Project Tag: Pacific Northwest

Remote Wreck Site Presents Logistical Challenges

In early October 2016, the US Coast Guard (USCG) responded to a distress call from the crew of the 45-foot sailing vessel Soteria, who reported their vessel was taking on water during a storm. At the time, the Soteria was located 40 miles northwest of Gray’s Harbor off the Washington Coast; weather reports indicated 20-foot …

Seattle T-46 Barge Refloat & Fender Piling Repair Project

Seattle’s most extensive current civil works project,the Alaskan Way Viaduct replacement tunnel,is being constructed using the world’s largest tunnel boring machine ‘Bertha’. Due to the proximity of the construction site to the waterfront,the dirt and rock spoils from this effort are transported via conveyor belt to Pier 46. From there it is loaded onto barges for further transport.

Progress was recently halted due to an incident involving a spoils barge and a badly damaged pier.

In the early morning hours,the barge being utilized began to list and then capsize. Tunneling operations were halted due to the partially capsized barge at the adjacent pier and an impending rising tide.

The tunnel project personnel called Global’s 24 hour number to request immediate assistance. Global dispatched a Salvage Master who was on scene within 30 minutes of the call.

Following the removal of the unstable barge from underneath the pier,Global commenced a full salvage assessment. This included analysis of the barge’s stability and an underwater survey. The spoils had shifted on the barge causing it to list heavily to one side. Global developed a lightering plan and engaged a crane barge with a clamshell bucket to transfer the loose spoils to another barge.

As a precaution,Global positioned high capacity pumping equipment on location. Draft measurements monitored throughout the lightering indicated the presence of an unbalanced load in the barge. During the operations significant damage to the barge was observed. This information was incorporated into the lightering plan to ensure the safety of the operation. Following the lightering procedure,Global removed the damaged bin rails and prepared the barge for transit through the Ballard Locks.

The pier sustained significant damage to the fender piling from the capsizing barge. Global’s team quickly developed and proposed a repair plan. Following approval,Global removed the damaged piling and drove new steel replacements.

Additionally,it was determined a new fender system was required before loading operations could resume. Global’s team designed and installed an approved fender system allowing the project to continue tunneling operations.

Global provided salvage,environmental,and marine construction services to expedite and safely resolve this unexpected incident.

Pier 54 Pile Replacement & Telescopic Pile Stubbing

Global Diving & Salvage,Inc. was contracted to provide diving services to assist with removal and replacement of Teredo worm damaged piling under Pier 54 along the Seattle waterfront. Damaged piling were cut off at or below mudline and replaced with new telescopic pile stubs. The galvanized pile stub is made up of an inner and outer section. The stub was maneuvered into position using floats,the base was lowered to the divers who slid it over the exposed,prepared,pile and secured it in place. The telescopic stub (inner section) was secured to the underside of the pile cap. The inner and outer sleeves were then welded together. In total,approximately 45 piles were repaired / replaced.

ROV Assisted Derelict Fishing Net Removal

Over 5,600 derelict fishing nets had been removed from Puget Sound water by volunteer divers from depths up to 105 feet. Yet there remains many more in deeper water. Global Diving,working with Natural Resources Consultants for the Northwest Straits Foundation developed custom tooling and a ‘plan’ to remove the nets using a SAAB Cougar and Falcon ROV. First the ROV’s surveyed the nets,then a plan was developed,utilizing the tooling to gather and cut the nets free from the obstacles they snagged on. Once gathered and free,they were connected to the line from a vessel mounted crane. The balls of net were raised to the surface for proper disposal.

This pilot program was developed to test the feasibility and develop the tools and methods required for this removal.

Seafair Breasting Barge Installation

Global’s Marine Services Division provided breasting barges and security boom to support to arrival of the US Navy ships that took part in the Sea Fair celebration in Seattle. Sectional barges sections were deployed into the water,yokohama fenders affixed to the barge and the barges were secured to the pier piling to fend the Navy ships from the pier. Once at berth,the ships were surrounded with a ‘security’ boom to prevent water craft from coming alongside the vessel.

