HomeMy WebLinkAboutCOM 0633.000 2000-2002 ITEMS FOR PERUSAL
AND DISCUSSION
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ANTICIPATED MEETING WITH:
GENERAL COUNCIL OF THE COUNTY OF HAWAII
THE FOLLOWING REPORT IS INTENDED TO PRESENT TO THE
MEMBERS OF THE COUNCIL AND ITS DEPARTMENTAL AFFILIATES
TO BE COGNIZANT OF THE NEED FOR CONSERVATIVE EFFORT BY
ALL IN (1) BEAUTIFY THE ISLAND OF HAWAII AS AN ATTRACTION
FOR VISITORS TO INCITE 'TOURISM'. THE SLOGAN, "MAKE HAWAII
BEAUTY" IS RECOMMENDED. (2) THE DEPARTMENT OF RESEARCH
AND DEVELOPMENT SHOULD BE NAMED AS ITS TITLE TO READ:
"RESEARCH FOR DEVELOPMENT". `fiHiS tti1EANS, OF COURSE, AN
EXERTED EFFORT BY ITS PERSONNEL ~1'O REACH OUT TO THE
'NATURAL RESOURCES OF THE BIG ISLAND IN THEIR RESEARCH'.
FIFTY-FIVE YEARS AGO I PRESENTED TO THE BOARD OF SUPER-
VISORS OF THE COUNTY OF HAWAII THE POSSIBLE FOURTH
INDUSTRY, NAMELY, "TIMBER". I HAVE HAD PERSONAL KNOW-
HOW OF THIS INDUSTRY, FIR5T AS AN ENROLLEE OF THE C.C.C.
(CIVILIAN CONSERVATION CORPS) INITIATED BY THEN, PRESIDENT
FRANKLIN DELANO ROOSEVELT AND PASSED BY CONGRESS FOR THIS
TYPE OF PROGRAM. PLANTING OF THE TREES, SANDALWOOD,
EUCALYPTUS, KOA AND THE FINER KOA WOOD CALLED 'KOU'.
NO INTEREST IN THIS PROPOSAL WAS ACCEPTED. THERE ARE OTHER
TYPES OF NATURAL RESOURCES: BAUXITE, LIMESTONE AND CLAY
AND EVEN TITANIUM (NOT ENOUGH TO MINE) ON DISTRICTS OF THE
ISLAND. (3) ENVIRONMENTAL PROJECTS AND PROGRAMS TO PROTECT
THE WILDLIFE AND VEGETATION OF THE BIG ISLAND. (4) A VERY
NEEDED PROGRAM 47HICH CAN BE INCLUDED T,r~T 'THE PARKS ,'1ND
RECREATION IS "WHOLESOME RECREATIONALACTIV"I'IZE'S'~ FOI2"OU$. YOUT"H, (5)
RESTORATION OF OUR HISTORICAL AREAS AND SIGH`T'S THROUGI30Ui'
THE ISLAND, e.g. "THE KING'S TRAIL", THE PETROGLYPI~S,
HEIAUS (TEMPLE OF THE GODS BY THE KINGS OF HAWAII) AND
CEASE DESECRATING THE TWO BEAUTIFUL MOUNTAINS, NAMELY,
MAUNA KEA (WHITE MOUNTAIN), AND MAUNA LOA (LONG MOUNTAIN).
SINCE WE ARE VRY MUCH CONCERED ABOUT INCREASING THF~ VISITORS'
CONTRIBUTION TO OUR ECONOMY IN ALL DISTRICT LEVELS, AND
THE FACT THAT WE E?Q NOT HAVE AN ACCEPTABLE BEACH OR BEACHES
HERE ON THE EAST SIDE OF THE ISLAND, NAMELY, HILO, I WILL
SEND TO THIS GOVERNING BODY AND ADMINISTRATION A RE~,DESIGN
OF BANYAN DRIVE AND REEDS BAY TO BE MORE SAFE AND ATTRACTIVE
AREAS FOR VISITORS AND THE GENERAL PUBLIC WHO CONGREGATE IN
THIS AREA AND OCCUPYING THE HOTELS. FROM THE DRIVE; STARTING
FROM HILO HAWAIIAN HOTEL AND SURROUNDING HOTELS CONTINUING
THROUGH PARKING AREA ADJACENT TO THE GOLF COURSE AND THROUGH
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BANYAN DRIVE past HILO BAY HOTEL and towards the NEW NANILOA HOTEL, the
Banyan trees overhead are encroaching and entwining, preventing the SUNLIGH"t to "peer"
through to the street, making it very opaque and a very dangerous and unsecured commuting by
the employees of the business enterprises who ordinarily would have to walk across to the
Parking Lot across the Street towards the "Golf Course." The OUTDOOR CIRCLE
ORGANIZATION have been very ADAMANT in having the center of the Trees cut, as they
have stated, "IT WILL DEFACE THE BEAUTY OF THE DRIVE''. No, they are w7ong as the
Trees would still be there, but the Drive would be "safe to drive through or walk across".
