El Rio Medio Feasibility Study

Critical riparian and cienega habitats have been lost in the region due to water resource changes in Pima County. Congress authorized the US Army Corps of Engineers (USACE) to evaluate environmental restoration potentials along the Santa Cruz River, from the north boundary of the Tohono O’Odham Nation, north to Sanders Road, in Marana. The USACE has divided this evaluation of the river into three separate feasibility studies:

• Paseo de las Iglesias Feasibility Study, consisting of a 7.5-mile reach of the Santa Cruz River and adjacent lands, totaling 5,005 acres, extending from the northern boundary of the Tohono O’odham Nation to Congress Street;

• El Rio Medio Feasibility Study, covering approximately 2,675 acres (about 4.1 square miles) of land, between Congress Street and Prince Road;

• Tres Rios del Norte Feasibility Study, an approximately 18-mile stretch along the Santa Cruz River from Prince Road to Sanders Road, in the City of Tucson, unincorporated Pima County and the Town of Marana, covers an area of about 19,800 acres.

The El Rio Medio Feasibility Study focuses on the Santa Cruz River in Pima County, Arizona. The current study area consists of a 4.5 mile reach of the Santa Cruz River and adjacent lands from West Congress

Street downstream (northwest) to the Prince Road alignment, between Silverbell Road and Interstate Highway 10. This study area encompasses approximately 3,081 acres. The reconnaissance phase of the study was initiated on August 1, 2000. Results indicated interest in continuing the study into the feasibility phase, so Pima County Flood Control District, as the non-Federal sponsor, and the U.S. Army Corps of Engineers initiated the feasibility phase of the study in January 2001. The City of Tucson formally joined the study as a second non-Federal sponsor in December, 2005. The total cost of the feasibility phase is $3,427,000, which is being shared equally (50/50) between the Corps and the non-Federal sponsors.

The primary purpose of the study is ecosystem restoration. Water supply recharge for later recovery and municipal use is a secondary project purpose. The study team will inventory the character of the river and tributary washes, note land uses, summarize habitat quantity and quality, review recreational demand, and evaluate cultural, archaeological and historical resources. Plan formulation commenced on January 18, 2006, with a public meeting to obtain the opinions and comments from interested participants. The study team is currently analyzing an array of 14 single purpose ecosystem restoration (ER) alternatives, and a separate array of five single purpose water supply recharge (WSR) alternatives. The best ER and WSR alternatives will be selected and combined into a final recommended plan using a tradeoffs analysis. At the current time, the study team anticipates having the recommended ecosystem restoration plan by the end of the calendar year. The recommended plan will be presented to the public for comment as the study progresses.

To take a look at the handout of the three feasibility studies along the Santa Cruz River, including dates of meetings open to the public: Click here

For further information, please contact Ann Audrey, at 520-791-4675.