Underwater & Marine

Underwater construction activities can generate vibrations that travel through the water as shock waves. These waves, measured as pressure and commonly referred to as overpressure, can significantly affect marine life and surrounding ecosystems. When overpressure levels become high, they can trigger physiological or behavioral changes in fish and marine mammals, potentially causing injury, disrupting normal functions, and negatively impacting long-term health and reproduction. Elevated overpressure can also interfere with the sonar and communication abilities of marine mammals and damage sensitive habitats such as coral reefs.  

Even construction activities occurring near a body of water can transmit vibrations into the aquatic environment, extending their influence beyond the immediate work zone. To help mitigate these impacts, bubble curtains are often deployed to reduce and contain overpressure levels. However, even with best-practice mitigation in place, underwater and near-water construction activities can still produce effects that persist and accumulate over time—making careful monitoring and environmental protection strategies essential.

Instantel is committed to protecting the environment and designs products with longevity in mind to minimize waste. We prioritize sustainable packaging and work to ensure our equipment is safe for the environment throughout its lifecycle.  With Instantel’s monitoring solutions, you can accurately record and track overpressure levels generated by construction activities both underwater and above. Because recorded data is available almost immediately, crews can make real-time adjustments to ensure overpressure levels remain within regulatory limits. Warnings and alarms can be configured using preset trigger thresholds—customizable for each specific project—and notifications can be sent to any internet-connected device. For on-site awareness, equipment can also be paired with audible or visual alarms, helping teams respond proactively before a trigger level is exceeded.  

The effects of underwater and near-water construction activities can lead to long-term environmental impacts, and local, state, and federal regulations strictly govern the levels of overpressure that can be generated. The Instantel Minimate Pro monitoring unit is designed to help meet these requirements by accurately recording overpressure data using a hydrophone. Instantel’s hydrophone is encased in durable, waterproof, high-impact polyurethane and is built for depths up to 250 feet. It measures frequencies from 8 to 500 Hz and detects pressure changes up to 47 psi. Since underwater overpressure events are often higher in frequency but short in duration, recording at high sample rates is essential to avoid missing critical peaks. The Minimate Pro supports sample rates up to 65 kHz, providing the high-resolution data needed for precise analysis.  

Installation is simple: connect the hydrophone to a Minimate Pro data logger and submerge the hydrophone in the water. The hydrophone captures an ambient pressure reading and then records any deviations from that value as overpressure events occur. Two models are available—the Minimate Pro4 and the Minimate Pro6—offering four and six channels, respectively. This allows users to connect multiple hydrophones to monitor several locations simultaneously, with all data synchronized through one device. If one hydrophone is triggered by an exceedance, the others will simultaneously capture overpressure activity at their respective positions, giving a comprehensive picture of underwater impacts.

Instantel monitoring equipment is engineered for durability and long-term deployment, making it suitable for both short- and long-term installations. Data captured by the system is transmitted in real time and accessed through the THOR Advanced desktop platform.  With integrated Auto Call Home technology, monitoring units connected to a modem can automatically send event data to your computer for immediate analysis. 

THOR Advanced analysis tools allow you to convert waveforms into third-octave bands, apply frequency filters, and add markers to identify precise timings or frequencies—features that are retained in generated PDF reports. Its project management capabilities also make it easy to organize event data by project and configure automated email notifications for warnings or alarms.  Instantel’s underwater monitoring solutions are simple to configure and deploy. The Minimate Pro series is fully scalable—if you require a hydrophone for underwater overpressure monitoring today but need to monitor ground vibrations tomorrow, you can simply swap the hydrophone for a triaxial geophone. Built rugged and water-resistant, the Minimate Pro is designed to perform reliably in demanding environments and withstand the toughest jobsite conditions.