What’s the big deal?
By Milt Burgess
From global warming to rising sea levels to threats of rampant inflation, we are on the brink of so many disasters it’s hard to keep track, and now there’s a water crisis? Except for some local interruption of water service for repairs – we’re doing fine. What’s the big deal?
Twenty-two million people live in Southern California– in a desert. What’s a desert? One definition says it is an area where the annual rainfall is under ten inches. San Diego’s average precipitation is 10.77 inches per year, but lately it has been significantly below that. This is a desert because, naturally, even that rainfall runs into the sea with no natural local storage. The lower rainfall in itself would not be a cause for except that San Diego lies hundreds of miles from our water sources, the State Water Project and the Colorado River, and those sources are subject to natural disasters.
First the State Water Project: this relatively new source of water developed within the last sixty years originates in the Sacramento-Joaquin River Delta five hundred miles north of San Diego. Although there have been literally hundreds of studies about this source, the fact remains the delta levees sit directly over one of the most active earthquake faults in the world, the San Andreas.
“The southern San Andreas fault, Cascadia subduction zone, and the eastern San Francisco Bay area faults generally have elevated hazard relative to the time-independent maps. This is because it has been quite a long time since the last earthquake—about 150 years since the 1857 M 7.9 Fort Tejon earthquake, 300 years since the 1700 M 9 Cascadia earthquake, and 137 years since the 1868 M 6.8 on the southern Hayward fault. All of these faults are, most likely, in the latter half of their seismic cycles.” 
It is not just mild speculation about the probability of an earthquake striking this region, seismic experts predict it could happen within the next 30 years. When that happens, the aging delta levees will liquefy causing freshwater to mix with salt water. The result is the 10,000 cubic feet per second flow in the State Water Project will become saline and therefore useless for human consumption. Fix it? Not likely. It would take years to repair the damage, and in the meantime the socio-economic effects would be catastrophic.
Now the Colorado River: Seven states rely on this river for fresh water, the siltiest for its size in the world. It is regulated by the Colorado River Compact. Unfortunately when the river was divided up among those states the river flows used were from the wettest years in the river’s history. Never, since the compact was formed has the river produced close to what was originally calculated. Added to this is the plain fact that the Bureau of Reclamation has for the past several years been releasing more water from Lake Mead than it receives. Because Lake Mead has been dropping in level, the City of Las Vegas moved forward with a second pipe line (they depend entirely on the lake) that functions much like a bathtub drain, exiting the lake from its bottom so they can be sure to get the last drop.
Meanwhile, the San Diego area has not planned for the reduction in water flows to the region, except to negotiate a deal with the Imperial Irrigation District (IID) to transfer water from that area with its source the Colorado River. Currently the San Diego County Water Authority (SDCWA) is in a pitched legal battle with the Metropolitan Water District of Southern California (MWD) over the “wheeling rates” MWD is charging for using their pipelines to get the IID water to San Diego. A little known fact is that the agreement between the MWD and SDCWA contains a clause that says: in a water shortage, San Diego water can be reduced by as much as 50% if Los Angeles needs the water.
Is there a water crisis? Not yet, but some City planners are betting it never happens. The facts tell us otherwise. One bright spot is the Carlsbad Desalination Plant just under construction. However, that plant can supply only about eight percent of San Diego area needs. The answer to the not-yet crisis is indirect potable reuse (IPR) or recycling of water. This “term of art” means the sewage from San Diego would be treated to drinking water quality, piped to the San Vicente Reservoir, mixed with whatever water is available there and then treated again at the current water treatment plants before it is delivered to San Diego residents. How much will that cost? Estimates have been made, although as time goes on they may be too low, that IPR will cost about $2.2 billion dollars.
Is it worth it? That question can only be answered by calculating the cost of the loss of the water sources that San Diego currently enjoys. The socio-economic losses could be worse than the devastation caused by Hurricane Katrina or the more recent calamity that struck New York City.
That’s the big deal!
 (Working Group on California Earthquake Probabilities, USC-SCEC/CEA Technical Report #1 Milestone 1A, Southern California Earthquake Center, Los Angeles, 2006.)