How LA brought water to its booming population

How Los Angeles got its palm trees

Los Angeles is known for its warm weather and palm trees, but the latter haven't always been part of the landscape. As Hollywood's movie industry grew, so did the number of palm trees. As this article points out, most of the city's palm trees were planted in the 1930s through an unemployment relief program.

LA used to have one of the best mass transit systems in the country

A century ago, Los Angeles had one of the greatest urban transit networks in America. Today, driving in LA traffic can still be faster than taking the train. The city's rail design, which funnels traffic through a single point, fails to support a city with such a spread-out population.

Los Angeles once suffered some of the worst smog on Earth

From the 1940s through the 1960s, Los Angeles was blanketed by dense, eye-burning smog so severe that drivers sometimes couldn't see traffic lights. The issue led to the nation's first local air pollution controls and inspired the passage of the 1970 Clean Air Act.

In 1974, Los Angeles’s Community Analysis Bureau built a smart city

Los Angeles utilized aerial imaging and cluster analysis to gather and interpret civic data, leveraging surveillance technologies developed by the Department of Defense during the height of the Cold War. Instead of being used for military purposes, data insights helped direct social services to high-poverty neighborhoods.

Side-by-side shots of once-dry California lakes now filled

In late 2022, much of California was in drought; by early 2023, after a series of downpours from atmospheric rivers, much of the state's reservoirs had been re-filled. See the dramatic difference in this series of photos.

Eleven aqueducts funneled water to Rome's 1 million inhabitants

The Roman Empire's capital city was home to about one million people at its peak and managed to provide running water to many of its homes, fountains, and public baths. This was made possible by the 11 aesthetically grand aqueducts that poured into ancient Rome from the countryside.

The Erie Canal fueled a surge in westward settlement

By providing cheap, reliable transport to the interior, the canal made western lands more accessible. Farmers, traders, and immigrants moved into the Great Lakes region, accelerating population growth.

Hollywood's efficient response to the Spanish flu made it a filmmaking destination

In 1918, the Great Influenza epidemic killed more than 675,000 Americans. Los Angeles was one of the first cities to shut down movie theaters, most of which were independently owned and couldn’t afford the revenue loss. The results were twofold: the quick response meant that Hollywood could bounce back faster than other film hubs, and it also contributed to the rise of vertical integration as studios stepped in to purchase the flailing theaters.

Bottled water started as a 19th-century wellness trend

Selling drinking water in America began at resorts in New York and West Virginia, where tourists were encouraged to take the regenerative mineral water back to their homes.

Why water towers are built that way

Local governments are responsible for more than 148,000 public water systems across the US

From large municipal utilities to small rural systems, local governments are tasked with providing clean water to almost every American community. The US operates over 148,000 public water systems.

The Alhambra’s medieval water system powered a palace-city

Built over centuries by Islamic rulers in medieval Spain, the Alhambra used canals and pressurized tanks to move water throughout the complex. Its sophisticated system supplied fountains, baths, and gardens, showcasing advanced medieval engineering.

Understanding how the commodification of water has contributed to global water scarcity

In 2010, the UN General Assembly recognized access to water and sanitation as a basic human right, noting that an estimated 884 million people worldwide lack access to safe drinking water. The treatment of water as a commodity and reserves as property has contributed to unequal access and competition over its use, which is expected to intensify due to climate change.

Cities bore the brunt of the migrant surge in the 2020s

During the 2022-24 migration surge, cities such as New York, Chicago, and Denver faced shelter overcrowding, strained public services, and housing shortages—while the upfront costs fell almost entirely to states and cities.

Biologists believe over 5,000 coyotes inhabit LA as of 2025

Panic and fear of coyotes spread in the 1980s after the first recorded instance of a human killed by the animal in American history, but LA and Chicago residents today are learning to live alongside the animal. Research shows that coyotes can even benefit urban ecosystems by helping to control populations of geese and deer, and by improving songbird survival through preying on cats.

The evolution of Mexico City, from the Aztecs to today

The sprawling modern city situated in the Valley of Mexico began a millennium ago as an island in the middle of Lake Texcoco, connected to land through a series of causeways. Learn how the Aztecs built Tenochtitlan, how the Spaniards conquered it, why the lake disappeared, and more with this visually rich history and geography of a city of 9 million people.

Atmospheric rivers are the largest freshwater transport mechanism on Earth

Serving as highways that carry the water vapor equivalent of up to 15 times the average flow of water at the mouth of the Mississippi River, atmospheric rivers are approximately 400 to 600 kilometers (250 to 375 miles) wide and provide 30-50% of the annual precipitation of the US West Coast.

What happens when the population grows faster than the food supply?

