The Malibu Creek Floodplain/Wetland, circa 1892

Note the ponding held back by the Pacific Coast Highway, circa 1938

The present day Civic Center is an impaired floodplain/wetland because of 10' to 20' of landfill, as well as commercial development placed on top. We hope the acquisition of the Chili Cook Off property (center green open-space) will be the beginning of the restoration process.

From this photo you can see the close proximity of the two shopping centers dangerously close to the Creek and Lagoon and in the path of a 50-year storm.
the Adamsons had rip-rap placed along the west streambank. Compare it to the natural state of the east bank.

The California Coastal Commission issued a temporary permit to allow rip rap to be place on the west end of the creek bank to buffer local businesses from flooding. The rip rap still remains.

Earthquake Faults in the Malibu Center
Seismic Hazards Zone 2001 and State Geological Maps
The following is provided by
Don Koweleski, Geologist, Malibu

click here to see larger image

This map was prepared as part of the state geologist's mapping of all active faults in California in accordance with the Alquest-Priolo Act. 

The geologists designated a special study fault zone were they have sufficient evidence to demonstrate recent geologically activity (last 11,000 years) and where the fault trace is sufficiently well defined. 

They could not map a special study zone where it is concealed by young sediments.  

Darker dashed lines indicate where there are faults, lighter dashed lines indicate where faults are interpreted to exist, solid lines indicate where faults are visible and dotted lines where faults are concealed.

Earth quake history is based on trenches that were excavated in several places in Malibu.  The soils that were offset by fault movement were interpreted to be the result of a past earthquake that caused ground surface rupture.  Typically a magnitude of 6+. 

I observed offset soils at Winter Mesa south of Pepperdine, and offset soils in the vicinity of the Pepperdine lakes.  Similar offsets were observed by others in a ridge between Latigo Canyon and Solstice Canyon.  Dating of the offsets was performed by specialists in soil stratigraphy and they opined that the offsets were about 6000 to 10,000 years old.

The Malibu Coast fault is a branch of the Santa Monica Mountains Thrust Fault System. This fault system is responsible for the uplift of the Santa Monica Mountains. 

There are some studies that suggest the most recent movement on the system is about 2000 years ago.

By all standards, the fault system is active but the stress buildup is significantly slower than the San Andreas fault, which has an average recurrence interval of major earthquakes with ground surface rupture every 135 years.

click here to see larger image

The State mapping of Fault Hazard Zones places all of the civic center within a liquefaction hazard zone. 

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The following is from the Natural Resources Plan:

"2.5 SEISMICITY
A high degree of tectonic activity exists in the area and local watersheds have been uplifted by as much as 24.9 feet per 1,000 years. Although the 1994 Northridge earthquake was not centered in the watershed, Oat Mountain in Ventura County was uplifted 18.1 inches. Uplift is partly counteracted by erosion, which lowers the landscape. The maximum extrapolated rate of denudation, measured
over the available period of record, is 7.6 feet per 1,000 years, adjusted to a drainage area of 109 square miles (Scott and Williams, 1978).

The high rate of seismic activity is partly responsible for the landslides and slips throughout the watershed. Most of the lands are steep, with relatively shallow soils over bedrock. These soils slip readily, as evidenced by the many landslide and slip surfaces visible on the hill slopes. Earthquakes during periods of soil saturation cause the soil slippage to radically increase because of liquefaction
along the contact zone, and cause landslides or slips occur almost instantaneously."

Home - Introduction - History - Wetland Restoration - Studies - Videos - Organization

This is the Malibu Center Topo Map. It shows the high water table area indicating the historical wetland. Also, a tidal lagoon was indicated at the west end, circa 1899. SEE LARGER IMAGE
Dr. Terry Huffman refers to the topo map that indicates the historical wetlands covering hundreds of acres. City Council member Tom Hasse and Joan House indicated there were only 2 acres. See the video

A through F of first documentation of historical wetland evolution from the UCLA 2000 Study, pg 2-3 CLICK HERE TO SEE LARGE IMAGE

This is the image City Council members referred to during the political campaign of 2004. Did they make a mistake unintentionally by not referring to image "A"? CLICK HERE TO SEE LARGE IMAGE. See images C thru E in the UCLA 2000 Study pg 2-3

CLICK HERE TO SEE LARGE IMAGE




FEMA's 100-year flood plain map of the center of Malibu. SEE LARGER IMAGE
This 1995 50-year flood brushed up under the Pacific Coast Highway bridge. CLICK HERE TO SEE THE VIDEO Imagine the impact of a 100-year flood, which is what any development is supposed to sustain according the Malibu's General Plan.

The 1995 50-year flood inundated the Cross Creek shopping center and the Country Mart.
Looking toward the creek from the Chili Cookoff property, you can see that both shopping centers, the Country Mart in the foreground and the Cross Creek shopping center are covered by one to two feet of flood water entering from the creek. See the video.