Vessels Are Within 0.54 Miles of Each Other at Anchor 53% of the Time. That Is a Berth-Queue Story for Secondary-Port Industrial.

If you underwrite industrial real estate at secondary US ports — Savannah, Charleston, Wilmington NC, Tacoma — the rate at which vessels collide-close at anchor is the leading indicator your underwriting model is missing.

The Setup

Out of 16,260 close-quarter encounters logged at anchorage globally over the last 30 days, the stand-on vessel had to maneuver in 8,619 of them (53.0%), and 8,121 (49.9%) escalated into formal Rule 17(b) handoffs. The vessels averaged just 0.54 nautical miles minimum range and 0.22 nm minimum closest-point-of-approach — distances measured in feet, not miles, between hulls of ~250m each.

Translation: vessels at anchor are routinely closer to each other than the length of the ship they are anchored next to. That is not "anchorage demand." That is berth-queue overflow.

The Chain

The anchorage-deviation rate is upstream of every operational lever a 3PL or industrial landlord touches. A vessel waiting at anchor is a vessel not unloading. A vessel not unloading is a vessel whose cargo is not transiting through the terminal-adjacent intermodal yard. A 3PL that needs that cargo on a specific arrival window has two responses: hold more buffer inventory at a forward warehouse, or route through a less-congested port. Both responses anchor industrial CRE demand at submarkets near the secondary ports — the ones that benefit when the primary is queued.

The published Locus posts on Inland Empire warehouse demand and Houston Ship Channel bonded storage have already covered the primary-port crossover. This is the next-order signal: when anchorage congestion is high enough that vessels are routinely within hundreds of meters of each other for hours, the marginal box of cargo gets routed somewhere else. Somewhere else is increasingly Savannah, Charleston, Wilmington (NC), and Tacoma — the four secondary US container ports that absorbed the biggest share of post-2022 routing diversion.

The Implication

The 53% anchorage deviation rate is a calibration point for industrial REITs underwriting at secondary ports. If anchorage congestion at primary ports stays at this level for two consecutive quarters, expect a step-function in 3PL leasing demand at secondary-port industrial submarkets, not a linear one. Tenants do not move incrementally — they move when the buffer-inventory math crosses an internal threshold, and that threshold is set by service-level agreements with retail and industrial customers, not by spot freight rates.

For a portfolio-level read, the directional call is: secondary-port industrial cap rates that compressed during the 2023–2024 "diversification trade" are not in fact rich. They are priced to a normal-distribution model of port congestion. The actual distribution is fat-tailed, and the tail is showing up in the anchorage encounter data.

What to Watch

• CBRE/JLL Q2 2026 secondary-port industrial vacancy reports. A drop below 4% in Savannah or Charleston flex-warehouse vacancy is the lagging confirmation of this leading indicator.
• Asking-rent spreads between Savannah and Atlanta industrial. If the spread compresses (Savannah getting bid up relative to Atlanta), the routing diversion is real.
• Carrier blank-sailing schedules into LA/LB and NY/NJ. Blank sailings at primary ports almost always presage box-volume gains at secondary ports four to eight weeks later.
• Anchorage encounter rates over the next 30 days. A drop from 53% deviation toward 45% would suggest the queue is clearing — a continued run >50% says it is not.

Limitations

The anchorage encounter signal is global, not US-specific. The published rate aggregates across all anchorages worldwide, and individual US ports may run higher or lower than that mean. Linking the global signal to a specific US secondary port still requires port-level dwell-time and waiting-list data, which the next iteration of the Overwatch pipeline (port_dwell_distribution materialized view, AXO-134 family) will close. Industrial CRE demand at secondary ports is also driven by tenant-specific decisions that take quarters to lag the operational signal — a buyer treating this as a six-week trading thesis will be disappointed; a 12–24 month thesis is correctly sized.

Data current as of 2026-05-01. Sources: pairwise_encounter (AXO-117 pipeline), 30-day anchorage cohort. Crossover analysis: Axiom Locus, port-adjacent industrial signal pack.