Santa Clara River Hydraulic Analysis / Floodplain Mapping / Bank Stabilization

Los Angeles and Ventura Counties, CA

For over 20 years, PACE has been one of the primary consulting engineers providing planning and design of enhancements to the Santa Clara River throughout its reach in Los Angeles and Ventura Counties to support development and flood protection objectives.  PACE’s role includes hydrologic, hydraulic, sediment, and runoff water quality modeling and analysis; Conditional Letter of Map Revision (CLOMR) / Letter of Map Revision (LOMR) processing; riverbank protection design; water quality management; and sediment transport management. During this time, PACE has facilitated the groundbreaking use of soil cement as a more cost-effective and environmentally sensitive means of providing flood control along the river.

Soil cement bank protection provides a unique multi-function solution for challenging flood protection problems. Environmentally, soil cement reduces the import of non-native raw materials to the job site by utilizing the native soils of the area. In addition, soil cement has been shown to require less maintenance and less time and cost to install.

PACE has worked with the Los Angeles County Public Works Soil Cement Technical Committee to provide supporting information for soil cement suitability as a Public Works standard. Data from many existing projects in other jurisdictions was collected, compiled, and evaluated, then presented to Public Works for consideration. Once the pilot project was approved, PACE conducted several in-house design seminars regarding soil cement design and construction material inspection.

To date, PACE has planned, designed, and managed construction of more than 60,000 linear feet of soil cement bank stabilization. The success of these projects is due to a combination of innovative engineering, use of cost-effective design methods and construction materials, and participation from multiple stakeholders including Los Angeles County Public Works, California Department of Fish and Wildlife (CDFW), and U.S. Army Corps of Engineers (USACE).

Key Features:

• Sediment yield / sediment transport analysis
• Preparing hydrologic / hydraulic documentation reports
• HEC-RAS, HEC-2, HEC-GeoRAS, HEC-1, SAM, HEC-6T
• Sedimentation engineering and geomorphology
• Floodplain analysis
• Geographic Information System (GIS) spatial analysis
• Naturalized (soil cement) environmentally sensitive bank protection solution
• Supported Los Angeles County Public Works’ evaluation process leading to the adoption soil cement as an approved bank protection method