View
Graphic: Progress
Map (3/21/05)
View
Graphic: Inner
Harbor Schematic
"Before
and After" Photos of Ft. Macon
(see
picture title for dates of photos)
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Construction
Notes:
3/21/05 (Final
Update) - Marinex Construction completed inner harbor
dredging maintenance activities with concurrent beach placement last
week and has begun the demobilization process. A graphic depiction
of the beach nourishment ranges completed this year (inner harbor
and Brandt Island) are provided in the progress
map above. Also, Manson Construction
completed all activities associated
with outer harbor maintenance last week as well (offshore disposal)
and have since mobilized to the Wilmington Harbor for maintenance
dredging
at
this
Navigation
Project.
3/14/05 -
Both maintenance dredging scopes of work in the inner harbor
with concurrent beach placement (Marinex Construction), and the
outer harbor with offshore disposal (Manson Construction) could
be completed within the next
week. Dike
reconstruction
along the outer rim of Brandt Island should be initiated sometime
next week.
3/7/05 -
Maintenance dredging of the inner harbor with concurrent beach placement
continues
(see progress map for beach nourishment placement area). Maintenance
dredging activities are currently centered within the turning basin
(see
inner harbor schematic above).
2/28/05 – Maintenance
dredging of the inner harbor with concurrent beach placement continues
(see progress map
for beach nourishment placement area). Dredging activities are currently
located near the Beaufort Bridge and will be subsequently positioned
within the turning basin (see inner harbor schematic above). Over 300,000
cubic yards have been dredged to date from the inner harbor and work
should be completed within the next 3-4 weeks.
Also, Manson Construction initiated
outer harbor dredging maintenance work with offshore disposal on 2/24/05
utilizing the Bayport, a 5,500 cubic yard capacity hopper dredge. Maintenance
activities should take 10-14 days to complete (~300,000 cubic yards
total). Manson has a single contract to complete both Morehead City
and Wilmington Harbor scopes of work.
Dike reconstruction along the rim of Brandt Island
should begin in a couple of weeks, utilizing an subcontractor contracted
by Bean Stuyvesant.
2/21/05 – Maintenance
dredging of the inner harbor with concurrent beach placement continues
(see progress map for beach nourishment placement area). Dredging
activities are currently centered within the turning basin (see
inner harbor schematic above).
2/14/05 – Marinex
Construction’s 18” cutterhead-suction dredge, Hampton
Roads, completed the infilling of the pre-existing gap located
near the Ft. Macon bathhouse, where sediments pumped from Brandt
Island and the Inner Harbor merged. Maintenance dredging of the Inner
Harbor
continues and the sediments are currently being placed along the
eastern half of the Ft. Macon State Park oceanfront (see progress
map above). The Hampton Roads encountered a minor mechanical
problem last week but maintenance dredging activities
are are currently centered along the eastern flank
of the turning
basin (see inner harbor schematic above). It is estimated that maintenance
dredging will take a month to conclude. Also, demobilization of
land-based pipeline
associated with the Brandt Island Pump-Out is progressing nicely.
2/7/05 – Bean Stuyvesant’s 30” cutterhead-suction
dredge, the Meridian, departed the Morehead City Harbor
last Monday (1/31/05) subsequent to completing the pump-out of Brandt
Island the
week prior. The Hampton Roads, Marinex Construction’s 18” cutterhead-suction
dredge, is continuing bi-annual (every other year) maintenance dredging
of the Inner Harbor and is currently positioned in Range C near the
Jet Fuel Storage Tanks located on Radio Island (see Inner Harbor schematic
above). The shoal material encountered during maintenance of the Inner
Harbor is transferred via submerged/buoyed/land pipeline to the shorelines
of Fort Macon. The discharge is currently located near the 4-WD Ramp
at the Ft. Macon bathhouse (~Station 9.5) and is dovetailing with the
beachfill that emanated from the Brandt Island Pump-Out. The sediment
grain size as of late has been finer than in previous weeks causing
the fill to diffuse at gentler slope.
