Recent global UUV incidents have shown the critical asymmetric threat presented by UUVs, with low-cost, commercially available or locally developed systems able to penetrate defended harbors, approach high value assets, and target critical infrastructure, to significant demonstrated effect. Reliable and persistent non-kinetic UUV defeat (disrupting or disabling without explosives or harmful emissions) has become a mission-critical requirement. 
Developed by ThayerMahan, SeaGuard™ is an operationally validated non-kinetic UUV defeat system. A modular, scalable security solution, SeaGuard delivers unmatched underwater threat mitigation for military and commercial port facilities, moored strategic assets, and critical infrastructure.
Developed by ThayerMahan, SeaGuard™ is an operationally validated non-kinetic UUV defeat system. A modular, scalable security solution, SeaGuard delivers unmatched underwater threat mitigation for military and commercial port facilities, moored strategic assets, and critical infrastructure.
OVERVIEW
Protection for Critical Undersea Infrastructure
SeaGuard™ is a rapidly deployable, mission-durable, environmentally responsible underwater barrier system. Designed to protect mission-critical assets below the waterline, SeaGuard is ideal for ports, offshore installations, military operations, and construction zones. The system defends against:
CORE CAPABILITIES
Subsea Barrier
SYSTEM PERFORMANCE
Field Tested. Mission-proven. Always ready.
Key System Capabilities
DEFENSE & SECURITY APPLICATIONS
A Non-Kinetic Solution for Underwater Threats
Protection for Critical Undersea Infrastructure
SeaGuard™ is a rapidly deployable, mission-durable, environmentally responsible underwater barrier system. Designed to protect mission-critical assets below the waterline, SeaGuard is ideal for ports, offshore installations, military operations, and construction zones. The system defends against:
- Unmanned Underwater Vehicle (UUV) threats
- Unauthorized diver or swimmer intrusion
- Intentional acts of tampering or sabotage
- Operational disruption during sensitive missions
CORE CAPABILITIES
Subsea Barrier
SeaGuard creates a barrier that:
- Disrupts and defeats UUVs
- Deters diver access
- Protects berths, cable landing stations, intakes, and structures
This capability provides a non-kinetic layer of defense around high-value underwater assets without introducing fixed hazards.
SYSTEM PERFORMANCE
Field Tested. Mission-proven. Always ready.
Existing maritime security systems lack a proven defeat capability - leaving critical infrastructure vulnerable.
SeaGuard™ is the only operationally validated and exercise-proven system capable of performing non-kinetic UUV defeat in a mission-critical homeland defense operational environment. It has achieved reliable and measurable defeat performance across all evaluated exercises and trials, demonstrating:
SeaGuard™ is the only operationally validated and exercise-proven system capable of performing non-kinetic UUV defeat in a mission-critical homeland defense operational environment. It has achieved reliable and measurable defeat performance across all evaluated exercises and trials, demonstrating:
- Fleet-relevant and interagency environment operations
- Proven Reliability and Endurance
- Maintainable and Logistically Supportable Architecture
- Integration-Ready status for existing and emerging Fleet CONOPS
Key System Capabilities
- Physical defeat coupled with disruption provides comprehensive UUV mission-kill.
- Creates a multi-purpose subsea barrier
- Deters divers and defeats UUVs
- Non-permanent, rapidly recoverable, environmentally responsible deployment
- Temporary/expeditionary or permanent configurations
- Water depth 10-50+ m (site dependent)
- Individual barrier lengths up to 1500m
- Additional barriers can be deployed to add defensive redundancy
- Modular configurations for ports and offshore structures
A Non-Kinetic Solution for Underwater Threats
As threats to subsea infrastructure continue to evolve, SeaGuard provides a flexible, non-kinetic option for protecting assets and infrastructure, including:
- Naval bases and military installations
- Ports and harbors
- Offshore energy and communications infrastructure
- Temporary high-value maritime operations
SeaGuard acts as both a deterrent and a protective barrier, reducing vulnerability while preserving port operability and environmental compliance.
WHY THAYERMAHAN
Purpose-Built for the World Below the Surface
Frequently Asked Questionss
WHY THAYERMAHAN
Purpose-Built for the World Below the Surface
- Immediate fielding available: Supports urgent operational needs (UONs) and contingency requirements
- Accelerated scaling: Enables rapid expansion to safeguard additional high-risk sites.
- Modular security: Used with proven passive sensors and third-party active sonar to enable a detect-classify-defeat chain.
- Force protection at scale: Enhances mission assurance, reduces risk to personnel, and protects national infrastructure from emerging underwater threats.
- Proven performance: Recognized across multiple defense missions
- NO ONE CAN HEAR — OR PROTECT — LIKE WE CAN.
- ThayerMahan is the premiere provider of end-to-end unmanned acoustic intelligence solutions. We deliver fixed and mobile undersea domain awareness from scalable, fully mature, productized platforms. Deployed together, our acoustic intelligence solutions detect undersea threats, and our SeaGuard system secures your critical assets.
Frequently Asked Questionss
Has SeaGuard been tested?
Yes. SeaGuard™ is the only system of its kind, and has demonstrated repeatable, operationally validated defeat performance across all evaluated exercises and trials.
Is SeaGuard in use?
Yes. ThayerMahan has fielded technology capable of protecting critical ports, assets, and key infrastructure across U.S. government and commercial operators, with systems actively deployed today.
Can I Order a SeaGuard System?
Yes. ThayerMahan's SeaGuard system is open for orders from Government and Commercial customers. Contact our Team to begin your journey towards enhanced security with non-kinetic UUV defeat.
