How does CBP report and map detection technology miles compared with physical barrier miles?
Executive summary
Customs and Border Protection reports and illustrates "detection technology miles" and "physical barrier miles" as distinct but complementary layers on its Smart Wall map and in contract announcements: the map labels stretches as barrier built/planned/under-construction versus stretches designated to be covered by detection technology, and CBP pairs contract tallies (miles of wall awarded) with separate tallies for technology deployments (miles of sensors/cameras) [1] [2]. Advocates and critics point out that the agency bundles disparate systems under the "Smart Wall" umbrella—so a mile of “technology” is not the same physical footprint or operational effect as a mile of steel bollard wall [3] [4].
1. How CBP draws the line on the map
CBP’s interactive Smart Wall map separates locations by project status—Planned, Awarded, and Under Construction—and marks where steel bollard or waterborne barriers will be sited versus where detection technology will be used because terrain or remoteness makes a barrier impractical; the agency states approximately 536 miles of the U.S.–Mexico border without barrier will be covered by detection technology [1]. The map therefore communicates category and status rather than equating a technology-mile with a contiguous physical barrier mile, a distinction CBP reiterates in its FAQ that the Smart Wall combines barriers with lights, cameras and other detection assets [3].
2. What CBP reports in contract and program tallies
When announcing OBBB contract awards, DHS/CBP report separate numerical tallies: the 2025 announcements cited roughly 230 miles of new barriers alongside nearly 400 miles of new detection technology in aggregate contract language, and smaller regional project notices list miles of primary and secondary wall as well as separate mileage for "detection technology" [2] [5]. Local project notices follow the same pattern—Southern Arizona filings, for example, mentioned 19 miles of new primary wall, 19 miles of secondary wall and 136 miles of detection technology in the same package [5] [4].
3. What a “technology mile” actually means in practice
CBP’s public descriptions and technical documents show that “technology” encompasses movable and fixed sensors and cameras, surveillance towers with multi-mile coverage, radar, aerostats and other sensing layers rather than a continuous physical obstruction; a 33‑foot tower is described as “seeing” an area roughly three miles in diameter, illustrating how one tower can cover several miles of linear border without a one-to-one physical extension like a wall panel [6] [7]. IEEE and DHS materials underscore that detection systems are heterogeneous—ground sensors, radars and cameras have differing ranges and maintenance needs—so a reported mile of detection coverage is a programmatic construct, not a single contiguous physical object [8] [7].
4. Limits in comparability and effectiveness metrics
Independent reporting and oversight have flagged that CBP lacks a rigorous, public metric to equate or validate the operational equivalence of a mile of technology to a mile of barrier; past programs called “smart” produced mixed results and GAO-style critiques have noted CBP does not consistently publish clear measures of effectiveness for surveillance data, a point underscored by retrospective reporting on earlier virtual fence efforts [9]. CBP’s internal framing—that barriers are “most effective” when combined with technology—signals an assertion of complementarity rather than equivalence, but does not resolve how miles should be compared analytically [3].
5. Political framing, environmental pushback, and transparency stakes
CBP and the administration frame the Smart Wall as delivering “more miles of barriers, more technology, and more capability,” language used in contract releases to justify large appropriations, while environmental groups and local critics emphasize ecological, cultural and procedural harms tied to new barrier miles and to the spread of lighting and sensors across landscapes—criticisms lodged during public-comment periods on region-specific projects [2] [4]. The map and contract tallies serve both as program accounting and as political messaging; transparency debates focus on whether mileage figures obscure qualitative differences between detection coverage and a steel wall’s physical impediment [2] [4].
6. Bottom line
CBP reports and maps detection-technology miles separately from physical barrier miles, using categorical map labels and distinct contract tallies to communicate planned coverage, but agency materials and external reporting make clear that a “mile” of technology is a programmatic unit representing varied sensor types and coverage footprints rather than a direct physical analog to a mile of steel bollard wall, and public oversight documents raise questions about how those different miles should be compared for effectiveness or environmental impact [1] [2] [6] [9].