Human history is shaped by our ability to feed ourselves. See how population growth is tied to farmland, and how food production’s profound environmental effect shows us the need for change.

Paris and Boston were redesigned partly to combat cholera's spread

Georges-Eugène "Baron" Haussmann, who oversaw Paris's redesign in the 1800s, replaced many of the city's narrow streets with wide boulevards. This was done at least in part to bring more air and light into the city to help control cholera. Architect Arthur Gilman redeveloped Boston's Back Bay to similarly combat cholera, among other reasons.

Before Silicon Valley became the largest tech hub in the world, it was an agricultural area known for its flowers and fruit

It was called the “Valley of Heart’s Delight.” This video by Vox explains how the area went from growing prunes to producing computer chips. It also explains how Stanford University had a big impact on the area’s development.

What was the London Beer Flood of 1814?

On this day 209 years ago, a 15-foot-high wave of beer roared through the streets of an impoverished London neighborhood, killing eight people. Read this beer historian's account of the tragedy to learn more. The beer had burst from the nearby...

Ranchos were large land grants in California to Spanish, Mexican leading families

They were typically given to leading families or retired soldiers as means of settling the land with loyal people. The hundreds of ranchos have since shaped land-use policy in the area, determining plots of major cities and ranches today.

Disneyland opened in 1955

Walt Disney teased the amusement park a year in advance through his ABC show, "Walt Disney's Disneyland." This episode was from the park's opening day, an event that necessitated a news-like live broadcast and walked viewers through the park's attractions and amenities. One in three Americans watched the broadcast, despite its numerous technical difficulties.

The adoption of modern appliances led to the soap opera's rise

Soaps grew more popular as they transitioned to television in the 1950s. At the same time, the adoption of modern appliances like the automatic dishwasher and the clothes dryer offered housewives more free time, which soaps could now occupy. By 1970, CBS, NBC, and ABC were airing 18 daytime soaps.

South Korea's decades long effort to build a new capital

South Korea has spent decades trying to ease overcrowding in Seoul by developing Sejong City as a new administrative hub. Named after the king who created Hangul, Sejong was designed to decentralize government functions—but slow population growth and limited transit have complicated the plan.

Stanford built a Google Maps for the Roman Empire, revealing how much it cost to travel in the ancient world

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

The use of fungi to detoxify land and water—a process known as mycoremediation—has been used to clean up natural resources affected by the 2025 California wildfires.

In 1915, workers recovered a submarine-like vessel from the Chicago River, prompting fears of German espionage

Electrical grids worldwide must double their power delivery capacity by 2050 to meet surging demand from AI and electric vehicles.

See a 3D reconstruction of Tenochtitlan, the Aztec capital that was home to an estimated population of 200,000 to 400,000.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

Before writing 'Walden,' transcendentalist Henry David Thoreau nearly burned down his hometown with a campfire that grew out of control.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

Walt Disney's early film 'Alice's Wonderland' was a groundbreaking innovation in the silent film era

At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

When a Paris department store hesitated to sell Estée Lauder's perfume, she 'accidentally' broke a bottle, causing the smell to spread throughout the store and shoppers to start asking to buy the scent.

Massive 3D printers have been used to build homes by stacking layers of 'concrete toothpaste,' a fire-resistant material that effectively insulates against outside noise.

The boiling temperature of water decreases with increasing elevation because the molecules need less energy to overcome the lower atmospheric pressure associated with thinner air.

Hear about the 250-year history of the United States Postal Service, complete with some of its strangest deliveries, important innovations, and the figures that made it an American institution.

The Great Salt Lake's distinct dual coloration results from high-salinity organisms that only live in the northern portion and produce a purple protein.

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

Jimmy Carter signed a 1978 bill that legalized home brewing, a move credited with kick-starting the craft beer industry.

20,000 letters to the advice columnist 'Dear Abby' provide insight into prevailing sex, religion, and LGBTQ fears, anxieties, and concerns from the 1950s onward.

Gerrymandering works through two techniques: cracking opposing voters across districts to dilute their power, and packing them into a few to waste their votes in lopsided majorities.

For centuries, Niagara Falls has been a magnet for daredevils seeking to conquer one of nature's most powerful wonders, with its 200-foot drop and water rushing at 32 feet per second with 280 tons of force.

The US first hosted the World Cup in 1994, a tournament that lives in soccer infamy for its poor planning and the murder of Colombian player Andres Escobar, who'd accidentally scored on his own net.

US consumers collectively owe more than $1T to credit card companies—almost as much as they owe in auto loans.

To reduce wrinkles in clothing, research recommends gentle wash cycles with more water and tumble drying with smaller loads and longer times.

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.