Everyone in California is excited. All the signs point to a strong El Nino winter. El Nino’s usually (not always) mean more wintertime rain and snow in California. We need water. Supplies are running very low.
First, a few truths. What falls in Los Angeles, Palm Springs or Irvine means little! Some of it might enter the system, but we are primarily set up to harvest snow. None of those places get snow.
Our most efficient collection comes from spring runoff, meaning most of SoCal’s drinking water starts someplace else. The Coachella Valley mainly taps the Colorado River. Our drinking water’s watershed is hundreds of miles away in states that don’t even border California.
For Los Angeles and environs, water is transported via aqueduct from the Owens Valley at the base of the Sierras, also hundreds of miles away.
I’m not sure there’s any place in Southern California that’s naturally suitable for even a fraction of its current population density. The only answer is water from afar. It’s our pact with the devil. Even the most environmentally friendly of us uses more than SoCal can deliver.
As bad as this drought is (very bad), it’s absolutely wrong to look at how many inches below normal we are as a meaningful number. Water systems aren’t set up to need normal conditions. Water supplies must be over-engineered to provide cushion for bad years.
Normal precipitation supplies more water than we actually need. We don’t have to make up the entire deficit inch-for-inch.
I can’t find any specifics on how much precipitation is needed for positive inflow, but my suspicion is the bar is lower than people think.
Here’s my semi-educated guess. An average year’s rain would likely put us where we were two or more years ago, not where we stood last August.
What’s taken us seven years of mainly bad precipitation won’t need anywhere that long to recover.
So, I welcome El Nino with open arms and hope he doesn’t bring the usual ‘extras’ — flooding and landslides. Everything good in California has a price.