Public Notices

A public notice is the primary method for advising all interested parties of a proposed activity for which a permit is sought. Soliciting comments and information necessary to evaluate the probable impacts on the public interest. Public notices are also published to inform the public about new or proposed regulations, policies, guidance or permit procedures.  

Public Notices published by the Los Angeles District are posted on these three pages. There are two types of Public Notices; Regulatory and Project Public Notices. Comments are due by the expiration date of the public notice. 

Only comments submitted by email or in hard copy format through a delivery service, such as the U.S. Postal Service, can be accepted.   Comments must be submitted to the address listed in the public notice.

Public Notice Manager

SPL-2024-0625-SEA Riverside Levees Rehabilitation Project

Los Angeles
Published June 25, 2024
Expiration date: 7/31/2024

PUBLIC NOTICE: RIVERSIDE LEVEES REHABILITATION PROJECT CHANGES IN DESIGN
Pursuant to the National Environmental Policy Act (NEPA), the U.S. Army Corps of Engineers (Corps) is preparing a Supplemental Environmental Assessment (SEA) for proposed changes in the design of the Riverside Levees Rehabilitation Project to evaluate potential environmental impacts. If the SEA identifies significant impacts that cannot be mitigated to a level that is less than significant, an Environmental Impact Statement would be prepared. If no significant impacts are identified (or if significant impacts can be mitigated to a level that is less than significant), then a Finding of No Significant Impact would be prepared. Concurrently, preparation of an updated 404(b)(1) evaluation is underway pursuant to Section 404 of the Clean Water Act for discharges of dredge material into waters of the U.S.

The Final Environmental Assessment for the Riverside Levees Rehabilitation Project was completed in March 2022. This project would have repaired levees along the Santa Ana River in Riverside and Jurupa Valley by replacing the riprap on the levee faces with grouted stone extending to a scour depth of approximately 17 feet below grade on the Left Levee and 22 feet below grade on the Right Levee. Per the previous design analyzed in the 2022 Final Environmental Assessment, pumps were to be used to dewater groundwater to allow repair areas to extend the grouted stone toe below the groundwater table. However, significant storms in 2022 and 2023 along with associated snowmelt runoff resulted in substantially higher rates of groundwater volume than anticipated, making drawdown below the groundwater table for construction not possible. Costs for an upgraded dewatering system to handle the existing groundwater volumes would be substantial, and as a result, construction was temporarily suspended.

To avoid substantial dewatering costs, the Corps proposes to modify the design to a grouted stone toe that would extend to the depth of the existing water table, approximately 10.5 feet below grade on the Right Levee and 10 feet below grade on the Left Levee. The scour depth below the groundwater table would be protected by launchable stone structures which would be placed atop the riverside face of the grouted stone toes. The typical thickness of the grouted riprap (1.5 to 2 feet thick) and typical slope (1 vertical to 2 horizontal) of the levee would remain unchanged. The geometry and volume of the launchable stone section would vary throughout the repair length for the right and left levees depending on the estimated scour depth. Placement of the launchable stone would be optimized accordingly in the field based on level of encountered groundwater. The length of the proposed repairs are unchanged from the previous design - approximately 8,800 linear feet along the right levee and approximately 4,770 feet along the left levee. Undamaged intervening sections of the federal levee would not be repaired.

Coordination and, if needed, consultation with the U.S. Fish and Wildlife Service will be conducted in compliance with the Endangered Species Act. The project would continue to comply with all requirements of the Clean Water Act, including the Section 401 Water Quality Certification and Stormwater Pollution Prevention Permit. The Corps has completed consultation with local tribes and the California State Historic Preservation Officer on the proposed project pursuant to Section 106 of the National Historic Preservation Act. In addition, pursuant to the Clean Water Act, an updated 404(b)(1) evaluation will be prepared for discharges of fill within waters of the U.S. Comments on this public notice will be accepted from June 25, 2024, through July 25, 2024.  Comments may be submitted electronically to: thomas.f.sentner@usace.army.mil

Figure 1. Proposed levee repairs that do not necessitate dewatering.

Figure 1. Proposed levee repairs that do not necessitate dewatering.