1/28/05 – Bean
Stuyvesant completed the Brandt Island Pump-Out this past Tuesday
morning (1/25/05) at approximately
4:00, and should begin dike reconstruction within the next several
days. Approximately 2.8 million cubic yards were removed from the
island and placed along the shorelines of Atlantic Beach and Ft.
Macon in
less than three months time. The last stages of beachfill activities
progressed eastward from Commerce Way in Atlantic Beach and concluded
at Station 9.6 in Ft. Macon (approximate).
Meanwhile,
Marinex Construction is continuing maintenance dredging activities
within
the inner harbor with concurrent beach nourishment
along Ft. Macon. The current discharge area is located at Station 8.6,
at the Ft. Macon Bathhouse groyne – see pictures below and progress
map above. The cutterhead-suction dredge, Hampton Roads has completed
maintenance dredging of Bulkhead Channel and Range B near the cutoff
and its intersection with Bulkhead Channel (see harbor schematic above).
The Hampton Roads is currently dredging near the intersection of Ranges
B and C. Sediment quality remains excellent (grain-size and aesthetics),
and in all likelihood Marinex will close the nourishment gap near the
Ft. Macon Bathhouse, dissemble pipe, and “thicken” the
nourishment template within Ft. Macon; again working east to west.
1/24/05 – Bean Stuyvesant’s 30” cutterhead-suction
dredge, the Meridian, could complete the Brandt Island pump-out tomorrow
(~2.8 million cubic yards total) with the sediment discharge emanating
from the latter stage of this effort located at ~Station 9.6, just
east of the Atlantic Beach/Ft. Macon State Park boundary. Final surveys
and dike reconstruction within Brandt Island could begin later this
week.
Also, Marinex Construction’s 18” cutterhead-suction
dredge, the Hampton Roads, is currently situated in the northern
half of Bulkhead
Channel (see inner harbor schematic above). As mentioned in previous
updates, the shoal material encountered during maintenance dredging
is transferred via a buoy/land pipeline run to Ft. Macon with the discharge
initiating at Station 4.725 and progressing west. The discharge is
currently positioned at Station 8.2 (see progress map above), which
is located near the Ft. Macon swimming beach/groyne. Marinex could
complete Bulkhead Channel later this week and continue dredging Range
B prior to entering the Turning Basin.
Sediment quality has been good for the past week regarding aesthetics
and grain-size from both Brandt Island and the Inner Harbor areas.
1/17/05 – The Hampton Roads (Marinex Construction) has recently entered
Bulkhead Channel and progressing northward from its intersection
with Range B in the Inner Harbor (see inner harbor schematic above).
The shoal material encountered during maintenance dredging is transferred
via a buoy/land pipeline run to Ft. Macon with the discharge initiating
at Station 4.725 and progressing west. The discharge is currently
positioned at Station 6.7 (see progress map above). The Hampton
Roads is undergoing minor repairs that emanated from a mechanical
breakdown that occurred this past weekend. The repairs should be
completed today.
The Meridian (Bean
Stuyvesant) was under repair for a majority of the past two weeks
and re-initiated the pump-out of Brandt Island this past
Saturday (1/15/05). The discharge is located at Station 12.1 in Atlantic
Beach near Commerce Way and will progress east to link with the Hampton
Roads beach nourishment effort.
1/9/05 - (A) Marinex
Construction’s 18” cutterhead suction
dredge, the Hampton Roads, initiated inner harbor maintenance
dredging with concurrent beach nourishment Friday evening (1/7/05).
The Hampton
Roads is currently located within Range B, near its connection
with the Cutoff (see Inner Harbor graphic above). The beach nourishment
reach
will begin over 1,500 feet west of the terminal jetty at Ft. Macon
(Sta. 4.725 on the progress map above) and progress westward towards
the Ft. Macon Bath House. The sediment quality is excellent in terms
of grain size and aesthetic appearance (see photos below).
