4.4 Biological Resources
of the receiver site and varies considerably from non-vegetated low relief benches and rock, low relief
vegetated with opportunistic species, to more developed areas that support surfgrass. Intertidal surfgrass
was mapped in January 2000 north of the receiver site at "Pill Box" reef (offshore of Helix Avenue in
Figure 4.4-8), near Tide Park and at "Table Tops" reef (offshore Ocean Street in Figure 4.4-8). Nearshore
hard substrate includes low relief benches that start around the entrance to Fletcher Cove and extend
further north, and higher relief areas near Tide Park and "Table Tops" reef. Nearshore reefs also occur
offshore the southern end of the receiver site and extend further south. Historically, giant kelp has had a
relatively high persistence offshore and north and south of the receiver site at depths greater than -25 feet
MLLW, and less persistence at shallower depths. Kelp canopy was not present in the vicinity of the
receiver site 1999 probably due to El Nio associated losses.
Pill Box reef, which is closest to the site, is not predicted to be a sand depositional area. Less than four
inches of sand above the average profile is predicted under above average wave conditions, and no
measurable persistent sedimentation is predicted under average waves conditions. Predicted sand depths
are well within the range of historical average seasonal differences in sand depth. Furthermore, no
substantial burial of the reef is expected given that predominant relief heights range between one and four
feet. No measurable persistent sedimentation is predicted for the intertidal surfgrass bed at Pill Box reef
and there would be no significant project-related impact.
No measurable persistent sedimentation is predicted for intertidal surfgrass beds located near Tide Park
or at Table Tops reef. Similarly, nearshore reef and historic kelp bed areas near Tide Park and Table Tops
reef are predicted to receive negligible (about two inches) or no persistent sedimentation. Additionally, no
persistent sedimentation is predicted for intertidal, nearshore reef, and historic kelp bed areas offshore and
to the south of the receiver site. Impacts to these resources at these locations would, accordingly, be less
than significant.
As is seen in Figure 4.4-8, the nearshore area is characterized by numerous reefs, some with vegetation
and some without. As with all the nearshore zone, habitat at this location is subject to the dynamic forces
of nature. Areas that were obscured by kelp in January 2000 during the side-scan sonar survey were found
to be almost void of kelp when divers surveyed the same area in March 2000. Storms had removed much
of the kelp from the nearshore reef and only a few giant kelp plants had scattered occurrence on reefs less
than -25 feet MLLW. The winter reef heights range from one to two feet (mainly one and one-half foot)
and summer heights would be expected to be approximately one foot higher based on the historical average
differences in sand depths between winter and summer seasons. Model-predicted, worst-case sediment
Regional Beach Sand Project EIR/EA
Page 4.4-35
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