Nogales Wash Emergency Flood Fight

LOCATION: The proposed action is located within the vicinity of Nogales, Santa Cruz County, Arizona. 

PROPOSED PROJECT: The U.S. Army Corps of Engineers proposes to undertake flood fights at two locations hereby termed Position 1 and Position 3: 

• P1: Proposed work at P1 entails protection of an approximately 180 foot long exposed section of the International Outfall Interceptor, a major sewer trunk line that conveys untreated effluent from Mexico to the United States for treatment. P1 is located north of Nogales at approximately 31 21' 54" N and 110 55' 50 W, along N Smokey Lane just south of E Calle Sonora, on the east bank. The IOI is currently protected by an earthen berm put in place by local jurisdictions.   Protection measures would entail discharge of native earthen backfill over the exposed sewer line. The backfill would then be armored with riprap or wire mesh and shotcrete.

•  P3:  Proposed work at P3 entails reconstruction of an approximately 300 foot long failed embankment which currently threatens North Old Tucson Highway. P3 is located farther north along Old Tucson Highway where it crosses Nogales Wash at approximately 31 25' 26" N and 110 57' 32". The roadway is currently protected by an earthen berm put in place by local jurisdictions. Preliminary repair plans proposed by the Corps would likely entail placement of compacted native backfill to reconstruct the embankment and placement of riprap for protection.

The proposed action is expected to be underway starting July 29. 

BACKGROUND AND AUTHORITY: Recent flows from summer monsoon rains have eroded embankments at a number of locations within Nogales Wash, exposing and threatening critical infrastructure and property in and within the vicinity of Nogales, Santa Cruz County, Arizona. Additional flows from monsoon rains are expected through July 30.  In response, Gov. Ducey of Arizona requested emergency flood fight assistance from the Corps. The Corps is authorized under Public Law 84-99 (33 United States Code §701n) to undertake emergency operations and provide flood fight assistance.