Home » Climate Change » Drought in California Part 4. The Potential to Procure Additional Ground and Surface Water

Drought in California Part 4. The Potential to Procure Additional Ground and Surface Water


This is the fourth post in my series Drought in California. In Part 1: California Climate and Drought I surveyed the current drought in California and climate projections for the future, finding that drought is projected to be the “new normal” climate in California. In Part 2: The Status of California’s Current Water Resources I found that California is already depleting both it’s groundwater and surface water resources. In Part 3: California’s Total Water Deficit I constructed an overall estimate of California’s future water deficit, concluding that it will be about 25.1 million acre-feet per year, about 39% of California’s current dedicated water supply.

In this post, I will begin to explore whether significant new groundwater or surface water may be available. There are three possibilities: groundwater, surface water, and desalination. At the beginning of each part in the series, I note that there are problems with the data and analyses I’m having to use. If you want to read more about the problems, see the introduction to the series.

The Potential to Procure Additional Groundwater

California has been blessed with significant groundwater resources. Maps of the state show that much of the state, even its desert regions, are underlain by groundwater deposits.Those maps should tell us something, however: California’s groundwater resources have already been discovered and mapped. As discussed in Part 2 of this series, the large groundwater basins have already been overdeveloped and are being depleted. Further, if future precipitation declines as projected, especially the snowpack, less water will be available to recharge the groundwater basins, causing their decline to accelerate. One may wish for the discovery of large, previously unknown, groundwater basins, but it seems unlikely.

Some locations (e.g. Santa Monica) have new treatment equipment that purifies potable water from chemically contaminated groundwater sources. In Santa Monica’s case the city once used water from the Charnock Subbasin, but had to stop when it became contaminated with MBTE. The new equipment is capable of removing the MBTE. Though good for Santa Monica, this does not really represent a new groundwater source, but rather the recovery of one that had been lost. (Santa Monica Public Works, 2015)

Figure 11: The Santa Monica Groundwater Basin, Showing the Charnock Subbasin. Source: Metropolitan Water District of Southern California, 2007.

Figure 11: The Santa Monica Groundwater Basin, Showing the Charnock Subbasin. Source: Metropolitan Water District of Southern California, 2007.

In addition, most of these groundwater basins are small. For instance, the Charnock Subbasin is part of the Santa Monica Basin. The safe natural yield of the entire basin is 7,500 acre-feet per year, and the Charnock Subbasin is a only a small part of the whole (See Figure 10). Thus, the increase in yield, though meaningful for Santa Monica, is not meaningful against California’s projected future water deficit of 25.1 million acre-feet per year. (Metropolitan Water District, 2007)

(Click on graphics for larger view).

Another possibility would be to purify brackish or saline ground water sources using desalination technology. Compared to ocean water, desalinating brackish water involves an additional limiting physical and cost factor: desalination leaves behind a concentrated brine residue. At the ocean, the brine can be diluted and discharged back into the ocean, which dilutes it even further. Because brine desalination tends to occur inland, disposing of the residue in an environmentally acceptable manner becomes a much greater challenge. Though methods exist, they are imperfect and costly. (Committee on Advancing Desalination Technology. 2010) Given that California is bordered on one side by the ocean, it seems likely that opportunities for ocean water desalination will be exhausted before desalination of saline ground water would be pursued. Ocean desalination will be discussed in the next post in this series.

The Potential to Procure Additional Surface Water

Another possibility would be to transport additional surface water to California. In 2012, the Governor proposed building additional infrastructure to transport existing water from the San Francisco Bay Delta to Southern California. This is precisely what the Central Valley Project and the California Aqueduct already do. There is already a 5 million acre-feet shortfall at the Delta, however, and the existing projects have already caused extensive environmental harm. Despite the severity of the current drought, opposition has prevented the proposal from advancing.

What about diverting water from untapped rivers and watersheds?

Figure 12: Four Rivers of the Klamath Mountains. Source: Google Earth.

Figure 12: Four Rivers of the Klamath Mountains. Source: Google Earth.

