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0049im.jpg){kind=tracking} The channels within the Carpinteria Marsh have been maintained for flood control purposes by
the SBCFCD. Sediment contained within the channels is considered a potential source of beach
fill material. As with the Goleta Slough, the sediment is removed via dredge every three to four
years. However, the volume is less than that of the Goleta Slough and is estimated to be
approximately 10,000 to 40,000 cy. Only a small fraction of this may be beach compatible
(6,500 cy) according to SBCFCD (Karl Treiberg, County of Santa Barbara, personal
communication, December 2000).
In addition to channel maintenance, the SBCFCD is
investigating Carpinteria Marsh inlet improvements where up to 14,000 cubic yards may become
available for beach fill.
Callegus Creek in Ventura County yields of large quantity of sediment. Historical records
indicated that in the Lower Callegus Creek from Highway 1 to Hueneme Road Bridge
approximately 300,000 cy is removed every four to five years.
The Matilija Dam, located on the Ventura River, is presently being studied to look at the
feasibility of decommissioning the dam. It is estimated that there is six million cubic yards of
sediment trapped behind the dam. A Sediment Management Plan is scheduled for completion in
2001 to determine the physical and chemical properties of the sediment (Flynn 2000). It is
potentially a very large future source of sediment for BEACON.
4.1.3
Landslides
Landslide deposits are another potential source of sediment for the beach enhancement program.
Caltrans Districts 5 and 7 have expressed interest in working with BEACON to place beach
quality material generated from landslides on the beach. Landslides generally occur during the
winter-wet season. Caltrans is the California state agency responsible for planning, designing,
building, operating, and maintaining California's state highway system including rail and mass
transit. Therefore, when landslides occur near roadways and railroad tracks, Caltrans is
responsible for removing the material and disposing of it properly. It is estimated that in Ventura
County, approximately 200,000 to 250,000 cy of sediment is generated annually from such
landslides (Wayne Johnson, Ventura County Maintenance Area Manager of Caltrans District 7,
personal communication, December 2000). In Santa Barbara County approximately 10,000 to
100,000 cy are produced annually (Nirenberg 2000). No information is available at this time
regarding the proportion that is beach compatible.
4.1.4
Other Sources
It is impossible to accurately estimate the volume of material that may be available from one year
to the next from unforeseen upland development or other projects. However, additional sources
may become available during the five-year program life. These include, sediment generated from
upland construction projects, wetland restoration projects, and other unidentified sources. These
sources should be included in the program due to the possibility of their existence.
4.2
CRITERIA OF BEACH FILL SAND SOURCES
Criteria for beach fill sand sources are specified to enable BEACON to implement projects in
accordance with environmental guidelines established by the State and Federal government, as
4-4
Moffatt & Nichol Engineers
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