An underground delivery train comes to the Atlanta suburbs
A pilot project in an Atlanta suburb is testing an underground delivery system: small autonomous carts running through 18-inch pipes to move food and parcels between a shopping center and an office park. Commenters weigh the appeal of fast, traffic-free deliveries against the huge capital costs of tunneling, complex maintenance and rescue scenarios, and questions about whether such infrastructure can ever be economically viable compared to bikes, sidewalk robots, or better urban planning. Many note historical precedents like pneumatic mail tubes and cargo tunnels, arguing that while the idea is technically plausible, its success will hinge on density, governance, and long-term operating costs.
Concept and Inspiration
- System is an underground 18-inch pipe with small battery-powered autonomous carts shuttling packages and food (“hyperloop for lunch,” “mini rubber-tyre metro”).
- Explicitly compared to pneumatic tubes, Factorio-style belts, and humorous “burrito tunnel” concepts.
- Current pilot is a single point-to-point line (shopping center ↔ office park), with lockers and a crane-like interface.
Operations and Reliability
- Concern about what happens when a vehicle gets stuck: suggestions include backing vehicles out, using dedicated rescue/tow carts, walkable tunnels, or even a “powerful plunger.”
- Debate over reliability: some argue electric carts tolerate imperfect pipes better than pneumatic capsules; others note far more failure points in a BEV than in a simple tube canister.
- Issues raised around sabotage or accidental blockage (spray foam, airbags, oil, trash) and how to clear it.
Economics and Scalability
- Trenching and directional boring cited as extremely expensive ($75–100+ per foot for similar piping).
- Skeptics doubt last-mile economics versus a cheap human on an e-bike using subsidized roads, or cargo bikes in protected lanes.
- Questions about break-even time, whether enough volume exists (e.g., “a lot of Big Macs”), and unclear network design beyond simple point-to-point.
- Concerns that abandoned pipes worsen already-poor underground documentation, raising costs for future work.
Alternatives and Urban Planning
- Competing ideas: sidewalk robots, bikes/e-bikes, golf carts, loop buses, better postal service, cargo drones, and simply building sidewalks or protected bike lanes.
- Some argue it addresses a land-use problem (office parks too far from restaurants) better solved by denser, mixed-use development; others say that’s a decades-long, politically unlikely fix, so incremental tech is appealing.
- Climate and comfort (Atlanta heat/humidity) cited as barriers to walking/biking for office workers.
Security and Misuse
- System could be used to transport dangerous items (flammables, bombs), not just burritos and packages.
- Screening, containment, and failure modes underwater or underground are seen as nontrivial.
Historical and Parallel Systems
- Comparisons to historic pneumatic mail systems (New York, Paris) and London’s Post Office Railway, plus modern hospital/store tubes and Swiss cargo-tunnel proposals.
- Some enthusiasm that, if economics can be made to work, this could become utility-like infrastructure; others label it “gadgetbahn” and a likely VC money sink.
Overall Sentiment
- Thread mixes genuine excitement about an old sci-fi idea finally being piloted with substantial skepticism about cost, reliability, scalability, and whether it solves the right problem.