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 Solana Beach Coastal Preservation Association
August 20, 1998
Project No. 1831
Page 29
5.1
Historical Analyses
Historical data often include maps, charts, photographs, survey notes, reports, newspaper
clippings and eyewitness accounts (Fulton, 1981). Useful historical information about
coastline changes in San Diego County extends back to the later part of the 19th Century,
and reasonably accurate climatological data dates back to the early 1800s.
Stereoscopically-paired vertical aerial photographs (typically at a scale of 1:24,000) are
available from 1928, and good-quality, low-angle oblique photographs (at a scale of
1:2400) date back to 1954. Ground-level, close-up photographs, which are usually the
most useful to assess site-specific changes in the coastline, are not abundant, but locally
are available from the personal collections of private individuals and from historical
societies and museums. Successive ground or aerial photographs, dated drawings, or
even paintings that show former coastal configurations, are very useful to assess short-term
(historical) rates of erosion (Bird, 1985).
Summary conclusions from the 1960 USCOE report on ABeach Erosion Control,
Cooperative Study of San Diego County, California,@ prove insightful regarding early survey
work in the site vicinity.
Batiquitos Lagoon to Soledad Way - Examination of the surveys indicates that
the mean high water shoreline from Batiquitos Lagoon to Soledad Valley was
essentially unchanged between 1887 and 1934. The 1957 mean high water line
is slightly seaward of the 1934 line at Moonlight Beach in Encinitas. At the
mouth of the San Dieguito River near Del Mar, the 1957 mean high water line is
unchanged from the 1934 location. It is believed that no serious bluff erosion
occurred along this section of the coast between 1887 and 1934.
The mean lower low waterline of 1934 is about 100 feet shoreward of the 1887
line along this entire length of shore from Batiquitos Lagoon to Soledad Valley
and the 1957 mean lower low waterline, in general, follows the 1934 line. The
1887 and 1934 surveys were examined and no difference could be found in the
location of the bluff lines as no serious bluff erosion occurred along this section of
coast between 1887 and 1934. The high bluffs, which back the narrow beach
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