Near the coast of Northern California, the Klamath Mountains are the wettest region of the state, with some locations receiving 100 inches of precipitation per year. This has been an area of interest for decades. In fact, one of the original proposals for the California State Water Project went beyond what actually got built and included damming the Klamath, Eel, Mad, and Smith Rivers and shunting their water through a series of inter-basin transfers into the Sacramento River. (See Figure 11) The combined discharge of the rivers into the Pacific Ocean is about 26 million acre-feet, enough to meet California’s estimated future shortfall if almost all of the water were diverted. (Wikipedia, 2015a)

The project, however, would have required one of the largest engineering projects ever undertaken. In addition, it would have appropriated water from holders with senior water rights. The senior holders are Native American Tribes, and while diverting their water may have been politically acceptable in the early decades of the 20th Century, by the 1950s, it was not. And finally, it would have devastated the rivers, their watersheds, and the communities along them. The proposal was not acceptable, and the rivers were not dammed. Even Los Angeles, the proposed final recipient of the water, opposed the plan. (Wikipedia, 2015b)

Today, such diversion projects are received even more frostily than they were in the 1950s. In fact, these rivers are now under the management of the Federal Government in the National Wild and Scenic Rivers Program. Many states are removing dams from rivers, not adding them. Dam removal has even been planned for the Klamath River, where in 2009, the Federal Government and other interested parties agreed to remove 4 dams. The legal rights of Native Americans and of water rights holders are more firmly established than they were many decades ago. (Hanak et all, 2011, p. 117)

Could water from the Klamath Mountains be diverted to the rest of the state? Though the obstacles seem overwhelming, because of the severity of the crisis, one cannot definitively rule out the possibility. Even if the decision were made to proceed with such a project, however, it would take decades of legal wrangling, planning, and construction. Completion would come too late to prevent widespread disruption from water shortages. Thus, no matter what, diversion of the Klamath Mountain Rivers does not seem like a solution to California’s looming water shortage.

What about other rivers?

The rivers on the western slope of the Sierra Madre Mountains have already been fully tapped. On the eastern slope, the Owens River has already been tapped. The only other river of substantive size is the Truckee River. The river arises as the only outlet of Lake Tahoe, and it flows northeast through Reno, Nevada, to Pyramid Lake, Nevada. In an average year, the discharge of the river at Truckee, California is 681,496 acre-feet per year. But given that drought is projected to be the “new normal” climate in California, discharge in low water years may be more relevant. The average discharge of the Truckee River in the lowest quartile of years is 106,272 acre-feet per year, and the lowest year on record is a mere 23,465 acre-feet. Thus, even if all of the river’s water was diverted, it would make good less than 3% of California’s projected water deficit in an average year, 0.4% of the deficit in a dry year, and 0.09% in years similar to the driest one on record.

Figure 13: The Truckee River Upriver from the Tahoe City Dam. Source: Siig, 4/9/15.

Figure 13: The Truckee River Upriver from the Tahoe City Dam. Source: Siig, 4/9/15.

Further, as is the case with many western rivers, the water in the Truckee is already over-allocated. It is a principal water source for Reno, Nevada, for agricultural interests along its banks, and for Pyramid Lake. All of these communities would be devastated if the water were diverted. In the current drought, the level of Lake Tahoe has dropped below the natural rim of the lake, and flows into the Truckee River have ceased completely. (Figure 13) For these reasons, it seems unlikely that the Truckee River can become a source of significant new water for California.

The Colorado River is the only river to California’s south. As discussed in Part 2 of this series, it has already been tapped, and its reservoirs are in danger of going dry. No substantive rivers flow into the Pacific Ocean on California’s southwestern coast. The rivers along California’s northwestern coast have been discussed above.

Thus, no additional water seems available from untapped rivers and watersheds along or adjacent to California’s borders.

Figure 14: Barge in the Columbia River. Source: Van Horn.

Figure 14: Barge in the Columbia River. Source: Van Horn.

What about rivers outside of California, such as the Snake River and Columbia River? The Snake River is a tributary of the Columbia, running from near Yellowstone Park in Wyoming, through Idaho, to join the Columbia near Kennewick, Washington. It has a large enough discharge to be of interest, and it passes close enough to California to be of interest. The Columbia River would be a better alternative, however, so I will focus on it. It arises in British Columbia and flows through British Columbia and Washington, where it is joined by the Snake River, before running along the Oregon-Washington border to the Pacific Ocean. It is the third largest river, by volume, in North America. Its average annual discharge is about 192 million acre-feet per year. (Kammerer, 1990) At its closest, it is about 400 miles from the northern terminus of the California State Water Project.

Figure 15: Possible Columbia River Diversion Route. Source: My tracing on Google Earth.

Figure 15: Possible Columbia River Diversion Route. Source: My tracing on Google Earth.

