BOEM Offshore Wind Approvals: Radar Risks Identified, Not Resolved

From MasterResource

By Lisa Linowes

“Congress now has an opportunity—and an obligation—to correct this flawed process by requiring rigorous, upfront, full-footprint review of radar impacts on air safety and national security before any further offshore wind projects proceed to construction or operation.”

The Biden administration positioned large-scale offshore wind development as the centerpiece of its national decarbonization strategy. Under this mandate, the Bureau of Ocean Energy Management (BOEM) conducted extensive multi-agency reviews, examining impacts on marine ecology, commercial fishing, and cultural resources. In rapid succession, it issued Findings of No Significant Impact and greenlit thirteen massive projects from Massachusetts to Virginia. 

However, one critical risk category—radar interference—presents direct and unresolved implications for civilian air safety and national security.

1. The Technical Reality: A Problem Without a “Silver Bullet”

Offshore wind turbines create a documented technical hazard: the massive rotating blades generate Doppler returns that primary radar systems often misinterpret as real targets. The result is degraded detection capability, false targets, clutter, and, in some cases, gaps in coverage.

While the wind industry maintains these impacts are manageable through software-based mitigation tools, the Department of Energy’s Wind Turbine Radar Interference Mitigation (WTRIM) reports suggest otherwise. Testing of available technologies concluded they “did not significantly improve surveillance capability.” Benjamin Karlson of Sandia National Laboratories, who led years of testing, stated bluntly: “There’s no silver bullet.” 

Furthermore, the WTRIM working group informed Congress in 2023 that, despite progress on some radar types, the addition of offshore and weather radar systems to its responsibilities has pushed the timeline for meeting safety objectives to 2035, effectively acknowledging the problem remains unsolved more than two decades after it was first identified.

2. Geopolitical Precedent: The International Response

While the U.S. has accelerated deployment, other global powers reached a starkly different conclusion: governments have prioritized national security considerations in evaluating offshore wind development.

From our closest European allies to our strategic competitors, the consensus is the same. In November 2024, Sweden flatly rejected 13 offshore wind projects, warning that turbines would slash missile detection times from two minutes to a mere 60 seconds. Finland has blocked over 200 projects for similar reasons, and the United Kingdom is spending £1.5 billion to replace its entire radar network. Even China has restricted development in the Fujian province to protect its military surveillance opposite Taiwan.

The common thread is clear: radar interference is not a minor glitch; it is a system-level vulnerability.

3. The Regulatory Gap: A Flawed U.S. Process

By contrast, BOEM approved these projects through a framework that never required a complete, system-level determination of radar impacts. That framework rested on three structural flaws:

Narrow DoD Focus

The Department of Defense (DoD) Siting Clearinghouse reviewed and cleared projects based strictly on impacts to military-specific assets and readiness. This process did not—and was not designed to—account for the broader shared radar networks that support civilian air traffic control (ATC) and homeland security missions.

The 12-Nautical-Mile Void

The Federal Aviation Administration (FAA) oversees civilian air safety within U.S. territorial waters (12 NM from shore). Of the roughly 460 turbines operational or under construction on the East Coast, fewer than 30 underwent full FAA determination. BOEM had the authority to require FAA reviews of entire project footprints yet chose not to bridge the 12 NM gap. Instead, for the hundreds of turbines beyond that boundary, BOEM expected developers to coordinate with aviation interests and conduct their own studies as part of standard due diligence.

In practice, what developers delivered were preliminary screenings, not detailed studies. The Revolution Wind and Vineyard Wind reports both found radar impacts were “highly likely,” yet both explicitly stated that their analyses were “preliminary,” “cursory,” and “do not provide an official decision as to whether impacts are acceptable.” Rather than rejecting the incomplete findings, BOEM accepted them as the basis for project approval.

Deferred and Limited Mitigation 

Mitigation efforts were confined to standardized agreements between project proponents and DoD. Key testing and validation of even these limited measures were tied to project commissioning—occurring near or after full build-out. Because these large projects are built in phases, meaningful validation may not occur until years after BOEM granted initial approval. 

Offshore wind was treated as a priority to be accelerated at scale. Risks to radar and surveillance systems were not ignored—but they were framed as technical challenges to be managed rather than issues that had to be settled upfront. This approach turned potential safety and security risks into an afterthought. 

4. The Predictable Consequences

By accepting those incomplete analyses and deferring validation until turbines were already operating, BOEM made a de facto determination that the risks were acceptable. This reliance on unproven evidence produced a thin administrative record—one that declared impacts “addressed” while narrowing future federal action.

When the Trump administration attempted to suspend construction over radar concerns, the courts were constrained by BOEM’s prior approvals and the administrative record that had already treated the risks as addressed. Judges found insufficient basis to support a reversal. While agencies can change course, they must justify it—and BOEM’s process had not produced the evidence needed to support that shift. Faced with a thin safety record versus immediate financial harm to developers, the courts allowed construction to proceed.

Once billions were committed and turbines began rising, reversal became nearly impossible. 

5. The Resulting Reality: A Degraded Radar Environment

BOEM approved the projects without ever requiring—or conducting—a definitive determination of acceptable radar degradation.

Without a clear finding of acceptable risk, the system did not eliminate the problem—it absorbed it. The changes to America’s coastal radar environment are now permanent. 

This degradation poses direct safety risks to aviation, including degraded ATC performance, increased clutter and false targets, compressed low-altitude airspace, and heightened collision hazards for low-flying aircraft, including general aviation, helicopters, and search-and-rescue operations.

Modern threats — low-altitude cruise missiles, unmanned aerial systems, and drone swarms — are designed to exploit exactly these gaps in coverage and tracking. Sweden’s decision shows that even modest degradation can materially reduce reaction time. The United States never made a comparable finding before allowing widespread deployment.

Congress now has an opportunity—and an obligation—to correct this flawed process by requiring rigorous, upfront, full-footprint review of radar impacts on air safety and national security before any further offshore wind projects proceed to construction or operation.

The government must decide whether the risk is acceptable before infrastructure is built—not after.