The report this week on the Missouri Valley is the largest color-picture supplement ever to appear in TIME: eight pages, including a two-page map, with a two-page story about the valley --breadbasket and problem child of the U.S.

In the course of his preparation for the story, TIME Writer Alvin Josephy received a fitting baptism into the problems of the Missouri Valley during a 2 1/2-week tour of the region last April. During his flight from St. Louis to Omaha on the first leg of his trip, his plane was ordered to land at Des Moines, with the explanation that the Omaha airport, threatened by the rising Missouri River, was shut down. Josephy and two other passengers hired a cab to take them 160 miles across Iowa to Omaha. Even the cab driver needed extra persuasion to cross the last bridge still open across the Missouri River from Council Bluffs to Omaha.

Josephy spent two days in Omaha. While watching sandbags being piled on the levees just one step ahead of the rising river, he was pressed into service in a chain of men passing the heavy bags from hand to hand. Working in the mud and rain to help ward off the greatest Missouri River flood on record, Josephy soon found out just how devastating an enemy the river could be.

The Missouri Valley story actually had its beginnings a year ego, when Josephy was in Washington to check with the Bureau of Reclamation and with Army engineers on newsworthy construction projects which should be reported in the News in Pictures section. He reported his findings to Executive Editor Dana Tasker, who was especially struck by the enormous amount of work going on in the ten-state Missouri Valley, and decided the time was right for a major color-picture story on this area.

Josephy went to work gathering material on the Missouri Valley preparatory to writing a shooting script for the photographers who would take the pictures. His first discovery was that there was no readily available source of information on the entire subject: all the land that is drained by the Missouri River and its tributaries, its agriculture and industries, the problems of the region, and what was being done about those problems.

Josephy spoke with officials in six federal agencies involved in flood control, land reclamation, conservation and power production in the valley, discovered that few of them had the complete picture of what the others were doing. Also involved were the governments of the ten states and various industrial, agricultural and private development agencies. Says Josephy: "When I asked, 'How many dams are being built in the valley?' nobody could tell me."

So Josephy set about learning what he could from all of them. He wrote letters to railroads, industries, chambers of commerce, local and state development boards, highway commissions, industrial development agencies, newspapers, and even to the Dude Ranchers Association (a sizable industry in some of the valley states).

He wrote his first script before he visited the valley, revised it when he returned from his tour. Three photographers were assigned to get pictures for the story. The views of the great plains and rivers, taken from the air by George Hunter, turned out so well that TIME decided to use only those.

Hunter, a meticulous worker, delayed starting the job for three days until he could get a fresh supply of the film he wanted.

He used aerial Ektachrome film, developed by the Army during the last war to take air views of camouflage installations in color. Then he packed his exposed film carefully in excelsior and shredded newspaper, sent it to Associate Editor John McCullough, who decided, after finishing the unpacking job: "Those rolls were wrapped like Egyptian mummies." For a look at the pictures finally selected, and for the story of what is going on in the far-flung reaches of the Missouri watershed, turn to the special section on the Missouri Valley in the center spread of this week's TIME.

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