Ernest Johnson, my grandfather, was unable to eek out a living in the 1930s solely by raising crops on his small farm in rural Leonard, Minnesota. One of many places he out-sourced his physical labor was at the Hoover Dam construction site on the Arizona/Nevada border, about 35 miles southeast of Las Vegas. My mother does not remember exactly how long her father was away from home while working at the site, but it seemed a long time to a girl in her early teens. In any case, the employment probably extended for a period of six months up to a year, somewhere between 1931-1935.
Grampa was not a large man, perhaps standing about 5'5" or so, but like others of his generation and before, he could work extremely hard. I still have one of the shirts that he was fond of wearing: a sturdy button-down wool flannel in a red and gray plaid. When he outgrew it by a few spare pounds in his elder years, he gave it to my mother. She wore it outside while gardening for quite awhile after that and then passed it down to me. I am only 5'1" but I have never really been able to wear that shirt, in a man's small size. It rests, lovingly folded, among other treasured items in my cedar chest.
I remember sitting on Grampa's lap as a child, but being very young, I had no sense of how he compared to others back then. He was just "Grampa"--my only grandfather--with an interesting accent and a crinkly smile. He sometimes smelled of pipe tobacco or bacon, and I never knew him to go anywhere without a hat or cap. I always understood that underneath that shy smile and spare, straight talk there was an unshakeable fortitude... a fierceness even, that I'll liken to a pioneer spirit. I felt safe whenever he was near. Grampa loved a good laugh, but he had no tolerance for utter foolishness. I was more than okay with that since since I was a rather subdued child to begin with, but I really only wanted to please him, or any of my elders, for that matter.
I wish I knew something specific about the work my grandfather did on Hoover Dam, which was renamed Boulder Dam in May 1933. The family just always knew that Grampa spent a fair amount of time working on "that dam with the two names." To be certain, it was some variety of sweaty, back-breaking labor under the heat of the desert sun: there was no escaping it in one of the hottest and dryest regions of the United States.
Work on Boulder City began in December 1930. The original plan called for completion of the town before work on the dam began, but the construction schedule for the dam was accelerated, and the town was not ready when the first dam workers arrived at the site in early 1931. During the first summer of construction, workers were housed in temporary camps while work on the town progressed... 
It is likely that Ernest Johnson arrived in Boulder City by train and lived in a company dormitory. Reporting to work each day, he had to stop at security check point and present an employee card. All those entering the work site were expected to obey the posted regulations, which included not bringing "intoxicating liquors, narcotics, explosives, or firearms..." onto the site. Many employees rode in large groups on the large motor lorry ("Big Bertha.") 
The road from Boulder City to the canyon rim, about seven miles, was constructed for the Government by the General Construction Company. Designed to transport men and equipment to and from the dam site, these roads later formed a link in the main highway between Las Vegas and Kingman, Arizona. 
The U. S. Bureau of Reclamation posted signs along the trecherous canyon rim:
To accommodate the workers and their families at Boulder City, Six Companies constructed housing for both single and married employees, a fully stocked department store, a post-office, laundry, recreation hall, school, and hospital. Single employees at Boulder City were housed in eight 171-man dormitories, and one 53-man dormitory. The bunkhouses contained water coolers, toilets, and one shower for every 13 men. For $1.60 per day, workers received a private room with a bed, mattress, pillow, bedding, a chair, meals, and transportation to and from the construction site. In addition to the dormitories at Boulder City, Six Companies constructed six dormitories and a 400 man mess hall at Cape Horn, a bend in the river downstream from the dam site. 
The concrete arch-gravity Hoover/Boulder Dam was the world's largest electric-power generating station and largest concrete structure when it was completed in 1935. For images of the construction, visit the Bureau of Reclamation Hoover Dam website.
When Ernest Johnson ended his stretch of employment at the site, he remembered his daughters before heading back home to Minnesota with his earnings. At a local store, perhaps in Las Vegas, he purchased a purse and a pearl necklace for each of them. These were very special presents for the girls, particularly during the Depression era, although they never received their necklaces. Someone stole the pearls from among Ernest's belongings before he left the dormitory. Strangely enough, the purses were left behind--unlawful greed mixed with a twinge of guilt on the part of the thief? Or, perhaps the purses were simply not as portable as the jewelry. Grampa, being a practical man, had allowed a certain amount of money for presents, and when the necklaces were gone... well, they were gone. The thief was lucky to have gotten away undetected, because Grampa could be hot-tempered if the need arose, and he was not afraid to defend himself. Although my mother and aunt were disappointed over the loss of the necklaces, they did appreciate their father's thoughtfulness, and they treasured their purses all the more. My mother still has hers to this day: a hand-carved leather shoulder bag with a metal clasp.
While back on his farm in Leonard, Minnesota, Ernest Johnson used some of his WPA wages to buy new seed, after which he spent a few years successfully raising alfalfa, flax and clover to sell for feed. He found it increasingly difficult to farm due to a physical incapacity, however. Years before, a horse had stepped on his ankle, and arthritis had slowly set in.
Ernest Johnson with his dog, Pee Wee, near Leonard, Minnesota,
1941: a few years before he sold the farm and moved to
In preparation for his retirement years, Ernest Johnson sold his farm at age 56 and moved to Richmond, California along the Pacific coast. He went to work as a custodian for the Ford Motor Company in 1945, first living in a boarding house due to a housing shortage, and then renting a room atop a water tower. Other family members, his two daughters included, had already made the move out west from Minnesota, since California was the land of new opportunity to midwesterners after the heavy industrialization experienced during World War II.
As with many others during the Depression era, the WPA wages from the Hoover/Boulder Dam reconstruction project and others gave my grandfather the means to support himself until he was ready to make the transition from farming to a different way of life. It was not a hand-out, but a "hand up." Thus, those who were willing to work hard and carefully use whatever wages could be earned, were able to turn the "Dirty Thirties" to their advantage, in spite of difficult times, as did my grandfather.
[1, 3, 5] The Boulder Canyon Project: Hoover Dam, by Wm. Joe Simonds
[2, 4] The Boulder Canyon Project, AKA Hoover Dam