One doesn’t have to be an engineer to imagine how this project would have to work. The Cascade Mountans run north-south along the western side of Oregon from the Columbia all the way to California. The best route for an aqueduct would run along the eastern slope of the Cascades, near the Deschutes River. The water would have to be lifted, then flow by gravity over a very long, gentle descent, as the aqueduct zigzagged along the irregular contours of the land. At Bend, Oregon, the aqueduct would have to turn southeast to find its way through scattered low mountains and high desert basins. There would have to be several lifts along the course of the aqueduct, as even the lowest route climbs almost 5,000 feet before reaching Lake Shasta. The route would be considerably longer than 400 miles because of all the zigzagging. To justify the project, its capacity would have to be a significant portion of California’s projected water deficit, perhaps the entire amount (25.1 million acre-feet per year).

In comparison, consider the California Aqueduct, the largest in California by capacity. It takes water from the San Francisco Bay Delta and transports it 444 miles to the Los Angeles Metropolitan Area. Along the way, it must lift the water a total of 1,926 feet. Its capacity is limited by the canal’s capacity, which is 9.5 million acre-feet per year, and by the capacity of the pumps that lift the water over the mountains, which is about 1.4 million acre-feet per year. The energy used to lift water over these heights is huge: one source estimates that the California State Water Project (the whole system, not just the aqueduct) is the largest electricity consumer in the state, consuming 5 billion kWh of electricity per year, or 2-3% of the state’s entire total. (Cohen, Nelson, & Wolff, 2004). Another source estimates that it requires 3,000 kWh per acre-foot to convey California State Water Project water to the Los Angeles Metropolitan Region. This does not include treatment, distribution, or other processing, it only includes conveying the water. The electricity is consumed by the pumps required to lift the water. (Wilkinson, 2007)

Thus, before even mentioning political and environmental concerns, an aqueduct to divert Columbia River water to California would have to be longer than the California Aqueduct. It would have to lift the water at least 2.5 times as high. And its pumping capacity would have to be almost 18 times larger. Upon arriving at Lake Shasta, the water would then enter the existing water distribution systems (primarily the Central Valley Project and California State Water Project). Their capacity would not be sufficient to handle the increased volume; the entire system would have to be re-engineered and upgraded. Construction of the Central Valley Project began in the late 1930s and construction on the California State Water Project was completed in 1997 – a span of about 60 years (not including planning). Megaprojects of this kind are more complicated and obstructed today than in the past, and upgrades to the current system would have to be accomplished without interrupting the delivery of water. Thus, there is reason to think that constructing a system to distribute water from the Columbia River throughout California would be a huge infrastructure project spanning many decades, perhaps as many as the original construction took.

Such a project would be very costly. The Central Valley Project cost $3.6 billion when it was built (starting in the 1930s), which would represent something like $61 billion in today’s dollars. (Environmental Working Group, 2004) A plan to build infrastructure to transport California State Water Project water around the San Francisco Bay Delta was estimated to cost $25 billion. (Boxall, 2013) Those tunnels represent only a small portion of the whole system. Thus, re-engineering the entire system would likely cost $100 billion or more, and that doesn’t even include building the new aqueduct from the Columbia River to Lake Shasta.

At the same time, additional generating capacity would have to be constructed to power the pumps, and also the transmission lines that would be needed to distribute the power. Currently, even though the California State Water Project is the state’s largest consumer of electricity, power requirements are offset because many of its reservoirs are at altitude, and generate hydroelectric power as they discharge their water. But that would not be the case with the Columbia River, which is near sea level. Given that it takes 3,000 kWh of electricity to move an acre-foot of water over the current system to Los Angeles, and given that the new system would be lifting 25.1 million acre-feet 2.5 times as high, the required electrical power would be at least 188 million MWh. This would require the construction of new generating capacity. Presumably it would have to be renewable power, as nuclear, coal, and natural gas would be objectionable for reasons I will discuss more fully in Part 5 of this series.

Finally, the same legal, political, and environmental issues encountered by the Klamath Diversion proposal would apply to the Columbia River idea. While the coastal regions of both Oregon and Washington receive copious precipitation, their inland regions are semi-arid. Both states are experiencing droughts, and their governors have declared drought emergencies. Oregon and Washington do not necessarily look with sympathy on their profligate neighbor’s water woes.

