Replumbing Los Angeles – Painfully Slowly
The City has captured 5.5 billion gallons of stormwater since October 1st — and that is literally just a drop in the bucket.
Tujunga Spreading Grounds: More Like This, Please
This caught my attention last week:
The Los Angeles Department of Water and Power says it has captured nearly 5.5 billion gallons of water since Oct. 1 following the recent storms.
Mayor Karen Bass’ office announced the estimate on Tuesday, saying it’s enough to serve almost 68,000 homes for an entire year.
According to the National Weather Service, downtown Los Angeles received more than five and a half inches of rain in November, making it the 5th wettest November on record – that’s dating back to 1877.
My first thought was that was big news: 5.5 billion gallons. But 68,000 homes isn’t as big as it sounds: ot basically totals a little less than 2% of Angelenos. Later in the article, DWP CEO Janisse Quiñones promises an annual average of 48,9 billion gallons, or 150,000 acre feet: but that actually represents only about 17% of the City.
Why can’t Los Angeles do better? Using advanced journalistic techniques unknown to most reporters, I picked up the phone and spoke with Art Castro, the head of the Department’s stormwater replenishment program.
“We’re losing up to 600,000 acre-feet a year to stormwater runoff,” Castro told me. That’s about four times what the Department is hoping to get in a decade. So why in the world are we only shooting for 150,000?
The problem is that of course a whole lot of rain hits private property. It would be great for Los Angeles to build new rainwater capture areas like the Tujunga Spreading Grounds (pictured), but anyone who has looked at property values knows that that isn’t the cards financially.
Conceivably, one could try to get it out of storm drains, but that would require an even more expensive massive repiping.
“I went to engineering school in the mid-90’s,” Castro said, “and they told us that we wanted to divert water, not capture it. Get the water away from buildings.” And that was the paradigm for most of the 20th century.
“But we have seen a paradigm shift about 10 years ago,” he continued. “We get our water from the Los Angeles Aqueduct and secondarily from the Colorado River. What if there is a huge earthquake? Those sources could be cut off. We need to expand our portfolio now.”
That will be amazingly expensive. The Department tries to get more stormwater capture from parks and schools as well: the idea is to put the infrastructure in both places. When it comes to schools, the Department can pay for great permeability, which also makes school playgrounds healthier and reduces heat island effects. And of course DWP also tries to incentivize things like rain barrels and cisterns, “but that is literally a drop in the bucket.”
Basically, for more than a century, Los Angeles — and most US cities — made themselves as unsustainable as possible. We woke up about two decades ago. That means turning an aircraft carrier around. And that is too slow. Sterner measures will be necessary. I don’t envy the politicians who are going to have to break it to the voters. They will soon be ex-politicians.
