Reliable Underwater Bridge Inspections You Can Trust
Our underwater bridge inspections are performed by FHWA-certified bridge inspectors using commercial hard-hat, surface-supplied diving systems with umbilical air supply and continuous diver-to-topside communications. Beneath the waterline, bridge components are constantly exposed to conditions that can compromise their structural integrity, from scour and corrosion to impact damage and material deterioration. Because many of these vulnerabilities remain hidden from view, underwater inspections are a critical part of maintaining public safety, structural reliability, and compliance with regulatory standards.
Comprehensive Inspection Services
We provide a full range of underwater inspection services, all conducted by qualified commercial divers and bridge inspection professionals:
Substructure Condition Assessments
Our divers perform direct, tactile inspections of submerged components. This includes piles, piers, abutments, footings, and scour protection. Using manual probing, cleaning, and measurement techniques, we identify cracking, spalling, displacement, corrosion, and other signs of deterioration with precision.
Scour and Channel Evaluation
We inspect for scour, erosion, and channel changes that may undermine the stability of bridge foundations. Our divers use manual sounding rods and depth measurements to document channel profiles and detect changes in bed conditions over time.
Structural Integrity and Section Loss Assessment
When steel or metallic elements are present below the waterline, we utilize ultrasonic thickness gauges to measure remaining wall thickness and section loss. This data supports accurate load evaluations, repair prioritization, and long-term asset management decisions.
Clear Documentation and Reporting
Every inspection includes a detailed report that documents existing conditions, photographic and video evidence, ultrasonic data (if applicable), and practical maintenance or repair recommendations. Our reporting is formatted to comply with NBIS and FHWA standards, making integration into your bridge inventory seamless.
Our Approach: Hands-On, Proven, and Precise
Unlike technology-driven surveys, our approach prioritizes direct human assessment because the most accurate information still comes from skilled professionals working hands-on in the water.
Our divers use:
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Manual tactile inspection techniques to locate and assess damage even in zero-visibility environments.
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Probe rods, scrapers, and measuring tools to expose and measure deterioration.
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Ultrasonic thickness gauges for accurate steel section measurements.
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Underwater video and still photography to document findings and support engineering decisions.
This approach ensures that every inspection result is reliable and not based on assumptions or remote sensing alone.
Safety and Compliance First
All work is performed in accordance with ADCI (Association of Diving Contractors International) standards, OSHA safety protocols, and FHWA/NBIS bridge inspection requirements. Our procedures are built around diver safety, data accuracy, and regulatory compliance with additional precaution taken in challenging conditions such as high currents, confined spaces, or poor visibility.
Beyond Routine Inspections
In addition to standard inspection services, we also offer:
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Post-Flood and Emergency Assessments – Rapid-response inspections following scour or impact events.
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Construction Support and As-Built Verification – Independent verification of new underwater construction work.
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Repair Support Services – Assistance with targeted remediation or maintenance planning.
Frequently Asked Questions (FAQ)
How often should underwater bridge inspections be performed?
Most bridges require underwater inspections at least once every 60 months (5 years), as recommended by the National Bridge Inspection Standards (NBIS). However, structures in high-risk environments, such as those with fast-flowing water, scour-prone foundations, or heavy traffic loads, may benefit from more frequent inspections or additional follow-ups after major weather events.
What’s included in an underwater bridge inspection?
A standard inspection includes a visual and tactile assessment of all submerged structural components, measurement of scour depth and channel conditions, documentation of deterioration or defects, and, where applicable, ultrasonic thickness measurements of steel or metal elements. All findings are compiled into a comprehensive, NBIS-compliant report with photos, video, and recommendations.
Can inspections be performed in zero visibility conditions?
Yes. Our divers are trained and equipped to work safely and effectively in low- or zero-visibility water using manual touch techniques, reference measurements, and continuous diver-to-surface communication. We also use underwater video and ultrasonic data to supplement tactile observations when visibility is limited.
Will my inspection report meet DOT or FHWA requirements?
Absolutely. All of our reporting is prepared in compliance with FHWA and NBIS standards. We deliver documentation that aligns with state DOT requirements and can be directly integrated into your existing bridge management systems.
What happens if a serious defect is found?
If a critical issue or immediate hazard is discovered, we will notify you immediately and provide detailed recommendations for next steps. We can also support you with follow-up inspections, repair planning, and coordination with engineering teams to ensure that corrective actions are taken promptly.