3. PROTECTION OF THE CITY OF HILO BY TSUNAMIS AND TIDAL WAVES IN
THE FUTURE. Sometime in the latter part of the 40's and 50's, the U>S. ARMS' CORPS OF
ENGINEERS introduced "A RECEDING WALL FROM THE OLD LIGHTHOUSE IN
DOWNTOWN HILO `WHERE WAIANUENUE EXISTS TO ROUTE 19, THEN ON TO
MOOHEAU PARK." Somehow there were no "LISTENERS". A note of interest is that one of
the Organizations who objected to this PROJECT remarked :"IT IS STUPID, AS WE CAN NO
LONGER BE ABLE TO SEE THE BAY AND OCEAN". Well, I disagreed with them and
stated: While beauty is relative, my main contribution is to HUMAN LIVES, Well, this can be
put to realistic approach by having our CONGRESSIONAL REPRESENTATIVES FROM
HAWAII seek FEDERAL GRANTS for this most important Project.
4, ELIMINATION OF POLLUTION IN THE BAY AND HARBOR.
There must be a concerned and exerted effort by the COUNTY, STATE AhTD FEDERAL
OFFICIALS in this type of Endeavor. I would suggest after, having a conversation with my son,
DR. FRANCIS L. BENEVIDES, with an ELECTRONIC ENGINEER DEGREE,to segmentized
the existing BREAKWATER in interval areas to allow the "flow in and flow out" system of
waves, and even be `helpful' in minimizing the strength of a TIDAL WAVE and TSUNAMI
wave action.
5. BREAKWATER PROTRUDNG FROM the "OLD HILO SUGAR MILL". This would
allow apassage-way through the channel and also prevent the "SPLASH of Tidal tivave of
Tsunami endangering HILO. In the past, experiencing, personally on the onslaught of this
destruction was caused by a wave action hitting the coastline of the entrance to the Hilo Bay and
City of Hilo by splashing against the sides of this coastline.
6. REDESIGN REEDS BAY FOR A MORE ATTRACTIVE AND YET "GATHERII~'G
PLACE" for our commuters. I have redesigned a sketch of a `new Reeds Bay' that: allow more
Beach area, parking and security.
AN ADDED NOTE IN THE PROTECTION OF OUR HARBOR, I AM ALSO
INTRODUCING THE ARRIVAL OF MORE OCEANLINERS TO HILO (we did it in the 20's
and 30's}, we can do it again. With the arrival of Oceanliners, the one `selling point' is the
presenting of Flower leis (i~TOt artificial) to the visitors as we did in the past "WHEN WE HAD
DIRECT FLIGHTS TO HILO" until the year 1981when some of our LEADERS for
"INVESTMENT GREED" `crucified Hilo and East Hawaii in its economic grow-th.' And yet,
the Audacity to place a stupid sign "INTERNATIONAL AIRPORT". What International
Airport?? Do you see a great number of Aircraft (International) to HILO? SUGGESTION: The
sign is a misnomer and should be TAKEN DOWN AND REPLACED WITH A NE~V SIGN
where visibility or identifying the entrance of the Airport NORTH and SOUTH on
KANOELEHUA AVENUE. Asit is now, there is no sign stating the entrance to the AIRPORT
on KANOELEHUA AVENUE facing North. In its place, the name as was always in the past,
GENERAL LYMAN AIRFIELD or AIRPORT. In the present identification, are we making a
mockery of HILO ? Whomever were responsible for the name, "II~'TERNATIONAL AIRPORT"
had no sense of reasoning. Let's do something realistic for the city of Hilo, and not destroy it.
THINK ABOUT IT.
IN the area of presenting of leis to the visitors, as aforementioned, we m~.>st seek more
allocated funding from the HAWAII VISITORS BUREAU for this type of venture.
TO THE PEOPLE OF HILO: WAKE UP AND BE HEARD FOR THE FUTURE
OF OUR CHILDREN, THOSE WHO ARE HERE NOW, "SAVE THE CHILDREN,
SAVE THE ELDERS", AND ABOVE ALL SAVE THE CITY OF HILO.
