The U.S. Bureau of Reclamation (USBR) is requesting §401 CWA Water Quality Certification from the Environmental Protection Agency. The §401 CWA Water Quality Certification will authorize maintenance activities on the Lower Colorado River to remove sediment build up that poses a threat to navigation and restricts river flow.
For Further Information Contact
Elizabeth Goldmann (email@example.com), Wetlands Section (WTR-2-4), U.S. Environmental Protection Agency, 75 Hawthorne St., San Francisco, CA 94105; (415) 972-3398
The USBR is proposing maintenance activities at the Vidal Wash Fan. This Vidal Wash Fan is located on Colorado River Indian Tribe’s (CRIT) land along the lower Colorado River’s Parker Division, south of Parker, Arizona. The maintenance plan would consist of removing sediment built up that is creating bankline erosion, poses a navigation hazard, and restricts river flow.
Vidal wash fans have been targeted for removal during the low water period (December – March) of the river. Approximately 58, 620 cubic yards of mostly sand with some gravely material will be excavated from the wash fan area to a maximum of 8 feet below the navigational level of the river for a portion of the wash fan. The project surface area covers about 4 acres. No wetland vegetation will be impacted during excavation activities. Existing roads would be used to gain access to the wash fan and stock pile site. Material would be removed using land based equipment. Material will not be stockpiled in the wash fan area or discharged into the main river channel. It will be transported to an off-site upland location. Option 1 -Agnes Wilson Quarry Stockpile site; Option 2 – Adjacent upland site on CRIT land; Option 3 – Placed next to existing stockpile site on CRIT land. Approximately 4 to 6 weeks of construction activities is required for wash fan removal. Prior to activities commencing, coordination with CRIT will be conducted.
Wash fan removal is a reoccurring maintenance activity undertaken by USBR under the authority of the Colorado River Front Work and Levee System Act of 1946 (amended) for the purposes of controlling floods, improving navigation and improving the flow of the Colorado River in Arizona, Nevada, and California. Alluvial material discharges into the river during precipitation events forming wash fans. Wash fans are identified for removal by USBR when river flows are modified causing bankline erosion or when the wash fan restricts flow, reducing channel capacity and/or causing a navigational hazard.