The City of Simi Valley has initiated a citywide project to update the National Flood Insurance Program (NFIP) floodplain mapping. The current mapping relies on rainfall data and mapping technologies that are over 30 years old.

Phase One - Tapo Canyon Creek Letter of Map Amendment

Effective October 22, 2024

On June 10, 2024, FEMA has issued a Draft Letter of Map Amendment (LOMR), 23-09-0719P, which will remove significant portions of the floodplain within the blue border of the map below. However, the floodplain will expand in a few locations onto properties that had been overlooked previously.

As a result of this LOMR, the limits of the floodplain will be significantly reduced and will result in the following:

• 1,903 properties will be removed from the SFHA
• 223 properties will see the mapped flood depth decrease
• 53 properties will have a portion newly mapped into the SFHA

FEMA will publish notices of the proposed changes in the Ventura County Star on June 17 & 24, 2024. This will offer any interested party 90 days to submit an appeal based on scientific or technical data. If FEMA has not received any appeal, the LOMR will become effective on October 22, 2024.

This Draft LOMR includes portions of the Arroyo Simi and tributaries as follows:

• Arroyo Simi – Beginning at First Street to a point downstream of Royal Avenue
• Dry Canyon Channel – From the Arroyo Simi to a point downstream of Cochran Street
• Erringer Drain Channel – From the Arroyo Simi to a point downstream of Kearney Avenue
• Runkle Canyon Channel – From the Arroyo Simi to a point downstream of Arcane Street
• Tapo Canyon Creek – From the Arroyo Simi to Walnut Avenue.

A copy of the Draft LOMR can be reviewed at the City of Simi Valley at 2929 Tapo Canyon Road, Simi Valley, CA 93063.  If you have any questions or concerns about the proposed project or its effect on your property, you may contact you may contact Brent Siemer, Floodplain Manager for the City of Simi Valley, at bsiemer@simivalley.org, or by phone at (805) 583-6805. 

Phase Two – Citywide Physical Map Revision (Oct.2024)

The next phase of this project will require much greater time and effort to accomplish. Therefore, the City has hired the local civil engineering firm of Kasraie Consulting to develop the floodplain modeling and work with FEMA to process a Physical Map Revision (PMR). Kasraie Consulting has extensive experience studying and mapping flooding in the City, including developing the City’s Master Plan of Drainage. Kasraie Consulting is led by Hassan Kasraie, PE, CFM, an experienced local water resources engineer with decades of experience helping to reduce flooding in Ventura County. The Kasraie Consulting team also includes subconsultant River Focus who is a trusted partner with extensive experience working with FEMA. The Kasraie Consulting team is currently working to develop the floodplain computer models that will be used for floodplain remapping in the City.

In the future, FEMA and their consultants will review the PMR submittal and ultimately prepare all new maps and revise the Flood Insurance Study to document the changes. The anticipated timeline for completion of this work is 2-3 years. Updates to the status of this phase of work will be made periodically.