Intermodal motor carriers face unique billing complexity when containers move on chassis belonging to equipment providers such as DCLI, TRAC Intermodal, and Flexi-Van. Split returns, pool transfers, and daily per-diem charges create a reconciliation environment that most TMS platforms only partially address. This technical architecture details the database schema, ETL processes, and business rules required to automate chassis split billing, IEP pool auditing, and accurate UIIA per-diem cost allocation.
The Operational Challenge
When a driver returns an ocean container to a terminal using a chassis from a different IEP pool than the one on which the container was picked up, three separate billing events must occur simultaneously:
- The original pool provider must be billed for the full per-diem period.
- The replacement pool provider must receive credit or a transfer transaction.
- The per-diem cost must be correctly allocated to the responsible load, customer, or internal cost center for driver settlement and freight billing.
Without an integrated architecture, these transactions are handled manually, resulting in per-diem leakage, disputed invoices, and settlement errors that affect both carrier profitability and driver pay accuracy.
Core Data Model
The solution centers on a set of normalized SQL Server tables that exist alongside your primary TMS (Truckmate, McLeod, or TMW). Key entities include:
- ChassisMaster - Current pool ownership, UIIA agreement ID, daily rate schedule, and GPS/telematics device ID.
- ChassisTransactionLog - Every out-gate and in-gate event with terminal, timestamp, container number, and driver.
- PoolReconciliationSnapshot - Daily import of each IEP's official pool inventory and activity report.
- SplitBillingEvent - Detected mismatches with calculated per-diem amounts, supporting documents, and dispute status.
- PerDiemAllocation - Final cost distribution to load, shipment, or driver settlement line.
| Provider | Daily Rate | Free Days (Typical) | Grace Period | Dispute Window |
|---|---|---|---|---|
| DCLI | $28.50 | 2 | 24 hrs | 45 days |
| TRAC | $31.75 | 3 | 48 hrs | 30 days |
| Flexi-Van | $26.00 | 2 | 24 hrs | 60 days |
| Own/leased chassis | $0.00 | N/A | N/A | N/A |
Automated Reconciliation Engine
A nightly SQL Server Integration Services (SSIS) or Azure Data Factory pipeline performs the following steps:
- Import EDI 214 status updates and TMS gate events into ChassisTransactionLog.
- Import each IEP pool activity report (usually CSV or Excel) into PoolReconciliationSnapshot.
- Execute a stored procedure that identifies split returns by joining on container number and chassis serial where pool ownership differs between out-gate and in-gate.
- Calculate per-diem days using business rules that respect free time, weekends, holidays, and terminal-specific grace periods.
- Generate outbound dispute or billing files in the format required by each IEP (typically 997/999 acknowledgments or custom Excel templates).
- Allocate final per-diem cost to the corresponding load using rules that can incorporate fuel surcharges, detention, and driver settlement logic already present in your McLeod or Truckmate system.
Telematics Integration Layer
Modern chassis pools increasingly require GPS-based proof of location for per-diem disputes. The architecture includes an ELD/Telematics API integration service that captures chassis location at the moment of terminal gate transactions. This data is stored in the ChassisTransactionLog and automatically attached to dispute packages. The same service can feed HOS, IFTA mileage, and driver settlement calculations, creating a single source of truth for both operational and financial systems.
Financial and Settlement Integration
Per-diem costs flow into your transportation accounting integration through a dedicated cost-allocation interface. This ensures that customer freight invoices (EDI 210) accurately reflect accessorial charges and that driver settlements include the correct deduction or reimbursement for chassis usage. When using TMW or McLeod, the architecture writes approved allocation records directly into the native settlement and billing tables via safe, auditable stored procedures.
Strong Tower Consulting, LLC and Exspeedite LLC are separately organized sister companies under common ownership (separate EINs). We document complete, production-ready architectures that you own. You never have to buy our software to implement the solution with your own developers or any preferred integration partner.
Implementation Roadmap
Most intermodal carriers complete the initial chassis split-billing and pool reconciliation engine in 10-12 weeks. The project typically includes:
- Requirements workshops with dispatch, billing, and maintenance teams.
- SQL schema deployment and data migration from existing spreadsheets.
- Stored procedure development for split detection and per-diem calculation.
- EDI 204/214/210 transaction mapping updates where required.
- User training and exception workflow configuration.
- Go-live support and 30-day hypercare.
Carriers who implement this architecture typically recover between 12% and 18% of previously lost chassis per-diem revenue while reducing administrative labor by approximately 65%.
Related Practices
This architecture is often implemented together with broader TMS implementation, ELD and EDI integration, transportation accounting integration, and SQL data mining initiatives.
Related Guides
See also our Intermodal Drayage Terminal Demurrage and Per Diem Mitigation Playbook, ELD/HOS Telematics API Integration Architecture, and TMS EDI 204/990/214/210 Transaction Lifecycle Playbook.