“Can you move fifteen containers next week?” is a question with a real answer, and it is not simply a matter of whether a carrier has fifteen trucks. Drayage capacity is governed by turn time, appointment supply, chassis availability, and — more often than anyone admits — the receiving dock at the other end. This is how to think about drayage capacity honestly, whether you are planning a peak season or evaluating a carrier’s claims.

The unit that matters is turns, not trucks

A truck does not move one container a day by nature. It moves as many as the day allows. That number, the turns per truck per day, is the real capacity variable.

In South Florida the drive legs are short — port to warehouse corridor is a modest distance. In theory that supports multiple turns. In practice the terminal side eats the day: gate queues, appointment windows that do not cluster conveniently, and empty return trips that consume a second visit.

The practical implication: adding trucks increases capacity linearly, but improving turn time increases capacity for free. A fleet that gets from one and a half turns to two turns per day gains a third more capacity without a single additional truck.

The four constraints that actually bind

1. Terminal appointment supply

This is the dominant constraint in South Florida right now. You cannot move more containers than you can book gate slots for, regardless of fleet size. When appointments are the bottleneck, additional trucks sit idle. Our post on terminal appointments at PortMiami and Port Everglades explains the mechanics.

2. Chassis availability

Containers move on chassis, and chassis are a separate pool with separate supply. During peak periods chassis shortages cap throughput before trucks do — and chassis shortages produce flips and splits, which further degrade turn time. Compounding, in the wrong direction.

3. Your receiving capacity

The constraint shippers most consistently underestimate. If your warehouse can strip six containers a day, ordering twelve does not produce twelve delivered — it produces six delivered and six containers accruing per diem in your yard or at a terminal. Capacity planning has to be an end-to-end calculation.

4. Driver hours

Hours-of-service rules cap the day. Long gate queues consume driving-eligible hours without producing movement, which is why terminal congestion reduces effective fleet capacity even when trucks are technically available.

A simple way to estimate your realistic throughput

Rather than guessing, work through this sequence:

1. Start with appointment supply. How many slots can you realistically secure per day at your terminals? This is your ceiling.
2. Check chassis. Is the right equipment type available for your container mix, especially if you have reefers or heavy loads?
3. Check receiving. How many containers can your dock genuinely strip per day with current labor?
4. Take the minimum. Your throughput is the smallest of those three, not the average.
5. Subtract for empty returns. If empties are not being handled through duals or street turns, each container is consuming roughly two terminal visits rather than one.

Most shippers who do this exercise discover their binding constraint is their own dock, not their carrier.

How to increase capacity without adding trucks

Convert live unloads to drop-and-hook

The highest-leverage change available to most shippers. A driver who drops a container and leaves is available for another turn immediately, rather than waiting two hours at your dock. See drop and hook vs. live unload.

Chase duals and street turns

Every empty returned in the same trip as an import pickup is a terminal visit you did not spend. Our post on street turns in Miami drayage covers the highest-value version of this.

Widen delivery windows

A container that must arrive at 9am consumes a specific appointment. A container that can arrive any time Tuesday lets dispatch build an efficient route. Flexibility converts directly into throughput.

Use yard staging to decouple port and dock

When your dock capacity and your container arrivals do not match, staging containers off-dock lets the port side run at full speed while your warehouse works through them at its own pace. Yard storage is the buffer that makes the two sides independent.

Give your carrier a forecast

A carrier that knows fifteen containers are coming in week 40 can plan drivers and chassis. A carrier that finds out on Monday is scrambling. Forecast accuracy matters more than forecast precision.

What to ask a carrier about capacity

Rather than “how many trucks do you have,” ask questions that reveal real capability: How many turns per truck do you average at my terminals? How do you handle appointment booking? Do you control your own chassis? What happens during peak weeks when appointments tighten? Are you asset-based or brokering this? Our post on choosing a drayage carrier in Miami covers the wider evaluation.

Frequently asked questions

How many containers can one drayage truck move per day?

It varies with terminal congestion, appointment timing, delivery distance, and whether unloads are live or drop-and-hook. Short-haul South Florida moves with drop-and-hook support more turns per day than long-distance or live-unload work. Any carrier quoting a fixed number without asking about your delivery setup is estimating rather than calculating.

What limits drayage capacity most during peak season?

Terminal appointment availability and chassis supply, usually in that order. Both tighten precisely when volume rises, which is why peak capacity is disproportionately harder to secure than the volume increase alone would suggest.

Should I contract dedicated capacity for a busy period?

If your volume is predictable and consistent, committing volume to a carrier in advance generally secures better service during tight periods than buying on the spot market. The trade-off is commitment when volume disappoints, so it works best where forecasts are reliable.