Once a job is attained the undocumented worker needs nearby shelter. The low wages and lack of transportation and the desire to send as much money as possible home to family in Mexico necessitates sharing cramped quarters in unhealthy conditions.
In the case of many rural outdoor jobs the workers build cardboard and plastic tarp camps lacking power, toilets, and running water. These camps are often located in canyons and riparian woodlands "out of sight" of the authorities and legal residents.