Marine Dredging Insurance and Microplastic Liabilities: Are Your Clients Covered?

Marine dredging operations have long played a vital role in navigation, port maintenance, and environmental restoration. But as awareness of microplastic pollution grows, so does scrutiny over the environmental risks that dredging may unintentionally exacerbate. These operations may disturb and redistribute microplastics embedded in marine sediments — potentially releasing them into surrounding waters or sensitive habitats.

For insurance agents representing marine contractors, this issue raises a critical question: Does marine dredging insurance provide adequate protection for the environmental liabilities that come with disturbing microplastic-contaminated sediments? Marine dredging insurance traditionally focuses on operational risks like property damage and turbidity control. Today, it must also account for emerging pollution exposures, including the disturbance of microplastics.

How Dredging Interacts With Microplastic Pollution

Research shows that microplastics tend to accumulate in sediments across ports, harbors, and estuaries — areas that are commonly dredged for commercial and maintenance purposes. When sediment is mechanically disturbed, these particles can be resuspended into the water column, transported by currents, or redeposited into previously uncontaminated zones.

This unintended redistribution doesn’t just pose ecological risks. It could expose dredging contractors to regulatory scrutiny, cleanup demands, or third-party liability if microplastics contribute to downstream pollution or habitat degradation. 

What Standard Policies Typically Address

Marine dredging insurance policies generally include coverage for:

• Equipment and property damage
• Third-party bodily injury and property damage
• General and marine liability
• Contractors pollution liability (CPL) for sudden and accidental releases

These policies are designed to address common operational risks, such as fuel spills, hydraulic fluid leaks, or sediment discharges. However, they often rely on specific definitions of “pollutants” or “contaminants” and may exclude long-term or known environmental conditions.

If microplastic resuspension isn’t classified as a covered pollutant or considered accidental under policy definitions, insurers could challenge claims or deny coverage outright. Policy interpretation often depends on language specificity and insurer precedent.

Gaps and Gray Areas: What Agents Should Watch For

The liabilities associated with microplastic disturbance often fall into coverage gray zones, especially if the policy:

• Excludes gradual or non-sudden pollution
• Limits coverage to specific, named pollutants
• Has a known conditions exclusion (e.g., if the contractor is aware of contamination in the dredging zone)
• Requires regulatory “triggers” to activate cleanup or third-party liability terms

Moreover, microplastics are rarely referenced by name in most policies, making it unclear whether they’re even covered under existing pollution liability language.

Why Specialized Underwriting Is Crucial

Dredging contractors working in busy or industrial waterways often encounter microplastics and other legacy contaminants in their work. Yet there’s often no clear regulatory or technical guidance on how to detect or manage microplastics during sediment removal — nor is there clear regulatory guidance. For example, the United States currently lacks formal regulatory standards for addressing microplastics in dredged sediment.

These complex and evolving environmental risks make it essential to partner with an experienced managing general agent like Merrimac Marine Insurance. Our underwriters understand the operational and environmental nuances of marine work, and we help agents design programs that reflect site-specific risks and regulatory realities.

From reviewing navigation zones to defining pollutants, we work closely with agents to ensure clarity around what’s covered and what isn’t.

Preparing Clients for a Changing Environmental Landscape

As environmental expectations rise and microplastic research expands, marine contractors may increasingly be held accountable not just for what they remove but also for what they disturb. Insurance agents need to anticipate this shift by helping clients assess their risk exposure and reevaluate their policies.

Marine dredging insurance must evolve alongside the science and regulations guiding today’s marine construction and maintenance work. It all begins with asking the right questions — and choosing the right partners.

Want help aligning dredging insurance with modern environmental risks? Contact Merrimac Marine Insurance today.

About Merrimac Marine Insurance

At Merrimac Marine, we are dedicated to providing insurance for the marine industry to protect your clients’ businesses and assets. For more information about our products and programs, contact our specialists today at (800) 681-1998.