San Xavier North Dump Stormwater Control
Location: San Xavier District, Tohono O’odham Nation, Arizona
(Project “stats” off to the side):
-6,000 ft of Channel and Berm
-24 Containment Ponds
-215 acres of floodplain modeled
–24” D50 Rock Riprap Armoring
The natural watercourse of several braided washes caused significant incising and erosion of the existing containment earthworks which led to onsite waste rock stormwater comingling with offsite stormwater. A channel and levee system was designed to contain the waste rock runoff and safely divert offsite stormwater around the waste rock dump. The levee was armored with large riprap to protect against the sediment–laden highly erosive flows that occur onsite. In-depth hydrologic and 2D hydraulic modeling was performed to estimate peak flows and design the levee system. The end product for the client was a cost effective design using on-site materials that complied with requirements set forth in the Section 404 permit issued by the U.S. Army Corp of Engineers.