(B) Bean
Stuyvesant’s 30” cutterhead
suction dredge, the Meridian, that has been dredging Brandt Island
for the past two months has been down
a majority of the past week for repairs. The discharge will now be
diverted to the east from Commerce Way in Atlantic Beach to meet with
the fill progressing westward from the Hampton Roads dredge pipe extension.
The westernmost point of the Brandt Island fill reached Sta. 28.6 (the
western edge of Ocean Ridge), and there is a degree of uncertainty
if any of the sand remaining in Brandt Island (600,000 cubic yards
estimated volume) will be placed any further west than Sta. 28.6 (see
progress map above).
1/3/05– Marinex
Construction’s 18" cutterhead suction dredge, Hampton
Roads,
arrived to the Morehead City Harbor this past week to begin inner
harbor channel maintenance dredging with concurrent beach nourishment
extending from the Fort Macon jetty (Station 4.7) to Commerce Way
in Atlantic Beach (Station 12.1). Although the schedule
is tentative at this point, Marinex will likely dredge the Bulkhead
Channel
portion of the inner harbor before advancing to the inner harbor
proper and the turning basin (see inner harbor map above). The
Meridian, positioned in Brandt Island, is continuing to “pump-out” the
material located in this upland disposal facility with the discharge
point currently located at Station 27.9 (see progress map above).
The material placed on the beach in the past dew days has been
finer-grained
than in
weeks
prior. This has hampered progress along the beach but there are
no mud balls to report.
12/27/04 – Productivity
has remained steady throughout the Christmas season with the discharge
pipe currently positioned at Station 26.8, located in the heart of
the Ocean Ridge subdivision (see progress map). It’s anticipated
that the fill pumped from Brandt Island will reach the project’s
end target, which is situated at Station 33.8 or ~500 east of the
Sheraton Pier. In terms of distance, approximately 47% of the project
has been completed to date. The remaining section extending from
Ocean Ridge to the Sheraton Pier will be completed utilizing Brandt
Island material, and the remaining reach extending from the Fort
Macon terminal jetty to Commerce Way in Atlantic Beach will be
completed utilizing inner harbor dredged material via a cutterhead-suction
dredge (Marinex Construction).
12/17/04 – The Meridian has been operating all week and progress/productivity
has been solid, averaging a few to several hundred linear feet per
day. Correspondingly, sediment quality has also remained good with
the current discharge point located at Station 24.2 with the
next
Y-valve positioned at Station 25.5, which has also been utilized
during the addition of pipe on the active pipe reach stemming from
Station
20.5 (see progress map).
12/12/04 – Productivity
has been “good” in the past several days since the
berm width has been narrowed for the Project coupled with the
fact that the Meridian has been encountering coarser-grained
material in Brandt Island that is also relatively free of mudballs
and aesthetically more
pleasing. The discharge area is currently located at Station
22.8 (see progress map), located just west of the Atlantic Beach
Circle.
Marinex Construction is now scheduled to begin inner harbor maintenance
dredging/beach nourishment in early January.
12/7/04 -
As discussed in the previous updates, there appears to be just enough
clay and fine-grained sediments in Brandt Island to cause
the slurry to run down the beach without “dropping” the
coarse-grained material along the construction template. The
fine-grained material is more or less diffusing offshore and
therefore the offshore
slope of the fill is running at 1:50 to 1:60 (vertical :horizontal)
for instance, rather than 1:20 or 1:25. This creates an excessively
gentle offshore slope that requires an equally tremendous amount
of material to achieve (see
schematic). Thus, what was thought
to only take ~70 cubic yards per linear feet (cy/ft) to complete
is now consuming ~200 cy/ft to complete. Beach nourishment activities
should have progressed westward well beyond the Circle in Atlantic
Beach with the volume of sand dredged out of Brandt Island, but
the distance filled to date is ~4,600 linear feet with well over
1,000,000 cubic yards pumped out of Brandt Island.
