Our mission is to meet every customer’s unique needs, from project conception to completion and beyond. Our team delivers what you need when you need it. Most importantly, we do not just talk about projects; we have done the work.

  • Diving and Marine Construction
  • Maritime Security Barrier Systems
  • Underwater Cable Installation and Repairs
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Military Installations

The Need:
 After the October 2000 USS Cole terrorist attack, the US Navy ordered marine security barriers to establish a defense perimeter at naval bases worldwide.

What We Did: The Harbor Offshore Barriers team installed and continues to maintain US Navy barrier systems in the continental US, Guam, Hawaii, Japan, Iraq, Crete, and Spain. The US Navy consistently rates Harbor Offshore Barriers performance as Excellent or Very Good, resulting in an award bonus for 95% of 26 task orders from 2003 to 2014.

LNG, Oil Production and Transportation Facilities

The Need:
 Offshore and coastal oil and gas facilities require significant construction and operational investment. Protecting these assets from malicious and destructive attacks by installing marine security barriers demonstrates to investors and insurers that the operating owner is a credible business directly addressing high risks to operational stability. Technology driving the expansion of floating production, storage, and offloading (FPSO) and floating, storage, and regasification units (FSRU) alone increases demand for meeting the highest marine security standards.

What We Did: Harbor Offshore Barriers specialists are using high performance computer modeling to examine barrier reliability and efficiencies under simulated conditions to design an offshore system. These include sea and weather conditions, water depths, and wave action to replicate “real-world” engineering requirements.

Ports and Marinas

The Need:
 Port operations, whether for containerized, bulk, or break-bulk cargo, cruise ships, fishing vessels and pleasure boats, by and large take place in urban areas of the world’s cities. The threats of sabotage, theft, smuggling and lethal explosions need to be deterred by a visible floating fence to keep out intruders while allowing vessel traffic operations to proceed as scheduled.

What We Did: While patrol vessels rapidly move to an area under threat, Harbor Offshore Barriers’ maritime security systems are demarcation barriers beyond which no one should pass. They provide that extra measure of security to deter even the idea of attacking a vessel in port or traffic channel while complementing marine patrols.

Nuclear Power Plants

The Need:
 Government agencies are requiring on-lake nuclear power plant owners to install underwater barriers to prevent access to intake pipes.

What We Did: Harbor Offshore Barriers’ site visit team determined that the lake bottom and environmental conditions required a customized 500 ft (152 m) structure. The system included a single 100 ft (30.5 m) bridge span unit and a gate. The client found that we were the only company that could meet the requirements for their nuclear power plant.


The Need:
 The US government has found that it is in the public’s interest to protect dams from domestic and foreign terrorist attacks. An attack would cause massive flooding, loss of life and property and destroy hydroelectric power facilities.

What We Did: The US Bureau of Reclamation engaged Harbor Offshore Barriers to install waterside barrier systems for several dams and waterways. Our project manager successfully designed and executed a logistics strategy for transporting large components and equipment to remote locations.

Tanner Electric Cooperative

General scope of the project:
In summary, this project consisted of providing the services and equipment necessary to install approximately 13,000 feet of marine cable between Luhr Beach and a point on the South end of Anderson Island, WA in accordance with applicable permits and technical requirements furnished by the owner and its engineer.

The nature of the work that was performed: Harbor Offshore, Inc. managed and coordinated all aspects of this project; coordination of horizontal drilling operations, vault installation and final testing of submarine cable. HOI utilized its specialized cable lay installation equipment, barges, ROV’s and dive support vessels to lay the cable within its prescribed corridor.

CIRI-Cruz Project

General scope of the project:

In May of 2012, Cook Inlet Regional Inc. contracted with Cruz Construction of Palmer, Alaska to install two, 18,000 foot, 3-core single armor, 35 kv power cables between Anchorage and Fire Island as feeder cables for a new wind farm.

The nature of the work that was performed:
The crossing was tidal, with a 30 foot range. The barge would be dry twice a day and land based burial equipment would bury the cable at low tide.

Transbay Cable Project

General scope of the project:
Harbor Offshore, Inc was contracted to assist in the installation of 53 miles of submarine cable from Pittsburgh, CA to South San Francisco, CA.

The nature of the work that was performed: Harbor Offshore, Inc. provided six shallow water and deep water dive spreads crewed for 24/7 operations within a week’s time to support the laying of 53 miles of submarine cable. These operations included cable sled installation and retrieval, surveying, u/w video, sub mar mat placement, and extensive cable burial operations performed by hand jetting.

