Diver performs underwater inspection of the University of WA research vessel the Tommy Thompson.
Project Tag: Pacific Northwest
Global Diving & Salvage,Inc. performed an underwater video inspection and cleaning on the water intakes at the Columbia River,WSU facility,in Richland,WA. The purpose of the dive was to inspect and clean the intake screens along with removing any extraneous debris present. Dive operations were conducted from a truck dive station,and the diver was working in water depths of 10-12ft with a visibility of approximately 10ft.
A live-aboard vessel sank at it moorage on the Duwamish River. Global Diving was contracted by Department of Ecology to mitigate any potential fuel release as well as raise the vessel and remove it from the water. Containment boom was deployed around the vessel as well as various locations around marina to mitigate the spread of fuel in the river current. The fuel vents and caps were sealed. Lifting straps were run under the vessel. A derrick was brought to the site to lift the vessel off bottom. Once on the surface,water was pumped from the hull.
Project involves diver direction of a air lift to remove material behind damaged section of cellular bulkhead. Once materials are removed from behind bulkhead divers will cut damaged sheet pile to be removed from the water. Assistance with dredging and pile cutoff will take place from contractor platform.
Divers will also weld repairs over damaged joints in bulkhead wall. All work associated with sheet pile repairs will be performed from Global provided platform.
In 1929 the City of Portland built Bull Run Dam 1 on Federally protected and restricted land,the Bull Run Watershed. This complex,Bull Run Dam 1 and 2 is a significant source of potable water for the City of Portland and the surrounding area. Due to its location of Federally protected land and fact that we are working in potable water great care has been taken during the project,from complete decontamination of all diving gear and related equipment that enters the water,to complete containment for all mechanical equipment on site. Access to the site is extremely limited,there is no thru access across the top of the dam,all of the equipment had to be staged on top of the dam. The water level has fluctuated over 40 feet during the project,making access to the water extremely difficult.
The dam has seven slide gates mounted to the face of the dam inside a trashrack enclosure. These gates,located at various levels allow the operators the control the flow of water as well as the level (temperature) of the water as it moves through the system. During the project the existing trashracks as well as the supporting beams were found to be severely rusted. They are all being replaced with new galvanized beams and panels. One existing gate,#6 had severely eroded concrete behind the frame where it mounts to the dam wall allowing water to pass even when the gate was closed. Part of the project was the complete removal of the gate,drilling out of the original anchor bolts,repair to the concrete and reattachment of the gate to the dam. This entire process was carried out inside of the trashrack enclosure Tracks were mounted to the underside of the enclosure and the gate was moved to the outside edge where it lifted and set on deck for cleaning and storage while the concrete repairs were being made. The gate was reinstalled and secured with new anchors.
The existing materials were all the original installation,the nuts which secured the stem to the gate were severely corroded and had to be cut off. All of the existing stems were removed and disposed of as well as all of the stem guides and the actuators mounted on the surface. New stems guides were mounted to the face of the dam. New stems were attached to the guides. As stated above,all of the work was carried out inside of the trashrack structure,all of the parts and pieces had to be lowered into the water then cross hauled under the overhead structure and lowered into place. Once installed through the operator floor the stems were attached to new operators and connected to the gate itself. All gates were fully function tested for proper operation.
Part of the project also involved repairs to the spillway. Rolling scaffolding was raised and lowered on the curved spillway surface as needed to access the area to be repaired.
Global Diving & Salvage,Inc. is contracted to provide 40 trained responders to the Marine Spill Response Corporation (MSRC) in the event of an oil spill in the Northwest Region. Crews,ranging from field technicians to licensed captains,hone their skills and stay up to date on their required certifications through annual trainings and practice drills on local MSRC vessels.
The existing sewer line on the northwest corner of Mercer Island was installed in the mid-1950s,and is constructed of asbestos-cement (AC) material. The line has been suffering ongoing pipeline deterioration,capacity deficiencies,and other operation and maintenance problems. Manson Construction was awarded the contract to replace this portion of the sewer line with cast iron pipe and selected us to provide the diving services. This project will extend over a two-year period and involves the replacement of over 7,000 feet of pipe with 32 side sewer connections.
We are working very closely with Manson during all aspects of the project,including: installing both gravity and force main pipes,aligning and connecting the side sewer piping,assisting with hand dredging under docks and in tight areas where the derrick cannot access,and making the physical transition from the existing line to the new piping.
We provided all project management,diving services and topside support for this location as part of an overall three-outfall repair project. Work done at Alki involved the installation of five new anode sleds. Tabs were welded to the existing outfall,and leads connected the new anode sleds to the outfall. At the conclusion of the installation,measurements were taken at 22 locations along the outfall to verify the increased cathodic protection.
Welding was performed in 100 feet of water,as was setting of the five anode sleds.
The Maritime Center was recently built in Port Townsend. The HVAC system was designed to take advantage of the cool waters of Puget Sound through a heat exchanger mounted on the piling at the end of the pier. We secured the stainless steel components to the piling and connected HDPE piping under the pier to the HVAC equipment located inside the building.
A tool was inadvertently dropped into the primary clarifier unit,blocking mixing equipment. Within two hours of the initial call,Global responded with HAZMAT diving equipment,the diver removed the obstruction,and verified proper operation of the mixer.