FRANCIS L BENEVIDES SR
PO BOX 1877
HIlO, HI 96721-1877
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w:-~--..... F'O Sox 631
~ Vicksburg, Mississippi 39180
T0: FRANCIS L. BENEVIDES, SR.
- - MEMBER-ASSIGNED
! 1940 TO 1946
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the shoreline adjustment behind a segmented breakwater that is permeable and
overtopped.
d. Segmented Breakwaters. A segmented breakwater offers a very func-
tional solution for a long section of shoreline that requires wave transmis-
sion to prevent tombolo formation. The structure can be built nearshore in an
economical water depth because it permits a constant proportion of wave energy
into the protected area. Also, the diffracted waves have the same period as
the incident waves. Segmented breakwaters can be designed to allow the beach
in their lee to accrete enough sediment to provide an erodible buffer during
storms and still maintain the natural longshore transport rate during normal
wave conditions.
The amount of energy reaching the lee of the structure is controlled by
the width of the gaps between the breakwaters and the wave diffraction through
these gaps. The gaps should be at least two wavelengths wide, and the length
of each structure segment should be less than the distance offshore. Provid- '
ing fewer gaps of greater width will cause the shoreline to respond with
spaced bulges and embayments with an enlarged relief (the seaward distance
from the more shoreward point of the embayment to the tip of the cuspate
spit), which does not provide uniform storm protection along the project.
If this is not acceptable, increasing the number of gaps and shortening the
length of each segment will promote features of less relief, providing more
uniform protection. Segmented offshore breakwaters are illustrated in. Figures
5-30, 5-32, and 5-33. Figure 5-33 illustrates the use of offshore breakwaters
in conjunction with a beach fill.
e. Positioning with Respect' to Breaker Zone. Placing the breakwater
landward of the normal breaker zone will advance the shoreline and may cause
tombolo formation (see Fig. 5-32). If positioned well shoreward of the
breaker zone, a large percentage of the total longshore transport will pass
seaward of-the structure and the effect on the adjacent shoreline will be less
severe. This method fs not recommended for coasts with steep beach slopes and
narrow surf zones because the area shoreward of the breakwater will tend to
fill completely, turning the breakwater into a seawall.
f. Structure orientation. The orientation of the breakwater with. respect
to both the predominant wave direction and the original shoreline can have a
marked effect on the size and shape of the resulting cuspate spit or tombolo.
A change in structure orientation modifies the diffraction pattern. at the
shoreline, and subsequently, the shore response. An approximation of the
shape of the shore response when waves are normally incident to the shoreline
can be determined by using the procedures discussed in Chapter 2, Section IV
to determine the diffracted wave crest configuration. For waves that are
extremely oblique to the shoreline, it is recommended that the breakwater be
oriented parallel to the incoming wave crests. fihis will provide protection
to a longer section of shoreline for a given structure length; however, it
will probably increase the amount of construction material required for the
structure since one end of the breakwater will be in water deeper than if it
were oriented parallel to the bottom contours.
6. Other Considerations.
Apart from shore response, there are several other factors which affect
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` Coastal Engineering Research Center
_~::......4 C~EPAR`fMEN~` OF `THE ARMY
Waterways Experiment Station, Corps of Engineers
~w~ - _ PO Rox 631
Vicksburg, Mississippi 38180
- •
- TO FRANCIS L. BENEVIDES, SR.
- ASSIGNED-MEMBER FROri
- ~ 19 4 0 TO 19 4 6
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I ~~sF Washington, DC 20314
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d. Concrete-Caisson Breakwaters.' Breakwaters. of this type are built of
reinforced concrete shells that are floated into position, settled on a
prepared foundation, filled with stone or sand for stability, and then capped
Frith concrete or stones. These structures may be constructed with or without
parapet walls for protection against wave overtopping. In general, concrete
caissons have a reinforced concrete bottom, although open-bottom concrete
caissons have been used. The open-bottom type is closed with a temporary
wooden bottom that is removed after the caisson is placed on the foundation.
`the stone used to fill the compartments combines with the foundation material
to provide additional resistance against horizontal movement.
Caissons are generally suitable for depths from about 3 to 10 meters (10
s.o 35 feet). The foundation, which usually consists of a mat or mound of rub-
ble stone, must support the structure and withstand scour (see Ch. 7,~ Sec.
III,8). Where foundation conditions dictate, piles may be used to support the
structure. Heavy riprap is usually placed along the base of the caissons to
arotect against scour, horizontal displacement, or weaving when the caisson is
supported on piles.
