Bordered by sand dunes and barren mountains, it was an uninhabited wasteland until 1901, when the Imperial Canal was opened and diverted Colorado River water into the valley through Mexico. Floodwaters in 1905–07 destroyed the irrigation channels and created the Salton Sea (now maintained by irrigation runoff).

Farmland consists of very fertile, alluvial deposits derived from the Colorado River flood plain. Well-drain loams and silty loams are the preferred soil types. Since the area was developed in near the turn of the century by water & and land companies, the fields were marked off in sections (1 mile x 1 mile).

In 2021, Imperial County, CA had a population of 180k people with a median age of 290 and a median household income of $49,078. Between 2020 and 2021 the population of Imperial County, CA declined from 180,580 to 180,051, a −0.293% decrease and its median household income grew from $46,222 to $49,078, a 6.18% increase.

The 85-year average annual rainfall is 2.93 inches (74 mm) with June being the driest month.