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The Colorado River’s First Dam Transformed The Desert Southwest

The Laguna Dam in an undated, historic photo.

Photo by Bret Jaspers/KJZZ

Above: The Laguna Dam in an undated, historic photo.

Jim Cuming is a retired farmer whose grandfather immigrated to the U.S. from Ireland. Edward Cuming got 160 acres in Arizona's Yuma Valley from the federal government.

Jim Cuming said the land was as undeveloped as a dry riverbed. In order to survive and develop the farm, his grandfather had to make a living.

“This Laguna Dam project opened up. So they moved up to the dam and he worked on the dam there as a carpenter,” he said.

That means Cuming’s grandfather helped build the dam that made it possible to irrigate his own farmland.

We all know Hoover Dam, and you might know about the Imperial or other dams that manage the Colorado River. But the very first dam on the Colorado was the Laguna Dam, completed in 1909. It diverted water to farm fields in the Yuma Valley and set the table for large-scale farming in southwest Arizona.

The Cuming farm and so many others have thrived due to the Laguna Dam and later Colorado River projects.

“It’s created a tremendous amount of wealth in the community and the state and the nation,” said Cuming, who’s also president of the Yuma County Water Users’ Association. “I mean, we send produce now all over the United States, Canada, even ship it overseas.”

The Reclamation Service — now known as the Bureau of Reclamation built the Laguna Dam at a cost of $2 million. In January 2018, workers at the Laguna Dam were repairing the original concrete from over a hundred years ago.

Doug Cox at the Imperial Irrigation District manages the dam.

“Because this is historical, we have to maintain it,” he said.

The Laguna has gates along the California side that are now sealed. Back when the dam was still used for large-scale irrigation, operators would release the water out of those gates. It would flow along a canal to an area north of Yuma. The water then had to cross back under the Colorado River through a siphon. Canals then carried it to the Yuma Valley and the City of Yuma.

Photo by Bret Jaspers/KJZZ

A farm field in Yuma, Arizona in an undated photo.

Despite its usefulness in irrigating crops, the Laguna Dam is small, and not built to store water. Crops could still be wrecked by floods.

“This is not a storage dam. It’s a diversion dam,” Cox said.

Colorado River flooding didn’t get fully under control until the Hoover Dam started storing water in 1935. These days, the Laguna Dam doesn’t do much more than divert overflow after a big rain.

The Yuma siphon is still in operation, although the water comes down from the All-American Canal. That canal takes diverted Colorado River water from the Imperial Dam to Imperial Valley in California.

Yes, there are more dazzling structures in place today. But the Laguna was the first step in harnessing the Colorado River to create both safety and prosperity.

It was also built at a time when the West was undergoing a dramatic change.

“I think the Laguna Dam is reflective of having the West become domesticated, more and more,” said Tina Clark, a historian for the city of Yuma, Arizona.

Construction wrapped up on the Laguna Dam the same year the Yuma Territorial Prison closed. Coincidentally, Clark owns a restored church in Yuma, also built in 1909.

“The domestication really came with the churches, and bringing your wife and becoming a farmer,” she said. "It was the Wild West pioneers — the miners, the guys that came alone — versus the guys that brought their wives.”

The farming life drew Jim Cuming’s grandparents to the Yuma Valley. Dams — starting with the Laguna — allowed his family farm to thrive there, at least, until the river got under control.

“It made it real tough. And that’s why the Bureau of Reclamation created these places and it’s been a godsend down here,” he said.

It’s hard to argue with him when you visit Yuma at harvest-time, passing acres and acres of winter vegetables. Fields as green as the surrounding hills are dry.

This story is part of a project covering the Colorado River, managed by KUNC in partnership with public media stations in the southwest. The project is supported through a Walton Family Foundation grant. KUNC is solely responsible for its editorial content.

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