Megaproposals to divert Columbia River water are not new, actually, but, as one article says, “spokesmen for Washington’s and Oregon’s governors…laughed at the idea.” When the Bureau of Reclamation considered one such proposal in the 1960s, it was so objectionable that Congress passed a law stripping the Bureau of its authority to conduct even preliminary feasibility studies of new water diversion projects without Congress’s approval (not just Columbia River diversions, all diversions). The law effectively gives Washington and Oregon veto authority over any proposal to divert water from the Columbia River. (Fox, 2015)

Thus, it seems unlikely that California can find new groundwater or surface water resources to make an appreciable dent in its projected water deficit. This should not be surprising. California has studied and managed its water resources for many decades. They have already located and exploited every resource they could.

Only one alternative for new water remains: desalination. The next post will look at whether the state can procure significant new water from desalination.


Boxall, Bettina. 5/29/2013. “California Plan to Overhaul Water System Hub to Cost $25 billion.”
Los Angeles Times. http://articles.latimes.com/2013/may/29/local/la-me-delta-cost-20130530.

Cohen, Ronnie, Barry Nelson, and Gary Wolff. 2004. Energy Down the Drain: The Hidden Costs of California’s Water Supply. New York: National Resources Defense Council. Retrieved online 5/28/15 at https://www.nrdc.org/water/conservation/edrain/edrain.pdf.

Committee on Advancing Desalination Technology. 2010. Desalination: A National Perspective. National Academies Press. https://www.nap.edu/download.php?record_id=12184.

Environmental Working Group. 12/15/2004. California Water Subsidies: About the Central Valley Project. Webpage accessed 6/15/2015 at http://www.ewg.org/research/california-water-subsidies/about-central-valley-project.

Fox, Justin. 4/27/15. “William Shatner’s California Pipe Dream.” Bloomberg View. Retrieved online 5/28/15 at http://www.bloombergview.com/articles/2015-04-27/william-shatner-s-california-pipe-dream.

Hanak, Ellen, and Jay Lund, Ariel Dinar, Brian Gray, Richard Howitt, Jeffrey Mount, Peter Moyle, and Barton Thompson. Managing Californias Water: From Conflict to Reconciliation. San Francisco, CA: Public Policy Institute of California. Accessed online 54/28/15 at http://www.ppic.org/main/publication.asp?i=944.

Kammerer, J.C. 1990. Largest Rivers in the United States. USGS. http://pubs.usgs.gov/of/1987/ofr87-242.

Metropolitan Water District of Southern California. 2007. Groundwater Assessment Study, Chapter 4: Groundwater Basin Reports. Retrieved online 5/28/15 at http://www.mwdh2o.com/mwdh2o/pages/yourwater/supply/groundwater/gwas.html#4.

Santa Monica Public Works. 2015. Santa Monica Water Treatment Plant. Web page accessed 5/25/15 at http://www.smgov.net/santamonicawatertreatmentplant.aspx.

Slig, Melissa. 4/9/15. “News Briefs March 13-April 9, 2015.” Moonshine Ink. http://www.moonshineink.com/news/news-briefs-march-13-april-9-2015.

USGS (a). 2015. USGS Surface-Water Annual Statistics for California, USGS 10338000 Truckee R NR Truckee CA. Website accessed 5/25/15 at http://nwis.waterdata.usgs.gov/ca/nwis/annual/?search_site_no=10338000&agency_cd=USGS&referred_module=sw&format=sites_selection_links.

USGS (b). 2015. USGS Surface-Water Annual Statistics for California, USGS 11530500 Klamath R NR Klamath CA> Website accessed 5/25/15 at http://waterdata.usgs.gov/ca/nwis/annual/?search_site_no=11530500&agency_cd=USGS&referred_module=sw&format=sites_selection_links.

Van Horn, David. Barge in the Columbia River Gorge” (photograph). Flickr via Wikimedia Commons. [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)].

Wikipedia. 2015a. California State Water Project. Web page accessed 5/28/15 at http://en.wikipedia.org/wiki/California_State_Water_Project.

Wikipedia. 2015b. Klamath Diversion. Web page accessed 5/25/15 at http://en.wikipedia.org/wiki/Klamath_Diversion.

Wilkinson, Robert. 2007. Analysis of the Energy Intensity of Water Supplies for West Basin Municipal Water District. Report for the West Basin Municipal Water District. Los Angeles, CA: West Basin Municipal Water District. Retrieved online at http://www.westbasin.org/files/general-pdfs/Energy–UCSB-energy-study.pdf.

1 Comment

  1. […] here). The state will be unable to secure large new sources of surface water or ground water (see here), and will have to construct large, expensive desalination plants (see here). There will be […]

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