Underwater Expertise for Complex Inspection, Construction, and Repair
Brennan provides commercial diving, underwater inspections, nuclear diving, welding, and marine construction support with ADCI-certified divers across North America.
Built for Challenging Underwater Environments Est. 1919
Underwater work demands more than diving capability. It requires disciplined planning, specialized training, clear communication, proven safety systems, and the ability to perform in environments where visibility, access, currents, contamination, and infrastructure conditions can change quickly.
Brennan’s commercial diving teams are trained for that level of complexity. With one of the largest union commercial dive teams in the country, our crews support inspection, construction, maintenance, repair, and documentation needs in rivers, lakes, reservoirs, ports, dams, power generation facilities, industrial sites, and other near-zero-visibility conditions.
Because our divers are integrated into Brennan’s marine construction, dam, environmental, harbor, and energy infrastructure teams, clients gain more than a dive crew. They gain a collaborative partner that can inspect, diagnose, plan, build, repair, and document the work with every resource available.
Specialized Diving, Inspection, Survey, and Underwater Construction Support Commercial Diving Services
Brennan provides commercial diving services across the full project lifecycle, from planning and condition assessment to construction, repair, verification, reporting, and long-term maintenance.
Brennan is approved to perform safety-related work in accordance with ASME NQA-1 (2022), 10 CFR 50 Appendix B, and 10 CFR Part 21, and is certified to ISO 9001 (Quality Management), ISO 14001 (Environmental Management), and ISO 45001 (Occupational Health and Safety Management) standards.
Safety-Driven Commercial Diving Backed by Proven Standards Dive Safety & Compliance
Professional diving is safety-critical work, and Brennan treats safety as the foundation of every underwater project. Our dive team operates with disciplined planning, experienced supervision, thorough hazard assessment, and compliance-focused procedures designed to protect people, assets, and project outcomes.
Brennan’s safety culture is built for complex underwater environments, including active waterways, industrial facilities, confined spaces, contaminated sites, power generation facilities, and near-zero-visibility conditions. Every dive plan is developed around the work being performed, the conditions below the surface, and the risks that must be controlled before the job begins.
Key Capabilities
- ADCI-certified commercial divers
- Dive planning and hazard assessment
- Project-specific safety planning
- Compliance-focused dive operations
- Confined space diving support
- Contaminated water diving support
- Near-zero-visibility diving procedures
- Emergency response planning
- Experienced dive supervision
- Coordination with facility safety teams
- Detailed pre-task planning and communication
Specialized Diving Services for Nuclear Power Facilities Nuclear Diving
Nuclear power generators require commercial divers with the training, discipline, and quality-focused execution needed to work in highly controlled environments. Brennan provides specialized nuclear diving services for inspection, maintenance, repair, construction support, and critical infrastructure needs at nuclear generation facilities.
Our commercial divers and project teams understand the importance of safety, documentation, regulatory expectations, and coordination with facility teams. From intake and outfall systems to fuel transfer systems, traveling water screens, valves, seals, reactor components, and visual examinations, Brennan supports nuclear facility work with precision and control.
Brennan is approved to perform safety-related work in accordance with ASME NQA-1 (2022), 10 CFR 50 Appendix B, and 10 CFR Part 21
Key Capabilities
- Nuclear diving
- VT-1 and VT-3 visual examinations
- Intake and outfall inspections
- Fuel transfer system support
- Traveling water screen work
- Valve and seal support
- Reactor component support
- Cooling pond and infrastructure support
- Coating application
- Fish protection systems
- Maritime security barrier support
- Quality-focused documentation and reporting
Underwater Construction Support for Complex Marine Projects Marine Construction
Brennan’s commercial diving teams support marine construction projects by extending construction capability below the waterline. Our divers work with Brennan’s marine construction crews to inspect, prepare, repair, install, and verify critical infrastructure in underwater environments.
This integrated approach helps owners, engineers, and contractors move from discovery to construction with fewer handoffs. Whether the project involves a bridge, pier, dock, dam, terminal, intake, outfall, shoreline structure, or industrial waterfront, Brennan brings both the underwater expertise and the marine construction capability to complete the work.
Key Capabilities
- Underwater construction
- Underwater repairs
- Marine structure inspections
- Pile and pier support
- Bridge and dock support
- Intake and outfall support
- Cutting, welding, and installation support
- Concrete and steel repairs
- Demolition support
- Construction verification
- Coordination with marine construction crews
Clear, Reliable Assessments of Critical Underwater Assets Underwater Inspections
Underwater inspections help owners understand the condition of structures and systems that cannot be fully evaluated from above the surface. Brennan provides commercial dive inspection services for bridges, dams, docks, piers, intakes, outfalls, pipelines, tanks, marine terminals, industrial facilities, and other water-based infrastructure.