Rocky Reach Spillway Apron Underwater Concrete Repair

We were contracted to preform an underwater concrete repair to the spillway baffle under spill gate 3,and preform an inspection of the spill way and dentate from spillway 2-8 and 9-12. the spillway was separated into two sections by a fish ladder between Bays 8 and 9. The perimeter of the eroded areas were delineated using an U/W track creating a key way,ensuring a minimum depth of repair,throughout the area. Divers used rivet busters to remove concrete from the key cut as well as from under exposed rebar to ensure encapsulation and to allow couplers and new rebar to be added in areas wee eroded. Divers then used a 20k hydro blaster to wash away loose material and marine growth. Once the areas were prepared and cleaned,custom form tops were installed. The forms were made to fit the round side of the baffle that was approx. 18’x20′ and was rock anchored in place. Eight cubic yards of high strength concrete was then pumped into the form. While the concrete cured in the forms,the inspections were carried out of the stilling basin floor. The forms were removed and the project demobilized.

Salvage of Yacht Destroyed By Fire in Roche Harbor

In the morning hours of July 10,2013,while moored at a dock in Roche Harbor Marina in the San Juan Islands,a newly built 85’ motor yacht caught fire and burned. Firefighting efforts ensued however the vessel sank at her mooring. Responders deployed oil containment boom around the scene which has been very effective in containing debris and fuel from the vessel.

Global Diving & Salvage,Inc.,under contract to the yacht’s owner,mobilized personnel and resources from its Seattle headquarters and Anacortes operations to respond to the incident,conducted an underwater survey of the vessel and mitigated the environmental threat posed by the vessel. Global’s Marine Casualty Response group developed a salvage plan which was approved by the State and Federal agencies overseeing the incident.

Global contracted Manson Construction to provide crane lifting services utilizing specialized salvage rigging equipment designed and maintained by Global. A wide range of emergency response equipment is maintained by Global on 24 hour standby in the Seattle warehouse and other regional bases.

Under direction of Global’s Salvage Master diver’s rigged the hull of the yacht,which was raised from the seafloor and returned to a floating condition. Crews removed the remaining fuel and HAZMAT,it is inspected and deemed safe. The vessel was towed to a boatyard where it was removed from the water.

Skagit River Bridge Collapse

On Thursday,May 23,2013 while traveling on the southbound lane of Interstate 5,a truck hauling a heavy and oversized load struck the support structure of a bridge crossing the Skagit River in Mt. Vernon,WA. The damage inflicted by the truck caused the 160 foot long four lane span to collapse into the river below,completely severing the north and south bound lanes of the major west coast interstate highway.

Global Diving & Salvage,Inc.,under contract to Atkinson Construction,worked around the clock for 13 days under direction of the Washington Department of Transportation and the National Transportation Safety Board (NTSB) to provide diving and salvage services throughout the investigation and debris recovery phase of the project.

Dive operations in the river were complicated by high river currents resulting from spring runoff conditions. The salvage operations included a detailed underwater survey of the downstream edge of the wreckage to ensure that it was safe to bring demolition equipment alongside. Motor vehicles caught up in the collapse were recovered. Working closely with the NTSB the bridge wreckage was cut and rigged out of the river. With the river cleared of debris,an underwater inspection of the concrete bridge piers was performed in order to confirm the structure remained viable for bridge reconstruction.

Cushman Dam Diverter Structure

We removed loose rock and sediment from river bottom to allow for placement of new foundation structure for fish sorting facility. Divers tremied concrete into base of foundation to secure in place.

All dive operations were carried out from shore on downstream side of dam. Crane allowed equipment to be moved from crest to work site,personnel have to access work area via stairway.

River Intake Sediment Removal

Global supplied divers to hand operate suction dredge hose for the removal of accumulated river sediment from cooling water intakes at the mothballed N Reactor on the Hanford Nuclear Reservation.