U.S. rail intermodal growth slowed sharply in the latest weekly data, signaling that some Class I railroads are straining to sustain peak-season volumes.
The Association of American Railroads (AAR) reported that total U.S. rail traffic for the week ending July 11, 2026, reached 503,525 carloads and intermodal units, up 1.5% from the same week last year. Carload freight slipped 0.4% to 223,040 carloads, while intermodal traffic — containers and trailers — rose 3% year-over-year to 280,485 units. That 3% gain is a marked deceleration from the 12.9% surge recorded the prior week, according to AAR data.
Context: Peak-season pressure on rail networks
The slowdown comes amid a record June for container imports, which has left containers waiting an average of five days for rail transit out of the Port of Los Angeles — about a day longer than normal, the AAR reported. The port is the primary gateway for Asian goods entering the U.S., and rail delays there ripple across the national intermodal network.
Online drayage platform Drayage.com saw demand in Chicago hit an all-time high for the year: 3,618 unique clicks in a single day on Wednesday, up from an average of 2,500 per day, according to a LinkedIn post by President Jason Hilsenbeck. “If you are trying to find drayage coverage in Chicago,” he wrote, “[you’ll] need to pay a higher rate.”
Traffic by commodity and cumulative volumes
Grain led the commodities with year-over-year gains for the eighth consecutive month. It was followed by petroleum and related products (up 7.4%) and metallic ores and metals (up 6.7%). Forest products, which have struggled against a difficult housing market, pulled even with last year, falling just 0.03%. Housing inventory is higher, and asking rents and list prices are softening, according to several trackers cited by the AAR.
Through week 27 (the first 27 weeks of 2026), cumulative volumes were:
| Metric | Volume | Year-over-year change |
|---|---|---|
| Carloads | 6,117,342 | +3.1% |
| Intermodal units | 7,534,897 | +3.6% |
| Combined total | 13,652,239 | +3.4% |
On North American railroads (nine reporting U.S., Canadian, and Mexican carriers), the week's total traffic rose 2.3% year-over-year to 695,079 carloads and intermodal units. Year-to-date, North American volume gained 2.9% to 18,792,861 units.
What this means for shippers and logistics operators
For freight forwarders and 3PLs, the slowing intermodal growth suggests that the peak-season surge may be hitting capacity ceilings. The extended rail dwell time at the Port of Los Angeles — five days vs. four days normal — raises the risk of missed delivery windows and higher detention costs.
Drayage availability in Chicago is tightening, and rates are expected to rise as carriers and brokers compete for limited capacity. Shippers using intermodal for transcontinental moves should prepare for potential delays and consider alternative routing or earlier booking windows.
Watch list
- Rail dwell times at the Port of Los Angeles and other West Coast gateways over the next two weeks; if they exceed five days, congestion could spill into September peak.
- Drayage rates in Chicago and other major intermodal hubs; sustained high demand could trigger general rate increases.
- Weekly AAR carload and intermodal data for signs of further deceleration; the 3% intermodal growth rate could slip below 2% if chassis and railcar availability worsen.
- Housing market data: forest products volumes may recover if mortgage rates ease and new construction picks up.
- Upcoming peak season import volumes: if July imports match June's record, rail capacity constraints could intensify.
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