Back Island Cable

General scope of the project:
Harbor Offshore provided highly valuable technical support during planning and execution of this project. Personnel with Harbor Offshore participated in the mobilization of equipment and the on-water installation. SAIC personnel installed the array and Harbor Offshore installed the umbilical’s and shore cables. Harbor Offshore provided the key members of the submarine cable team, during all phases of the installation.

The nature of the work that was performed:
Install (2) shore connections consisting of a 1645 foot umbilical, 10,000 lb clump weight in 1400 feet of water and a 30,000 foot power and data cable to shore on Back Island.

Century Link – San Juan Island

General scope of the project:
On November 5, 2013, there was an outage of the cable between Lopez Island and San Juan Island. The repair spread was working onsite by November 10 and the repair was completed by the 16th. Harbor Offshore provided highly valuable operational and technical expertise during the rapid planning and execution of this project. Harbor Offshore organized and directed the
mobilization of equipment and the conducted the successful on-water repair. This involved the utilization and direction of numerous subcontractors with equipment and specialized capability in use of dual tractor tugs, hi-current ROV, derrick barge, acoustic subsea positioning, surface positioning, mixed gas diving and fiber optic splicing.

The nature of the work that was performed:
Recover severed cable end in 300 feet of water. Splice repair cable to end and relay new cable to Lopez Island. This was done in an active cable crossing with 2 other live power cables in the immediate area. The entire operation was performed without anchors by holding station during the splice and lay. Currents were measured as high as 3.5 knots

Chief Joseph Dam

General scope of the project:

Provide commercial dive labor, equipment, and materials in support of underwater operations involving the installation of gas deflectors on the face of the dam.

The nature of the work that was performed:
HOI personnel incorporated the use of lasers, drill templates, hydraulic and pneumatic tooling, U/W video equipment, U/W burning and welding techniques, and provided the necessary experienced dive personnel to assist in demolition, rebar installations, form work, and all the other facets involved in this highly diver involved project. Some of the work encompassed asbuilding to confirm designed component fit, structural analysis, identification and removal of formwork, rebar installations, extensive concrete core drilling and concrete repairs, numerous installations and sealing of cofferdams and bulkheads. HOI worked extensively with project engineers to ensure the installation of the gas deflectors and associated pieces would fit correctly at their precise destination.

Elwha River Restoration Project

General scope of the project:
Installation of an 800’ x 24” HDPE submarine ocean outfall.

The nature of the work that was performed:
In the role of prime contractor, HOI coordinated overall efforts including the project QC/QA program, SWPPP program, subcontractors, vendors, performed offshore sheet pile driving, dive operations, tug operations and overcame unique project logistics and inclement weather issues.

Priest Rapids Dam Project

General scope of the project:
HOI was awarded the contract for the removal of debris on the dam spillway and repair of the damaged concrete within the seasonal fish closure timeline without posing a threat to the sensitive environmental zones adjacent to the project site.

The nature of the work that was performed:
HOI personnel were tasked with conducting various modes of underwater construction in order to meet the stringent project timeline and meet the client’s needs. HOI divers conducted underwater surveys, removed 8’+ boulders from the project site, conducted 25k hydroblasting operations, performed numerous pneumatic chipping/drilling patterns, installed rebar cages, installed/custom fit forms as needed, and conducted sequential underwater concrete pours utilizing boom trucks to deliver grout to limited access locations.

Hueneme Outfall Restoration

General scope of the project:

Installation of a 4600’x 30” weight coated outfall pipeline and diffuser section.

The nature of the work that was performed:
Divers assisted in HDD operations, surveyed and constructed HDPE transition template, installed transition spool piece, surveyed ballast rock installation, and installed 32- 80’ spool pieces to complete outfall installation. These operations required surveying, u/w video, and extensive use of custom built hydraulic horses to assist in flange-ups in various sea states.

Platform Grace – Phase 1 Inspection

General scope of the project:

The project scope tasked HOI personnel to perform the following:
• General Underwater Visual Survey
• Cathodic Protection Survey
• Marine Growth Survey
• Debris Survey
• Scour Survey
• Weld Inspection at Five Suspect Joints (Mag. Particle)
• Corrosion Inspection at five members per level.
• Flooded Member Survey (ASNT Level II)
• Existing/New Damage Survey

This work was completed safely and efficiently using compressed breathing air for all diving work down to (-) 165’ and compressed gas (14% oxygen and 86% helium) from (-) 165’ down to (-) 300’.