At
this rate, we will simply not have enough material to construct the
Section
933 Option for Pine Knoll Shores. Based on these set of
circumstances, the Section 933 Project this year will not occur (see Corps’ press
release). A stop work order has been issued to Bean
Stuyvesant for the Section 933 Project. The berm width will also be
reduced for the remainder of the project to maximize pumping distance
with the hopes of reaching the westward end of Atlantic Beach.
While
there are some mudballs along the beach along the corridor extending
from Triple S to Oceanna piers (higher concentrations in
some areas than others), they are resting on fine-grained sand or coarse-grained
silt (i.e., fine-grained material). If the fill was all mud (silt and
clay only), the material wouldn't settle along the beach and rather
disperse into the Ocean. The dredging contractor would have pumped
over a million cubic yards out of Brandt Island with no beachfill along
the shoreline. That's not the case - the beach is extremely wide in
between Triple S and Oceanna piers (see aerial
photograph 11/30/04).
On
a positive note, the sand pumped this past weekend just west of Sportsman's
Pier was essentially free of clay with a more brown/tan
hue to the slurry, and is more aesthetically pleasing. However, the
slurry remains fine-grained and the slope problem still remains an
issue and would plague our efforts if the fill was scheduled to be
pumped into Pine Knoll Shores.
Also,
Marinex Construction is scheduled to arrive at the Inner Harbor to
begin maintenance work
with beach placement on December 15th – 18th.
The fill is planned to cover the area extending from the terminal jetty
at Fort Macon westward to Commerce Way in Atlantic Beach.
11/28/04 – The Meridian has
pumped continuously during the past week. The fine-grained material
remains an issue by
causing the slurry to cascade down the beach without “dropping” the
coarser-grained material. This requires more sand to be utilized
to complete the berm template designed for the project. The situation
is being monitored closely.
11/22/04 – The
relatively minor amounts of mud in Brandt Island, when mixed with
sand and water, is essentially lowering the slurry’s
ability to drop the coarser-grained material on the beach when pumped.
The slurry is cascading down the beach without depositing the volume
of sand expected and therefore has dampened the project’s progress
along the beach. The pump-out is in the infantile stages
however, and hopefully beach construction productivity will improve.
11/15/04 – After
a few days of pumping, the Meridian encountered a couple of mechanical
problems and did not operate through a majority of the past weekend.
Dredging/pumping could resume sometime this evening. Approximately
1,300 linear feet of the beach has been constructed (see progress
map).
11/10/04 – Bean
Stuyvesant’s
cutterhead-suction dredge, the Meridian, encountered a mechanical
problem with the anchoring mechanism
just hours after initiating the Brandt Island Pump-Out this past Sunday.
The apparatus underwent repair,
and pumping resumed today.
11/7/04 – Bean
Stuyvesant’s cutterhead-suction dredge, the Meridian,
began to cut through the dike wall leading into Brandt Island earlier
this
morning once the land-based pipeline along Commerce Way was completed.
Bean is flushing the dredge pipes and working through any pipeline
problems today. The actual dredging and pumping activity should be
initiated later today, or early tomorrow. The full compliment of
survey stakes and safety netting along the beach should also be installed
later day, or early tomorrow. The beachfill will begin at Station
13.6 (see map above), or just west of Triple S, and progress westward
into the center of Atlantic Beach and into Pine Knoll Shores.
11/1/04 – Bean
Stuyvesant's cutterhead-suction dredge, the Meridian, arrived last
week and is anchored along the eastern flank of the N.C. Port Authority
complex. The submerged pipeline that will transition from the dredge
to the land-based pipeline near the intersection of Commerce Way
and Hwy 58 in Atlantic Beach should arrive to the harbor this week.
Dredging and pumping activities should begin this weekend.
10/20/04 – The
U.S. Army Corps of Engineers formally awarded the Section 933
option to Bean Stuyvesant last week. The
estimated start date is 11/1/04.
HOW
TO INTERPRET THE PROGRESS MAP FOR
PHASE
II OF THE SECTION 933 PROJECT
Phase
II of the Section 933 Project, or the “Pump-Out Phase” will
utilize dredged shoal material from the inner harbor reach of the
Morehead City Harbor Federal Navigation Channel for beach nourishment
in two zones located along Bogue Banks. One zone is referred to the “Base
Plan” and encompasses the shorelines of Fort Macon and Atlantic
Beach (~26,000 feet excluding a 1,000 foot buffer at each pier).
Beach nourishment in this area is a 100% cost to the Federal government.
The second zone is a Federal/non-Federal cost-shared area encompassing
a majority of the Pine Knoll Shores shoreline (~26,000 feet). This
second zone simply constitutes Phase II of the Section 933 Project.
As
mentioned above, the sand utilized for beach nourishment is dredged
shoal material from the inner harbor. “Shoal material” is
a term for sediments that fill the channel and are subsequently required
to be dredged in order to maintain a minimum depth for cargo ships
leaving and entering the Port of Morehead City. The inner harbor
is dredged or “maintained” every other year and the sediments
dredged from the channel are temporarily stored at the upland disposal
facility of Brandt Island, located immediately NW of Fort Macon.
Once Brandt Island becomes “full”, the shoal material
is “pumped-out” to the beaches of Bogue Banks. This usually
occurs on a decadal basis (every ten years). The maintenance material
that is required to be dredged from the inner harbor in winter 2004-05
will be pumped directly to the beach rather than stored in Brandt
Island.
The
dredging contract has been awarded to Bean
Stuyvesant and the cutterhead-suction dredge, the Meridian will
be used to pump the sand from Brandt Island to the Base Plan and
Section 933 zones of the beach. Marinex has
been subcontracted by Bean Stuyvesant to complete
the inner harbor maintenance work for 2004-05. A cutterhead-suction
dredge utilizes
a crane placed on a barge-type vessel that positions the cutterhead,
which looks like a gigantic drill bit, along the seafloor. The cutterhead
agitates the sandy bottom, and the resulting slurry of sediment and
water is subsequently suctioned into a long tube transitioning into
a pipeline that can be extended to a beach or disposal area.
An
underground sleeve helps connects the pipeline extending from Brandt
Island to the beach. The sleeve runs underneath Hwy 58 and towards
the shore along Commerce Drive in Atlantic Beach. From this point,
the pipeline will run eastward to complete the Fort Macon section
of the project, then westward into Atlantic Beach and the Section
933 zone of Pine Knoll Shores. Booster pumps are required for the
western leg of the pipeline extension because the distance associated
with completing this reach overwhelms the capacity of the pumps located
on the dredge. Without booster pumps, the transferal of sand from
Brandt Island to the beach would become a slow and inefficient process.
Once the slurry of sand and water begins reaching the shore, the
material is bulldozed into general construction specifications for
subsequent grading into final contours, tilled, and opened for recreational
use.
Project
engineers use “stations” positioned along the beach to
track nourishment projects and to verify in-place volumes of sand
placed on the beach by dredging contractors. The stations for the
Brandt Island Pump-Out/Section 933 Project are provided in intervals
of five in the figure above. These station numbers and the tick marks
in between conveniently correspond to linear feet along the beach.
For instance, the distance between station “40” and “45” on
the figure above is approximately 5,000 feet. The distance from station “25” to
tick mark “24”, located immediately east, is approximately
1,000 feet. If you visit the beaches of eastern Bogue Banks this
winter you may see wood or metal stakes at the base of the dunes
that will identify these station numbers that will enable all of
us to keep track of the construction progress.
The “area
of detail” figure provides a detailed view of the Base Plan
and Section 933 zones to be completed in the winter of 2004-05 with
station numbers and the general location of the land-based discharge
pipeline. The shaded areas in red represent the completed portions
of the project and will be updated on a weekly basis throughout the
construction.
