At the end of Wood Avenue in South Gate, unseen behind its levee, the ephemeral giant strained in its cage.
The raw power drew Rita Adams for the first time in her 40 years of living in the neighborhood. She and her son walked under bare winter elms, past tidy postwar homes with American flags flapping in the rain, up the sandy embankment of an old Union Pacific track, to the top of the concrete channel.
She lit a cigarette and shook her head. "Wow."
The Los Angeles River had awakened.
The sheer breadth and speed of the water was disorienting, enough to make you lose your balance glancing back to solid land.
The river at its peak can move 146,000 cubic feet of water every second. At its normal rate, the Colorado River, sculptor of the Grand Canyon, doesn't do a quarter of that.
For the record
Jan. 7, 9:41 a.m.: An earlier version of this post implied a comparison between peak water flows of the Los Angeles and Colorado rivers. The comparison was between the peak flow of the L.A. River and the normal flow of the Colorado. It also misidentified Los Angeles' Spring Street bridge as the Second Street Bridge.
Adams stared at the choppy sheet of brown water as it exploded against the piers of the railroad crossing. Others came to watch, too, much as people gather at the shore to watch a violent sea.
"It's fabulous," Adams said. She studied the trash and logs and arundo cane hurtling south to Long Beach.
She said some of her neighbors come here when it's dry to walk their dogs, but she'd never bothered to check it out.
Like most residents of the Los Angeles Basin and San Fernando Valley, she rarely gives the river in her midst much thought. Cities put their backs to it. For most of the year it withers to an algal trickle of treated sewage in the low-flow slot at the center of the channel.
Scrap yards, steel plants, rail yards, freeway embankments and homeless camps line much of it, although a decades-long effort has slowly adorned it with more parks and natural space, and there are grand plans for more.
But El Niño storms like this week's bring back a glimpse of the river's historic moodiness and might: the volatile beauty that once murmured through the arroyo willows, then reared up and wiped out the original pueblo that took its name, that switched course by 30 miles one year, that killed 45 people in flooding in 1938, that the city, county and federal governments thereafter spent two decades and hundreds of millions of dollars to tame.
When the Spanish government decided in 1777 to construct its first agricultural settlements in California to feed the missions and presidios, they picked a site on high ground west of the river they called El Río de Nuestra Señora La Reina de Los Ángeles de Porciúncula.
The namesake settlement of Los Angeles became the second city in California after San Jose, with a water ditch — the zanja madre — diverting flow to the city.
The river, its tributaries and artesian wells made Los Angeles County one of the biggest cattle and food producing centers in the nation. Fishermen caught steelhead trout in the pools, and waterwheels ran flour mills in the currents.
But as Yankee newcomers poured in during the 19th century and settled on lower-lying areas, they suffered catastrophic floods.
After epochal rains in 1862 turned much of the basin into a lake, residents began clamoring to raise the banks of the river and build upstream dams.
What made the river so tempestuous was topography. Pacific storms stall against the San Gabriels, some of the steepest mountains in the world, with sparse vegetation to slow down the rainwater as it plummets down granite canyons.
Water from 834 square miles of rugged terrain, some higher than 7,000 feet, drains into the L.A. River. Excluding the mountain washes that feed it, the main river drops 800 feet from its source in Canoga Park to its mouth in Long Beach, 51 miles away. The Mississippi drops that much over 2,300 miles.
In March 1938, storms hammered the region. Los Angeles got over 6 inches of rain in one day, and 32 inches soaked the San Gabriels over five days. Bridges, roads and rail lines washed out, houses collapsed.
Eighty-seven people died in flooding throughout the county and 108,000 acres were deluged.
Major projects to control the river began immediately with federal funding. Led by the U.S. Army Corps of Engineers, workers dug deeper and wider channels, carved out flood control basins, and built reservoirs.
By 1959, the river had become the "water freeway" that it is today.
"What do you guys say, 25 miles an hour?" Ernesto Ortiz, 26, asked as others gathered at the railroad bridge in South Gate.
No one there could outrun it. Ortiz tried and didn't come close.
The truck traffic on the 710 freeway crossing just downstream moved about the same speed, but looked less ferocious by comparison. You'd have a better chance crossing that rainy freeway alive than trying to swim across the torrent where people normally walk their dogs and ride BMX bikes.
"Oh, you see that log just crash against the pillar," Ortiz exclaimed.
Upstream in Lincoln Heights, Gergorio Lopez, 63, got off work and told his friend Olegario Plazola, "Let's go see the river."
Originally from the rainy Mexican state of Guerrero, Lopez finds peace in the moving water. From the Buena Vista Street bridge, he looked south to the Spring Street bridge, where the pier cut through the water like the bow of a battleship.
Lopez chewed on a toothpick and gazed down, mesmerized.
As powerful as it looked, the river was nowhere near its max.
Only one spot along its course had exceeded a third of its capacity as of Wednesday afternoon, according to the county Department of Public Works. At 3 p.m. in South Gate, the flow was 18,434 cubic feet per second.
But the river could get meaner as more storms soak the region.
Due to the long drought, much of the mountain runoff is still being captured in reservoirs and storm basins.
Big Tujunga reservoir was 32% full Wednesday, said Eric Batman, a senior civil engineer at county public works. Below it, the Tujunga Wash, one of the river's major sources of water, was dry. Likewise, the Devil's Gate dam was storing water instead of releasing it into the Arroyo Seco.
"This could definitely change," Batman said. "If we had weeks more of this stuff, we could see more of our dams making releases."
Still, El Niño has come before, and the giant hasn't got out of its cage yet.
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