Upgrading Flood Control Protection In Ventura County

When confronting strong storms, many communities are learning that the flood protection facilities they have been relying on for decades may not be up to the job. The Federal Emergency Management Agency has been gradually re-mapping floodplains across the nation to provide updated information for areas subject to flooding during a one percent annual-chance storm event (i.e. a 100-year storm). This re-mapping effort has shown that many areas previously thought to be protected from a 100-year storm are actually vulnerable to flooding from such a storm. There are various reasons for these changes in flood-prone areas, including more urbanized watersheds and better flood-mapping techniques, but one of the primary reasons is that we now have better information about the sizes of potential storms, thanks to the compilation of decades of meteorological data. This enhanced data is showing us that the potential for large storms in some areas is greater than previously thought.

Aspen has been working with flood control districts across the southwestern U.S. for over 20 years to improve flood protection and flood plain management. An example is a flood protection project Aspen is currently working on for the Ventura County Watershed Protection District (VCWPD) called the SCR-1 Levee Improvement Project. This levee on the Santa Clara River was built by the U.S. Army Corps of Engineers in 1961 and needs upgrades to continue protecting approximately 1,400 structures in north Oxnard from flooding. The existing levee has inadequate scour and erosion protection. The proposed project involves adding soil cement bank protection from the top of the levee to the toedown depth (the toedown is the buried portion of the levee on the river side). The final design may include raising the levee to provide protection during a 200-year flood event. The toedown depth may be extended to meet 200-year flood-flow conditions. Aspen will assist with public outreach for the project, prepare CEQA and NEPA documents, help obtain regulatory permits, and monitor compliance with environmental requirements during construction.

Aspen has provided environmental services to the VCWPD for several levee improvement projects in recent years, including the SC-2 levee along Sespe Creek and the SCR-3 levee, which are currently under construction. Aspen was also recently selected by the VCWPD to provide environmental services for the upcoming VR-1 levee improvement project along the lower end of the Ventura River. Aspen is also currently providing environmental services for flood protection projects to the San Bernardino County Flood Control District and the U.S. Army Corps of Engineers.