In an average year the city of Los Angeles receives 13 billion gallons of water in the form of rain. (15 inches of annual rainfall x 503 square miles of city land is 13 billion gallons.) According to the LA Department of Public Works the city uses about 13 billion gallons of water each year. Some years there’s more or less rain and some years the city uses a bit extra or a little less, but the numbers are very close. Of course, the “city of LA” is only a small portion of the greater southern California metroplex, but the numbers are the same proportionally for the aggregate municipalities in the region from Torrence to Thousand Oaks to Anaheim to Pomona and everything in between. So why is there a perpetual water crisis?
Well… the rain hits the surface of Los Angeles and has no place to go. Most of the city – the office parks, shopping centers, tract homes, and roads – are waterproof. This is just as true in the leafy suburbs as the dense downtown core.
All the rain that falls in LA is gathered up as quickly as possible, funneled in to a massive complex of concrete channels, and flushed out to sea. Without this flood control infrastructure large portions of LA would be seriously water damaged each winter. That’s because whole swaths of the metroplex were built on natural flood plains. That was a bad idea, but it’s too late to fix it now. The better approach would have been to build clusters of towns on the high ground and use the flood plains for local agriculture. Instead every available inch of land was covered in Sheetrock and asphalt.
LA flushes away it’s rainwater and then has to import water from distant sources in northern California, Arizona, Colorado, and Nevada. Water flows through concrete aqueducts for hundreds of miles and is then pumped over mountains to get to where it’s needed. This is fantastically expensive, complex, and energy-intensive. That little blue ribbon of extremely vulnerable delicate infrastructure is the only thing keeping 19 million people in Southern California alive. Cut it off for a week and the city falls apart.
There is no real alternative at this point. So the future will bring higher costs, rationing, political and cultural angst, and the occasional devastating break in the system that will need to be patched. People need to think about how they’re going to adjust to this reality ahead of time. Hint: moving to Scottsdale or Vegas doesn’t solve your problem.