Our inspection teams document existing conditions, identify defects, support maintenance planning, and help clients make informed decisions about repair, replacement, construction, and long-term asset management.
Key Capabilities
- Underwater structural inspections
- Bridge and pier inspections
- Dam inspections
- Intake and outfall inspections
- Pipeline and utility inspections
- Tank and confined space inspections
- Dock and terminal inspections
- Damage assessments
- Maintenance inspections
- Pre- and post-construction inspections
- Photo, video, and written documentation
Advanced Tools for Better Visibility Below the Surface Underwater Imaging & Technology
Underwater conditions can make it difficult to see, measure, and understand what is happening below the surface. Brennan uses advanced underwater imaging and inspection technologies to improve visibility, support decision-making, and provide clearer documentation for complex projects.
From ROVs and sonar to stereo cameras and detailed diver-assisted documentation, our teams help clients evaluate structures, monitor work progress, identify hazards, and verify completed work in environments where visual access is limited.
Key Capabilities
- ROV inspections
- Acoustic imaging
- Stereo cameras
- Side scan sonar
- Multibeam sonar support
- Underwater video
- Underwater photography
- Diver-assisted imaging
- Sonar-based condition assessments
- Near-zero-visibility support
- Inspection technology integration
- Digital documentation and reporting
Survey Data That Supports Planning, Construction, and Verification Hydrographic Survey
Brennan provides hydrographic survey services that help clients understand underwater topography, site conditions, sediment volumes, structure locations, and construction progress. Our survey teams support marine construction, dredging, environmental remediation, dam work, commercial diving, and infrastructure projects where accurate underwater data is essential.
Hydrographic survey gives owners and project teams the information they need to plan work, track progress, verify quantities, assess conditions, and document final results.
Key Capabilities
- Hydrographic survey
- Bathymetric survey
- Pre- and post-construction surveys
- Dredging quantity surveys
- Sediment volume calculations
- Structure and obstruction mapping
- Survey support for capping and remediation
- Survey support for marine construction
- Progress verification
- Final condition documentation
Clear Documentation That Helps You Act With Confidence High-Quality Deliverables
The value of underwater work depends on the quality of the information delivered afterward. Brennan provides high-quality deliverables that help owners, engineers, facility teams, and stakeholders understand what was found, what was completed, and what decisions should come next.
Our deliverables can include detailed reports, photos, video, drawings, condition summaries, survey data, inspection findings, repair documentation, and recommendations tailored to the project. The goal is simple: give clients clear, usable information that supports planning, maintenance, repair, compliance, and long-term asset management.
Key Capabilities
- Detailed inspection reports
- Photo and video documentation
- CAD drawings
- Survey data and mapping
- Condition assessments
- Repair documentation
- Construction verification reports
- Defect identification
- Maintenance planning support
- Digital project records
- Clear communication for owners and engineers
More Than Divers. A Fully Integrated Underwater Services Partner. Why Brennan for Commercial Diving?
Commercial diving work is often only one part of a larger project. Brennan brings diving, marine construction, environmental, dam, energy, harbor, survey, and inspection capabilities together under one experienced team.
That means our divers can identify an issue, our engineers and project teams can help plan the solution, and our construction crews can help complete the repair. This integrated approach reduces handoffs, improves communication, and gives clients a partner that understands the work above and below the waterline.
What Sets Brennan Apart
- More than 120 ADCI-certified commercial divers on staff
- Award-winning safety performance in safety-critical environments
- Transparent project communication from project design through closeout
- In-house NQA and Total Quality Management programs to support complex commercial diving operations and environments
- Integrated marine construction, dam, environmental, and energy infrastructure support
- Experience in near-zero-visibility and difficult-access environments
- Clear, high-quality deliverables for owners, engineers, and stakeholders
Total Quality Management Across the Organization
- ISO 9001 (Quality Management Systems)
- ISO 14001 (Environmental Management)
- ISO 45001 (Occupational Health and Safety Management)
- ASME NQA-1 (2022), 10 CFR 50 Appendix B, and 10 CFR Part 21
Whether you need an underwater inspection, nuclear diving support, hydrographic survey, marine construction assistance, advanced imaging, or a commercial diving team that can deliver clear documentation, Brennan has the people, equipment, and experience to help you move forward safely and confidently.
What Our Customers Are Saying Client Testimonials
Serving Coastal & Inland Waterways Office Locations
Bring Brennan Into Your Commerical Diving Project
Whether you need an underwater inspection, nuclear diving support, hydrographic survey, marine construction assistance, advanced imaging, or a commercial diving team that can deliver clear documentation, Brennan has the people, equipment, and experience to help you move forward safely and confidently.
Stay Connected With Brennan
Sign up for Brennan’s e-newsletter to receive company news, project updates, announcements, insights, and other information from across our work.