WCI Cable contracted with Alcatel Submarine Networks to build
and install their Alaska Northstar Network. The Nedonna segment
of the NorthStar cable was constructed at the Alcatel manufacturing
plant in Portland, Oregon. Cable was loaded on the Cable Ship
Maersk Fighter at Alcatel’s dock. The vessel set sail from
Portland on the morning of April 22, 1999. A pre-lay grapple
run was conducted to assure the route was clear. Cable installation
operations began on the morning of April 23rd, when a scuba
diver swam a line from the ship through the surf. This was
used to pull a heavier line, which was later connected to
a bulldozer near the beach manhole. The bulldozer pulled the
armored fiber-optic cable from the ship to shore. Buoys suspended
the cable across the surface to avoid seabed contact.
Cable Burial
Cable laying and burial commenced on April 25 at 0800 hours
in 7 fathoms of water with a submersible underwater plow.
This is about .7 nm (nautical mile) offshore of the beach
manhole. Initial plow burial averaged about .9 meter (2.9
ft). The F/V Abiqua, home ported in Garibaldi, was utilized
to ferry personnel to and from Garibaldi, to act as a fishery
patrol vessel and to remove a few crab pots that were in the
cable route. These pots were replaced after the cable vessel
and plow passed by. Only one "stuck" crab pot was unable to
be moved, and the affected fisherman was paid for the loss
of this trap.
The plowing was much more difficult in the area beginning
around 45° 39.8’ N x 124°19.5’ W in 83.5 fathoms, a fishing
area commonly referred to as "the reef." The difficult plowing
resulted in equipment breakdowns and slow progress. Cable
burial in this area averaged .54 meter (21 inches). The shallowest
reading recorded in this area showed just over 10 inches of
burial.
Once the plow was through the hard bottom at about 45°40.1’N
x 124°25.6’ W, plowing became much easier and the corresponding
burial depth increased. From this point to the end of plow
burial, burial depth averaged 1.03 meters. Plow burial ended
at 45°41.9’ N x 124°50.1’ W due to the inability of the plow
to operate on the 11° steep slope. From this point westward,
the Maersk Fighter surface laid the cable to a temporary termination
point about 60 nautical miles (nm) offshore. This cable end
was later picked up by the cable ship Fu-Lai, which spliced
its cable to the segment left by the Maersk Fighter. The Fu-Lai
laid its load of cable in deep sea on to Alaska. The Kigoria,
from Victoria, BC, utilized a Phoenix III ROV (remote
operated vehicle) to water-jet bury the cable from the end
of plow burial to 45°41.4’ N x 124°56.1’ W. This was approximately
41.9 nm west of Nehalem Beach in 822 fathoms (1503 meters)
of water. Repeated passes were necessary to achieve the one-meter
depth. The Kigoria also used the ROV to verify the burial
of an optical repeater, and other post lay inspection of the
cable.
Cable Patrol
Two other vessels, the F/V Olympic out of Newport and the
F/V Prospector from Astoria, served as fishery patrol vessels,
broadcasting warnings to mariners, and providing other logistical
support services. These patrols continued until the cable
was completely buried in the fishing grounds. Little fishing
activity occurred in the area during the cable installation,
and no conflicts occurred. One humpback whale was observed
in the vicinity during post-lay burial.
Inshore / Surf Zone
The Oregon Fishermen’s Undersea Cable Committee did not have
an observer aboard the vessel contracted to bury the cable
in the inshore/surf zone out to 11 fathoms. The installers
hired a Norwegian firm, SEA TRENCH TECHNOLOGY, AS, to bury
the cable. A workboat/barge was used to support a submerged
trencher, which utilized waterjets to fluidize the seabed
and allow gravity to sink the cable into the seafloor. The
trencher was equipped with a guide roller secured on the armored
cable to keep it on the cable path. The reaction force of
the waterjets, which were driven by a 250-hp. diesel engine
on the workboat, propelled the trencher forward. A six-inch
waterhose delivered high-pressure water from the workboat
to the trencher. Three scuba divers assisted in the operations,
which were conducted May 10 to May 16, 1999. The distance
trenched by this method was approximately 1250 meters, beginning
at the point where the Maersk Fighter began its plowing. The
Sea Trench Technology, AS, trencher Sea Trench T-5 buried
the cable shoreward to the beach at a depth of one meter or
more. Trenching on the beach was accomplished by a team of
seven track excavators at the time the cable was landed. Beach
burial met or exceeded the specifications set forth by the
State of Oregon and all permitting agencies.
Beach to the Cable Landing Station
In concert with the local and state statutes and agency approvals,
WCI Cable has placed 8 five-inch steel conductors from the
three dual marine cable beach manholes on Lake Street approximately
600 feet to the west through the protective dune at Nedonna
Beach. A temporary pull box constructed with treated timber
houses these steel conductors, of which one is currently utilized
by Northstar/WCI Cable for the Alaska-to-Nedonna Beach marine
network. Because of the construction between the high water
mark at the temporary pull box and the beach manholes, only
the submerged beach will have to be disturbed to install one
to five additional cables at this location. Northstar/WCI
Cable engineered and installed three concrete beach manholes
on Lake Street east of the protective dune into which all
marine cables landed will anchor. From the beach manholes
to the cable station, (approximately 950 feet) Northstar/WCI
Cable has installed 8 four-inch PVC ducts including two with
three 1-1/4" innerducts. This duct bank is buried under the
paved road and is protected with a 36" lift of red CDF material.
As an accommodation to the neighborhood, Northstar/WCI Cable
has re-paved all of Lake Street including a previously graveled
portion. No more environmental disturbance is required to
land up to six marine cables through this duct system.
From the turning box located on the Port of Tillamook Bay
right of way and under the highway, Northstar/WCI Cable has
installed 11 five-inch steel conduits to their property east
of Hwy 101, thence to two 15'x9'x4' cable vaults adjacent
to the north wall of the cable station. Northstar/WCI Cable's
property west of the cable station and east of Highway 101
has been landscaped and wetlands have been enhanced to add
to the beautification and environmental elegance of the area.
The enhancement includes additional stream reclamation.
The security system at the cable station has been designed
and installed to work in harmony with the environmental setting
of the wetlands surrounding the Northstar/WCI Cable landing
station.
Back Filling Cable Trench
Conclusion
This experience identifies the critical need and importance
of involving fishermen in the earliest stages of submarine
cable route planning. Because fishermen have extensive knowledge
of the seafloor in which these cables will eventually be installed,
it is essential that cable owners, installers, and contractors
consult with the fishing industry early in the route selection
process. This type of valuable exchange will not only assist
these stakeholders, but provide cost saving intelligence to
the entire process. Oregon fishermen and fisherman all over
the world will benefit from these types of cooperative relationships.
The Oregon Fishermen’s Undersea Cable Committee believes
that all who were involved did an exemplary job given the
hard seabed conditions on the selected route. The installation
was successful due to the diligent efforts of the cable owner,
installation contractor and all subcontractors.
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