Resolution 270-1979
RESOLUTION if
270-1979
WHEREAS, the BOARD OF COUNTY COMMISSIONERS of MONROE County,
Florida, has received an application from Don C. Unger, to construct:
170 line ft. of riprap below MHW along an open-water and
artificial canal shoreline and backfill to regain eroded upland
property. Approximately 272 cubic yards of clean fill (riprap and
back-fill) is estimated to be necessary, 1/3 of which or about 90
cubic yards would be placed below MEW.
Riprap, as proposed, will be placed about 10' to 12' below MHW
along the length of the open water shoreline and based on a verbal
revision (received from Donald Unger on 10/5/79) about 6-8' below
MHW on the canal shoreline. These distances will restrict the
riprap to landward of existing seagrasses. A crane will be utilized
to place riprap and a dozer will be used to level fill transported to
the site over upland roads.
The applicant also proposes to excavate a boat ramp with the upland
dimensions of about 25' wide x 25' long sloping to a depth of -6.5'
MLW. About 79 cubic yards of spoil would be removed and presumably
used as backfill on the uplands. As this ramp is to be located on
the canal shoreline it requires no F.D.E.F. permit as stated in
Chapter l7-4.04(10)(e).
Silt barriers, as stated, will be used in dredging and filling
operations, if necessary.
The site is located in a residential subdivision created by the
excavation of an upland canal system years ago and the placement of
the spoil on the uplands. North and south of the subdivision on the
west side of Big Pine Key are natural mangrove fringed shorelines.
The area is on Pine Channel as it narrows, shallows and passes between
Big Pine Key and Howe Key. The canal system contains numerous dead-end
canals but water quality is maintained by a combination of its
orientation of entrances to the west, extensive seagrass vegetation
on the bottom of the canals and low development (less than 25%) of the
area. The adjacent channel contains seagrass communities as most
of its benthos. The subdivision is contained within the boundaries
of the Key Deer National Wildlife Refuge.
The project site is a corner lot where an artificial canal system opens
into Pine Channel. The shorelines have always been irregular probably
due to the lack of fill resulting from no offshore access dredging.
The shorelines have eroded back somewhat and on the open-water side
consist of a sloping, rubble bottom that grades into softer sediments
and turtle grass (Thalassiatestudinum) at its toe about 9-12'
waterward of MHWat a depth of about -2 to -3' MLW. The algae
Batophora and Acetabularia are found along the bottom edge of the slope
as is Cuban shoalgrass(Halodule wrightii). Observed along this
shoreline were upside-down jellyfish (Cassiopeia), holothuroidean
and stelleroidean echinoderms, gastropids, and killifish (Cyprinodon-
tidae), pinfish (Lagodon rhomboides) and mojarras (Gerreidae). Net
samples in the turtle grass produced numerous carridean crustaceans,
tubiculous polychaetes, gastropods, and Cyprinodontids. The canal is
vegetated throughout by turtle grass, shoal grass, manatee grass
(Syringodium filiforme) and various epiphytic algae. The canal at
this site is believed to be about -8 to -10' MLW in depth. The
dredged canal ends immediately offshore and surrounding depths are
a maximum of -3' to -4' MLW. The canals in this system are about
50' wide throughout but at the site, due to the irregular shorelines,
the canal increases to about 60' wide.
APPROVED ON
1l-~o-'11
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The canal shoreline is also sloping rubble and becomes vegetated
at about 7-8' below MHW with Penicillus, Halodu1e and Tha1assia.
The canal shoreline is meandering as is the open-water side.
Uplands are essentially barren with a few Australian pines (Casuarina)
and immediately above MHW can be found scattered sea ox-eye-daisy
(Borrichia), glasswort (Sa1icornia) and small buttonwoods (Conocarpus
erectus).
The applicant proposes to place the riprap to the landward edge of
the subtidal seagrass vegfmtion on the open-water and, as revised, on
the canal shoreline. The placement of this riprap is not expected
to result in any adverse impact to this vegetation due to the low
energy situation of the shoreline and depth of grasses in this zone
and will, in fact, create valuable littoral habitat. It has been
observed at other locations on the west side of Big Pine Key where
seawalls and riprap have been placed below MHW, there are existing
healthy turtle grass beds immediately adjacent to the new substrate.
It is not advocated that shorelines be commonly riprapped in such
a manner but as this is an eroded, artificial fill area with
essentially no shoreline or intertidal vegetation, the benefits gained
(erosion protection, habitat creation) outweigh the detriments.
BE IT FURTHER RESOLVED, by the BOARD OF COUNTY COMMISSIONERS
of MONROE County, F11rida, that said BOARD hereby given its approval
for the construction of the above mentioned project.
RESOLVED this
20th
day of November, 1979, at a Regularly
scheduled Meeting.
BOARD OF COUNTY COMMISSIONERS
MONROE COUNT- FLORIDA
".
BY
ATTEST _-~) ~
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