DHS Plans $100M+ Border Tunnel Detection Contract

The Department of Homeland Security has announced plans for a contract exceeding $100 million to expand the Persistent Surveillance and Detection (PSD) system under the Cross Border Tunnel Threat (CBTT) programme, managed by US Customs and Border Protection.

The firm-fixed-price contract targets subsurface perimeter threats — tunnels constructed beneath the US-Mexico border for smuggling and trafficking. Solicitation release was anticipated for November 10, 2025, with contract award expected in Q1 FY2026.

Tunnel detection represents the most technically demanding application in perimeter security. Unlike surface-level intrusion detection, where multiple mature sensor technologies (fence sensors, radar, thermal cameras, DAS) provide reliable detection, subsurface monitoring requires geophysical sensing techniques — seismic arrays, ground-penetrating radar, and distributed fiber optic sensors tuned to detect digging activity at depth.

The CBTT programme has operated along the southwest border since the mid-2000s, with tunnel discoveries averaging several per year in the San Diego and Nogales sectors. The $100M+ expansion signals that DHS considers the subsurface threat sufficient to justify significant capital investment in detection infrastructure — investment that also drives technology development applicable to other subsurface perimeter scenarios (utility vault protection, underground facility security, mining perimeter monitoring).

For the perimeter detection industry, the CBTT contract represents a specialised but technically prestigious procurement. Vendors with proven subsurface sensing capabilities — particularly fiber optic DAS companies with seismic detection algorithms — are positioned to compete.