Good morning, and welcome to the Essential California newsletter. It’s Monday, Jan. 16. I’m Ryan Fonseca, and I miss the sun.
California hasn’t seen much of it this year as a parade of storms continue to flow over much of the state, bringing record rainfall, severe flooding and at least 19 deaths.
It’s estimated that 24 trillion gallons of water have fallen on the state (not counting this weekend’s storms). But many places in California aren’t able to keep most of that free water. In Los Angeles County, for example, only about 20% of the runoff from recent storms will be captured, my colleague Hayley Smith reported.
It’s hard to determine how much stormwater is captured and reused. But according to the Pacific Institute, California’s urban areas are letting between 770,000 and 3.9 million acre-feet of water spill away every year (depending on how dry or wet the year is).
That’s a problem for our drought-laden state as officials look to modernize our infrastructure and shore up stormwater capture to save for more dry days ahead.
Californians each year use 20 trillion to 30 trillion gallons of water for agriculture, urban and environmental purposes , officials wrote in Water Supply Strategy, released in August.
With the state’s available water supply expected to shrink up to 10% by 2040, rainfall represents a vital resource that’s mostly just spilling into the Pacific.
That’s where the new strategy comes in. One goal: “create storage space for up to 4 million acre-feet of water, allowing us to capitalize on big storms when they do occur and store water for dry periods.”
One acre-foot of water, or the amount it takes to fill an acre of space one foot high, is about 326,000 gallons. So that 4 million acre-feet goal would mean about 1.3 trillion gallons.
There’s a whole lot of natural water storage space many urban areas have neglected: underground aquifers. For decades, engineers opted to build concrete drains, channels and other…