Some of my relatives used to live near Tuscon, AZ, which is a microcosm of settler-colonialism and water mismanagement. The Santa Cruz river used to flow year-round through the valley, but today it's a trickle during the dry season:

Most of the Santa Cruz River is usually a dry riverbed, unless the area receives significant rainfall. This was not always the case, but a combination of human errors and natural catastrophes in the late nineteenth century led to the decline of the Santa Cruz.[4] Prior to this, water flowed perennially in a number of places, including along nine stretches in the Tucson area, and the river's banks were lined with cottonwood and mesquite bosques.[5][6] Although there is some disagreement among historians and hydrologists as to what the biggest causes of the river's decline was, contributing human factors included overgrazing, excessive pumping of groundwater for agricultural irrigation and industry, and the construction of dams and ditches.[6] In the mid-20th century, the river's stretch through Tucson dried up completely.

A huge quantity of water is used by a nearby copper mine and the almond farms in Green Valley. Meanwhile, the Tohono O’odham Nation, which used to be self-sustaining with Three Sisters agriculture, now most of their income comes from casinos and tourists visiting the San Xavier Mission (built by native slave labor under Spanish colonial rule).

Also: read The Water Knife