency.”

The report, Pipe Dreams: Water Supply Pipeline Projects in the West, reveals that a new generation of proposed pipeline projects lack adequate analysis of climate change, the availability of water, and energy use. More reliable, cost-effective alternatives such as water efficiency are rarely or inadequately assessed by the federal, state, local and private entities that propose most of these projects. The report examines 15 projects in Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming. 

Climate change is expected to decrease water available from both surface and groundwater sources in the West, particularly in the Colorado River Basin. The greatest concentration of pipeline proposals is in this Basin, with five proposals in recent years to divert nearly 700,000 acre-feet of water annually – roughly three times the annual water use of the city of Denver– from a river system that is already over-tapped.

The U.S. Climate Change Science Program has projected that the Colorado River Basin is likely to face a decline in runoff of 10-25 percent by mid-century as a result of climate change. Our analysis showed that the Lake Powell (Arizona and Utah) and Narrows (Utah) projects have inadequately addressed how changes in precipitation, more frequent prolonged dry periods and higher temperatures could impact the availability of water.                                                                                                    

Several of these proposed pipelines would tap into groundwater basins in arid regions such as Texas, Eastern Nevada and the Mojave Desert. For example, the Cadiz Valley Project in Southern California proposes to extract up to 50,000 acre-feet of water per year – one independent estimate calculates that local groundwater recharge is only 5,000 acre-feet annually.

Most of these projects would also require a great deal of energy to pump water to distant users, further increasing carbon emissions, contributing to climate change. The proposed Santa Fe-Pecos Pipeline (New Mexico), for example, would climb nearly 4,000 feet in elevation to reach its destination. This is double that of the California State Water Project’s 2,000-foot lift over the Tehachapi Mountains—an extraordinarily energy-intensive water project.

While many new large-scale water project proposals raise a host of serious questions, there is also a growing number of water agencies such as the City of Los Angeles that are investing in water conservation, water recycling, groundwater clean-up and other tools to increase the efficiency of existing water supplies. These solutions may offer greater potential to meet the needs of western communities more cheaply and reliably with less vulnerability to climate change impacts.

NRDC recommends that local, state and federal agencies considering these pipeline projects improve their analysis of key issues. Some of the paper’s recommendations are:                                                             

  • New water supply projects should be designed to reduce, rather than increase, current water shortages.
  • Proposed pipeline projects should include a thorough analysis of: the reliability of water sources, projected climate change impacts, energy impacts, costs and alternatives, particularly water use efficiency. 
  • Projects should carefully analyze the potential for economic and water supply impacts on existing water users.
  • Energy for future pipeline projects should be provided through investments in renewable energy sources.

For more information about western water and this report, read Barry Nelson’s blog: