Local officials called in Army Corps of Engineers technical crews among others to provide recommendations on just what could be done to prevent a potential sewage spill and structural failure of the wash walls, railway, and the bridge.
 
Julie Martinez, a resident engineer from the Corp’s Tucson Resident Office and John Taylor, a Project Engineer, traveled Nogales to meet with local officials, emergency response teams and engineers with the International Boundary Water Commission (IBWC) to discuss and implement a plan to prevent further erosion and protect the sewage channel.
  
Martinez recommended laying large angular granite rock to add stability to the sand-bagging process already underway in the wash. Grout-covered sandbags were set along the eroded areas above the sewer line and a berm of sandbags was constructed to divert the flow in the wash away from the west wall.  She also insisted that a geotechnical engineer should inspect the west wall of the wash.
 
“Another storm was predicted for that afternoon,” Martinez said. “Lookouts along the south and in Mexico stood watch – ready to signal any surge of water. Men and equipment were in the wash and everyone was concerned with their safety- and a swamped dump truck or dozer would add to the problem. If another pulse (flash flood) caused more erosion, the wall could collapse and block the wash. The railway could also be compromised, and worse case scenario, the nearby prison flooded necessitating an evacuation.”
   
By the evening of Aug. 27, the immediate danger had passed, but the instability of the west wall remained. Col. Thomas H. Magness IV, District Commander for the L.A. district, said he was pleased with the response members of his team provided to the city and county.

"The situation in Nogales was critical and we did everything we could to help,” Magness said. “We deployed our A-Team to provide technical assistance to include our Chief Engineer, Bob Koplin, and some of his staff engineers.  Together they have provided the technical data that has allowed the city, state, and local entities to develop some short term solutions.  We worked with the (IBWC) and our Congressional delegation, all of whom were very much engaged in this issue, to develop a longer term way ahead.  I am real proud of the effort from Bob Koplin and his engineers and believe that, together with the rest of the team, we have provided some measurable, meaningful relief to the citizens of Nogales," said Magness.

The damaged wash area is approximately four miles south of the Corps’ current flood control project in Nogales.  Construction, consisting of grouted stone bank stabilization, began in 2006 on the Chula Vista Channel.  Future flood control efforts include further bank stabilization in the wash, two bridges, replacement of the sewer line and the construction of the diversion channel that will protect the Chula Vista community and a historic fire station.

Public law 84-99 authorizes the Army Corps of Engineers to provide technical and direct assistance to local governments for emergency repair and restoration of flood damaged or destroyed flood control works.  Corps assistance is considered a supplemental source when local government funding for these efforts is exhausted.
 
For detailed information on the Corps emergency assistance role in flood control please visit our national website at http://www.usace.army.mil/cw/cecwhs/em/cecwhs_em.html.