3.1 Geology and Soils
Solana Beach
The Solana Beach receiver site consists of a low tide terrace, which lies in front of coastal cliffs south of
San Elijo Lagoon. The steep coastal cliffs in this area have been continually forming from wave action
cutting against the marine terrace. This process has occurred since the last relative still-stand of sea level,
approximately 6,000 years ago (FRH 1997). The existing receiver site comprises the flat, rocky, shallow
part of the shoreline visible during low tide.
The Solana Beach receiver site is within the Oceanside Littoral Cell and is subject to similar transport
processes as described for South Oceanside. However, this receiver site is not located within the critical
erosional area south of Oceanside Harbor (as identified by the CCSTWS).
Del Mar
The Del Mar receiver site is located within the Oceanside Littoral Cell and is subject to similar transport
processes as those described for the South Oceanside receiver site. The Del Mar receiver site was formed
from sand and rocks that originated from upland erosion. The receiver site consists of a relatively thin sand
layer, which varies in width and lies on rock platform. The receiver site is relatively wide compared to
other receiver sites.
Similar to Batiquitos Lagoon, the San Dieguito Lagoon was formed in the geologic past when the sea level
was lower, the shoreline was farther to the west, and existing streams quickly eroded the exposed marine
terraces. San Dieguito Lagoon is a functioning tidal lagoon.
Torrey Pines
The Torrey Pines receiver site is located on a low tide terrace, which lies in front of coastal cliffs to the
north and south of Los Peasquitos Lagoon. The steep coastal cliffs in this area have been continually
forming from wave action cutting against the marine terrace. The existing receiver site comprises the flat,
rocky, shallow part of the shoreline visible during low tide.
Similar to other lagoons in the region, Los Peasquitos Lagoon was formed in the geologic past when the
sea level was lower, the shoreline was farther to the west, and existing streams quickly eroded the exposed
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Regional Beach Sand Project EIR/EA
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