HomeMy WebLinkAbout; ; Beach Reconnaissance Report No 3; 1988-03-01ICN-138
CITY OF CARLSBAD
BEACH RECONNAISSANCE
REPORT NO. 3
FEBRUARY 1988
SUBMITTED TO
CfTY OF CARLSBAD
BY
CHOULE SONU
TEKMARME, IMC.
PASADENA, CA
MARCH 1988
Bi-Monthly Beach Reconnaissance
February 5, 1988
Executive Summary
The sand veneer on the beach has shrunk further from the previous inspec-
tion which took place on December 28, 1987. The continuous sandy beach
south of Oceanside Harbor is now only about 1 mile long, as compared to the
3-mile length two months ago. As a result, the underlying cobbles make
their appearance much closer to Oceanside Harbor, even as close as at
Oceanside Boulevard. The dominant material on the coastline south of this
point, as far as Moonlight State Beach at Encinitas, is essentially cobble.
The storm waves of January 17-18, 1988, in which high waves occurred in
conjunction with a high tide, loosened the riprap fronting the beach-front
houses at Oceanside, scattering some smaller rocks from the riprap on the
beach. The bluff in front of a condominium complex south of Buena Vista
Lagoon collapsed during the same storm. While removing the beach sand and
eroding the bluff, the storm waves, aided by high tide, pushed cobbles fur-
ther up on the beach, piling them up against the base of the seawall,
bluff, and riprap. The shoulder of Carlsbad Boulevard at Encinas Creek
Outlet was eroded by high waves, but the damage at this low elevation was
surprisingly minor in severity since cobbles which are abundant on the up-
per beach tended to reduce the runup energy of the waves.
The inspection at this time also revealed that the beaches in the study
area probably represent the leanest status in terms of subaerial sand
volume. There were indications that sand was returning to the beach.
Patches of sand were observed at a number of locations along the low-tide
shoreline, gradually overriding the seaward edge of the cobbles while ad-
vancing up the beach.
Note: Prior reconnaissance
October 13 and 21, 1987
December 28, 1987
February 5, 1988
WISCONSIN AVENUE (OCEANSIDE)
The beach has all but disappeared, so that swashes are clashing
directly at the riprap. The southern edge of the fillet south of
Oceanside Harbor is seen in the farground on the upper photo.
February 5, 1988
OCEANSIDE BOULEVARD (OCEANSIDE)
Cobbles, not seen here in summer, dominate the base of the
riprap. The beach has lost sand considerbly.
February 5, 1988
CASSIDY STREET (OCEANSIDE)
Swash front is directly on the riprap. Lots of cobbles have been
washed up into the gaps between the riprap stones.
February 5, 1988
MOUNTAIN VIEW DRIVE (CARLSBAD) (BUENA VISTA LAGOON OUTLET)
The bluff in front of a condominium complex south of Buena Vista
Lagoon collapsed during the recent storm. Lots of cobbles have
been pushed on the upper beach by strong swashes during the
storm, almost burying the rock foundation. Sand is very scarce.
February 5, 1988
BEECH AVENUE (CARLSBAD)
The beach is dominated by cobbles, which are piled up against the
riprap. Sand exists only beyond the water's edge.
February 5, 1988
PINE AVENUE, CARLSBAD (NORTH END OF NEU SEAWALL)
Storm waves have pushed cobbles against the seawall, completely
covering its toe. Some sand has returned to the beach.
February 5, 1988
ACACIA AVENUE, CARLSBAD (CARLSBAD STATE BEACH)
Cobbles on the upper beach have buried the rock foundation which
was seen exposed in December at this location.
February 5, 1988
AGUA HEDIONDA LAGOON (CARLSBAD)
The beach in front of Agua Hedionda Lagoon has now lost all the
sand which existed on the upper beach two months ago. This prob-
ably occurred during the January 18 storm. Sand is now returning
to the shore slowly, as indicated by a narrow strip of sand along
the water's edge.
February 5, 1988
MANZANO DRIVE (CARLSBAD)
Cobbles dominate this beach, essentially unchanged from December.
February 5, 1988
ENCINAS CREEK OUTLET (CARLSBAD)
A recent storm (January 18) damaged the shoulder of the south-
bound lane of Carlsbad Boulevard. Sand is almost non-existent on
this beach.
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February 5, 1988
POINSETTIA LANE (SOUTH CARLSBAD STATE BEACH)
Cobbles are dominant on this beach, but sand is seen returning to
the shore in isolated patches here and there.
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February 5, 1988
BATIQUITOS LAGOON OUTLET (CARLSBAD)
The beach is covered fully with cobbles. The entrance to the
lagoon remains closed.
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February 5, 1988
MOONLIGHT STATE BEACH (ENCINITAS)
A fully cobble beach, unchanged from December.
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