The Defense Advanced Research Projects Agency (DARPA) is moving to solve a persistent military logistics problem: the decrepit state of strategic port infrastructure. The agency is now soliciting proposals for autonomous systems capable of 3D printing concrete structures underwater using locally sourced seafloor sand, clay, and seawater.

Domestic Infrastructure for National Primacy

The initiative directly targets the logistical vulnerabilities of American naval power. A government watchdog report previously flagged the poor condition of strategic military seaport facilities, and a recent Coast Guard assessment found that roughly 45 percent of its maritime infrastructure, including piers and moorings, has exceeded its expected service life. This decay represents a direct threat to the United States’ ability to project force and secure supply chains, placing the burden for maintaining American primacy squarely on failing concrete.

Unlike current methods that DARPA deems too slow, costly, and logistically burdensome for expeditionary use, the proposed autonomous systems would operate in waters up to 100 meters deep. The program aims to eliminate the need for vulnerable, long-haul transport of specialized construction materials by having robotic platforms mix binding agents with native sediments. This directly serves the national interest by securing domestic military supply lines and reducing reliance on fragile foreign maritime chokepoints for port repairs.

Many maritime military facilities are already in poor condition. Current approaches are too slow, costly, and environmentally intrusive, making them unsuitable for expeditionary or military operations, DARPA stated in its call for solutions.

Technology and Economic Application

The requested technology would use artificial intelligence to determine the optimal local sediment mix for building and repairing seawalls, artificial reefs, and providing blowout protection for underwater pipelines, in addition to port facilities. This is a parallel track to other DARPA-funded research examining self-healing concrete inspired by human vascular systems. The ultimate goal is a fully autonomous, deepwater-capable system that strengthens America's economic and military footing without requiring protracted negotiations with unstable foreign governments for base access—serving the interests of American workers and warfighters tasked with maintaining global maritime stability.