IX. BREAKWATERS, OFFSHORE
Offshore breakwaters are usually shore-parallel structures located in
cater depths between 1.5 and 8 meters (5 and 25 feet). The main functions of
breakwaters are to provide harbor protection, act as a littoral barrier, pro-
aide shore protection, or provide a combination of the above features. Design
considerations and the effects that offshore breakwaters have on the shoreline
and on littoral processes are discussed in Chapter 5, Section ZX.
T~S•
Offshore breakwaters can usually be classified into one of two types:
~e rubble-mound breakwater and the cellular-steel sheet-pile breakwater. The
most widely used type of offshore breakwater is of rubble-mound construction;
^.owever, in some parts of the world breakwaters have been constructed with
~imber, concrete caissons, and even sunken ships.
A variation of offshore breakwater is the floating breakwater. These
structures are designed mainly to protect small-craft harbors iri relatively
sheltered waters; they are not recommended for application on the: open coast
recause they have little energy-dissipating effect on the longer period ocean
Wives. The most recent summary of the literature dealing with floating break-
~-atera is given by Hales (1981). Some aspects of floating breakwater design
are given by Western Canada Hydraulics Laboratories Ltd. (1981).
Selection of the type of offshore breakwater for a given location first
depends on functional needs and then on the material and construction costs.
determining factors are the depth of water,. the wave action, and the avail -
~.bility of material. For open ocean exposure, rubble-mound structures are
s~sually required; for less severe exposure, as in the Great Lakes, the
cellular-steel sheet-pile structure may be a more economical choice. Figure
x--56 illustrates the use of a rubble-mound offshore breakwater to trap
l:Ltoral material, to protect a floating dredge, and to protect the harbor
~~trance.
Probably the most notable offshore breakwater complex in the 1lnited
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States is the 13.7-kilometer-long (8.5-mile) Los Angeles-Long Beach breakwater
complex built between 1899 and 1949. Other U.S. offshore breakwaters are
listed in Table 5-3 of Chapter 5.
2. Segmented Offshore Breakwaters.
Depending on the desired function of an offshore breakwater, it is often
advantageous to design the structure as a series of short, segmented break-
waters rather than as a singular, continuous breakwater. Segmented offshore
breakwaters can be used to protect a longer section of shoreline, while a:Llow-
ing wave energy to be transmitted through the breakwater gaps. This permits
a constant proportion of wave energy to enter the protected region to retard
tombolo formation, to aid in continued longshore sediment transport at a
desired rate, and to assist in maintaining the environmental quality of'. the
sheltered water. Additionally, the segmented breakwaters can be built at a
reasonable and economical water depth while- providing storm protection for the
shoreline.
Figure 6-66 illustrates the structural details of the segmented rubble-
mound breakwater at Lakeview Park, Lorain, Ohio, which is on Lake Erie. This
project, which was completed in October 1977, consists of three detached
rubble-mound breakwaters, each 76 meters long and located in a water depth of
-2.5 me-tars (-8 feet) low water datum (LWD). The breakwaters are spaced 50
rseters (160 feet) apart and are placed about 145 meters (475 feet) offshore.
`lfiey protect 460 meters of shoreline. The longer groin located therf: was ,
extended to 106 meters (350 feet), and an initial beach fill of 84,100 cubic
teeters (110,000 cubic yards) was placed. A primary consideration in the
design was to avoid the formation of tombolos that would interrupt the
~ongshore sediment transport and ultimately starve the adjacent beaches.
Immediately after construction, the project was monitored for 2 years.
_*indings indicated that the eastern and central breakwaters had trapped
littoral material, while the western breakwater had Lost material (Walker,
ark, and Pope, 1980). The net project gain was 3800 cubic meters (5,000
~bic yards) of material. Despite exposure to several severe storms from the
.ast during periods of high lake levels, there had been na damage to the
reakwaters or groins and no significant erosion had occurred on the lake j
~ttom between the breakwaters. I{
X. CONSTRUCTION MATERIALS AND DESIGN PRACTICES i
The selection of materials in the structural design of shore protective
corks depends on the economics and the environmental conditions of the shore .
a.ea. The criteria that should be applied to commonly used materials are I
i~scussed below.
Concrete.
i
The proper quality concrete is required for satisfactory performance and ~
r~Tability in a marine environment (see Mather, 1957) and is obtainable with
t=:3 concrete design and construction practices. The concrete should have low
a~~eability, provided by the water-cement ratio recommended for the exposure '
:==.3itions; adequate strength; air entrainment, which is a necessity in a
6-95