Seasonal modes (river barges in summer, winter ice routes, regional air lift) require 3PLs that coordinate multimodal schedules, consolidate freight to reduce per-unit cost, and maintain visibility. Prioritize partners with barge/air carrier relationships, contingency routing, and performance SLAs tied to seasonal windows.

Look for inventory pre-positioning, cross-docking, scalable pick-and-pack, kitting, returns handling, and real-time WMS/TMS integration. These capabilities reduce expedited freight spend and improve fill rates; consider SLA commitments for cutoffs and order cycle times to match customer expectations.

Use consolidation programs, scheduled bulk shipments during navigable seasons, inventory pooling, and vendor-managed replenishment to lower per-unit transport costs. Negotiate minimums and volume tiers, and require carrier performance reporting to control dwell and expedite charges.

Plan for river freeze/thaw windows, weather-related delays, and limited daylight impacts. Account for local land-use permits, Native corporation regulations, and environmental compliance. Build contingency inventory buffers and a documented escalation plan with the 3PL for seasonal disruptions.