OWENS LAKE, Calif. » For 24 years, traveling across the stark and dusty moonscape of what once was a glimmering 110-square-mile lake framed by snow-covered mountains, Ted Schade was a general in the Owens Valley water wars with Los Angeles. This was where Los Angeles began taking water for its own use nearly a century ago, leaving behind a dry lake bed that choked the valley with dust, turning it into one of the most polluted parts of the nation.

The result was a bitter feud between two night-and-day regions of California, seeped in years of lawsuits, conspiracy theories, toxic distrust and noir lore — the stealing of the Owens Valley water was the inspiration for the movie "Chinatown." But while the water theft remains a point of contention, the battle long ago turned into one about the clouds of dust that were the legacy of the lost lake, 200 miles north of downtown Los Angeles.

In what may be the most startling development yet, the end of one of the great water battles in the West appears at hand: Instead of flooding the lake bed with nearly 25 billion gallons of Los Angeles water every year to hold the dust in place — the expensive and drought-defying stopgap solution that had been in place — engineers have begun to methodically till about 50 square miles of the lake bed.

That will create three-foot-high furrows that, sprinkled with far less water, together should scrub the atmosphere of the thick haze that often makes it impossible to see from one side of the valley to the other, with widespread complaints of asthma.

"All we wanted is air-pollution control," Schade said. "We just wanted to make it so it’s not so dusty."

Schade, 57, his pursuit of Los Angeles finally over, celebrated the moment by announcing he was retiring as the chief enforcement officer for the Great Basin Unified Air Pollution Control District. In that role, he installed video cameras and air pollution maintenance stations across the lake bed, haranguing the city to step in whenever air-pollution standards were violated.

No less striking, Los Angeles, after years of filing lawsuits against the basin asserting that the damage was not the city’s fault, is showing remorse.

"The city has accepted its responsibility," Eric M. Garcetti, the mayor of Los Angeles, said in a ceremony marking the agreement last month. "We took the water."

From one perspective, the agreement between the Great Basin district and the Los Angeles Department of Water and Power was a technical one, reflecting advancements in the science of controlling dust.

Yet more than that, the agreement — and the public contrition expressed by a new mayor, who arrived in 2013 — was a critical turn in a long-running tale that has at times riveted this state. It is a clash of cultures and regions, between a teeming metropolis and a sparsely populated expanse of mountains, valleys and lake beds, where temperatures range in a single year from 10 degrees to 120 degrees or more. About 31,000 people live across the three counties that make up the water basin — or about one person per square mile.

"We are very different people," said Ron Hames, a member of the Alpine County Board of Supervisors and chairman of the Great Basin board. "In my county, we don’t have a bank. We don’t have a Starbucks. We don’t have a single stop light. There are 1,172 of us — depending on the day."

William W. Funderburk, a Los Angeles lawyer who is vice chairman of the Department of Water and Power, said he was struck upon arriving by the tense atmosphere between the two sides. He and Mel Levine, a former member of Congress who is president of the board, were the lead delegates to the negotiations.

"There was no trust," Funderburk said. "It’s not an understatement to say that resolving Owens was similar to resolving the Israeli-Palestinian conflict. Bad blood had just been passed on through the generations."

The war began in the early 1900s, when agents working for Los Angeles, posing as farmers or ranchers, bought up much of the valley in search of water to accommodate the needs of a metropolis that was rapidly growing — and wanted to grow more. The city began diverting water from the Owens River into aquifers leading to Los Angeles in 1913. Within 10 years Owens Lake, which was fed by the river, went dry.

This was before the days of the Clean Air Act, and the region had no legal recourse against Los Angeles. But a combination of that law and state legislation passed in the early 1980s led to Los Angeles signing an agreement with the basin in 1997 agreeing to clean up the air pollution. It turned out to be just the beginning of years of bickering, as the city disputed how much the lake bed was causing the problem.

Schade, using dust-measuring devices, kept pushing Los Angeles to expand its efforts, and the city responded with lawsuits — including one challenging Schade’s authority as a regulator.

"They called in the attorneys," Schade said. "They told their staff not to talk to us. Their strategy had been to bury Great Basin in lawsuits."

A confluence of factors — starting with weariness brought on by years of fighting — was largely responsible for producing what once seemed impossible. The 25 billion gallons of water Los Angeles has been pouring every year on the lake bed, its main strategy for controlling the dust, was nearly as much as the entire city of San Francisco consumes in a year — a waste that became increasingly egregious as the state’s drought persisted. And Los Angeles was losing nearly every one of the legal challenges.

Garcetti was frustrated by the drain on the city’s finances and water supply caused by a fight that seemed frozen in time. Upon taking office, he instructed his new appointees to approach the dispute with negotiation.

"I think we were highly deferential in terms of understanding their concern, and appropriately so," Levine said.

Mike Feuer, the Los Angeles city attorney, said that history "is replete with stories about how deep the conflicts have been and how little trust existed."

"That paradigm has shifted dramatically," he added.

Still, one of the big concerns for Los Angeles officials was that this was a battle that seemed to have no end. A key concession that the city obtained was a ceiling on how much of the lake bed it was responsible for controlling, a subject of a continuing tug-of-war. Under the agreement, that area is up to 53 square miles.

Previously, "there was never a cap on square miles," said Richard F. Harasick, director of water operations for the city’s Department of Water and Power, speaking over the whirl of helicopter blades while offering an aerial tour of the battleground. "When is enough enough? That was the source of our angst. OK, we are responsible. When does that responsibility end? When are we done?"

For all the historical resentment of Los Angeles, there are some people here who suggest that, with the passage of time, there may have been some beneficial if unintended consequences.

"While people who live here might have resentment of what happened 100 years ago, we also have 33,000 square miles of open land that never got developed," said Matt Kingsley, an Inyo County supervisor. "It’s open and accessible. If it was all privately owned, this would be a lot different."

Schade said he was confident that the battle was finally over; if the fight were still going on, he said, he would still be heading out to the lake bed most days to check his monitors.

"I am retiring because I feel like I can," he said.

© 2015 The New York Times Company