At the confluence of the Rillito, Pantano and Tanque Verde Creeks water once flowed perennially. The river channels were lined by a continuous oasis of trees containing great strands of mesquite, sometimes reaching 60 feet in height and trunks a foot and a half in diameter, intermingled with cottonwoods, elderberry, hackberry, walnut and ash. The dense vegetation of riparian wetlands were homes for a multitude of birds and animals.
Many people built lives here. And they were all drawn to the area to take advantage of one single resource: the abundance of water.
The Hohokam built their villages and sustained their agricultural fields for over one thousand years. The Anglo and Mexican settlers built irrigation ditches to draw water to their farms and ranches. The U.S. Army built Fort Lowell and argued constantly with their neighbors over land and water rights. And when Fort Lowell was abandoned Mexican immigrants rebuilt the army structures and made their livelihood by cutting and selling wood. The Mormons established dairy farms and raised all of the crops required to feed their growing community.
By 1946 the land was barren. Everything had been cut for firewood or building material. Wells were beginning to falter and irrigation ditches empty. The riparian environments disappeared and the rivers were transformed into dry washes. For the first time in its history the presence of water was no longer connected to the importance of the land.
In 2004 the US Army Corp of Engineers conducted a study to solve the environmental degradation, flooding and related land and water resource problems. Their planning objective: to restore the riparian communities within the river corridor by increasing wetland habitat and diversity. The total first cost estimate was $66,657,000 and the total annual cost estimate was $1,243,357.
Rillito River, Pima County, Arizona El Rio Antiguo Feasibility Study U.S. Army Corps of Engineers Los Angeles District South Pacific Division October 2004
Environmental Restoration Projects in Arizona: The U.S. Army Corp of Engineers’ Approach Final Report June 2005
Sharon B. Megdal, PH.D. Director, Water Resources Research Center University of Arizona, Tucson, AZ