Removing Matilija Dam:
- Why Remove Matilija Dam?
- Objectives
- Benefits from Removal
- Impacts: Habitat
- Impacts: Sediment
- Matilija Dam spilling
Final Design:
- Project Description
- Sediment Management
- Slurry Disposal
- Levees
- Bridges
- Robles Diversion modifications
- Arundo (giant reed) management
- Our Comments
Feasibility Study:
Early Progress:
Background Information:
About the Matilija Coalition:
Flood Control?
On the morning of March 6, after 48 hours of rainfall, flows of over 6,000 cubic feet per second rushing through the "notch" in Matilija Dam created a torrent of water 358 feet wide and 165 feet high.
Although Matilija Dam was constructed primarily to supply water for a rapidly growing Ventura County, it was also proposed to control floods. The "5 year" storm pictured above was minor compared with the 100-year deluge that occurred in 1969. That short duration event dumped 27% of the sediment that rests behind the dam today. It also rendered the 17-year-old reservoir useless for flood control … and it has been ever since.
Images copyright 2001
A. Paul Jenkin
The release valve at Matilija Dam can discharge a maximum of 250 cfs (cubic feet per second). The release pipe is visible at the bottom of this image - 250 cfs looks pretty small against that backdrop!
The graph below shows the history of the flood - a total of 12.65 inches of rain fell in Matilija Canyon. The red line represents the flow of water over the dam spillway, peaking at 6890 cfs (cubic feet per second) on the morning of March 6. The river flow downstream at Foster Park peaked around the same time at just under 20,000 cfs.
