Wednesday, February 8, 2023

January 2023 Flood Overview

Aerial images provide perspective on how the Ventura River responds to flood.  The wide floodplain is typical of high sediment yield watersheds, featuring braided channels that shift with each major flood event.  The flood of January 9, 2023 ripped out large areas of vegetation and "re-set" the floodplain.   These images were taken shortly after the storm and are organized downstream to upstream. 


Ventura River near Foster Park - flows overtopped the bank near the City of Ventura Nye Wells


Flooding near Foster Park - several homes were damaged 

 
Ventura River near Oak View - stream bank erosion damaged the Ventura River Trail and broke the main sewer line - combined with a similar broken line on San Antonio Creek 14 million gallons of sewage were estimated to have spilled into the river closing beaches for more than a week

Ventura River downstream of Santa Ana Bridge

Ventura River at Santa Ana Bridge - the bridge was recently replaced widening the river to accommodate high flows and future increased sediment transport with Matilija Dam removal

Live Oak levee upstream of Santa Ana Bridge - similar damage occurred in the 2005 flood - this levee is currently in final design for reconstruction as part of the Matilija Dam Ecosystem Restoration Project

Ventura River at Highway 150 bridge

Ventura River above Highway 150
the Ventura River Preserve protects open space for recreation and  natural floodplain management 

Robles Diversion - the flood filled the forebay with sediment and breached the timber cutoff wall - Casitas Water District quickly implemented emergency repairs to restore water diversions to Lake Casitas

 
Ventura River upstream of Robles Diversion
stream bank erosion exposed and broke the Matilija Conduit which supplies Casitas water to property owners upstream

Ventura River near Ojala - this view looking upstream includes Matilija Canyon and Matilija Dam - flood flows severely damaged the Camino Cielo crossing which provides access from Highway 33 to several properties - a new bridge is being designed as part of the Matilija Dam Ecosystem Restoration Project


Photo published in the Ojai Valley News shows the extent of debris flows on Highway 33 - the Highway was closed indefinitely for repairs 


Damage to Highway 33 North Fork Matilija Creek - photo published by CalTrans



(all photos courtesy Rich Reid rich@richreidphoto.com except where noted)