Trucking Guide to Colorado Weigh Stations and Bypass Systems

Colorado operates a network of 10 fixed Port of Entry (POE) stations and numerous mobile enforcement units managed by the Colorado State Patrol (CSP). Unlike many states where weigh stations are solely for weight enforcement, Colorado Ports of Entry serve as primary hubs for checking permits, registration, and safety credentials. Any commercial vehicle with a Gross Vehicle Weight Rating (GVWR) or Gross Combined Weight Rating (GCWR) of 16,001 pounds or more must pull into an open station. Drivers must follow all signage on Interstates 25, 70, and 76, as well as major U.S. Highways like US-50 and US-160, where mobile scales are frequently deployed to prevent bypass attempts through secondary routes. Operating through the Rockies requires careful planning to avoid unnecessary delays and fines, which start at $75 for missing a scale and scale up based on weight violations. DispatchTool helps drivers manage these requirements by providing truck-safe routing that accounts for Port of Entry locations and high-clearance restrictions on mountain passes. The platform allows dispatchers to monitor vehicle progress in real-time, ensuring that drivers stay on designated permit routes while automating the collection of IFTA data for miles driven within Colorado borders. To streamline your fleet operations and compliance, create a DispatchTool account to access integrated route planning tools.

Fixed Port of Entry Locations and Operations

The Colorado Department of Revenue, through the Colorado State Patrol, manages fixed stations at strategic border and interior points. Major facilities include the Fort Collins Port on I-25 (Northbound/Southbound), the Monument Port on I-25 (Milepost 159), and the Loma Port on I-70 near the Utah border. The Dumont station on I-70 (Milepost 233) is a critical checkpoint for mountain transit. These stations typically operate 24/7, though smaller locations like those in Lamar or Cortez may have varying hours based on seasonal traffic. Drivers should note that Colorado law C.R.S. 42-8-105 requires all commercial vehicles, including empty ones over 16,000 lbs, to stop unless they receive a bypass signal from a transponder or electronic signage.

Electronic Bypass Systems and PrePass

Colorado utilizes the PrePass system and Drivewyze to facilitate bypasses for carriers with high safety scores. According to the Colorado State Patrol, roughly 75% of qualified trucks are eligible for bypass at equipped stations. To qualify, carriers must maintain an Inspection Selection System (ISS) score below 75. A score between 75 and 100 results in a mandatory pull-in for inspection. The PrePass system in Colorado also integrates with weigh-in-motion (WIM) sensors located approximately 750 to 1,000 feet before the station. If the WIM sensors detect an overweight condition or an axle imbalance, the transponder will signal a red light, requiring the driver to enter the static scales regardless of their safety rating.

Colorado Weight Limits and Oversize Permits

Legal weight limits in Colorado follow the Federal Bridge Formula, capped at 80,000 pounds for a standard five-axle combination. Single axles are limited to 20,000 pounds, and tandem axles are limited to 34,000 pounds. For specialized loads, CDOT issues LCV (Long Combination Vehicle) permits for Rocky Mountain Doubles (up to 110,000 lbs) and Turnpike Doubles (up to 110,000 lbs) on designated routes. Overweight fines are strictly enforced under C.R.S. 42-4-510. For example, a load that is 1,001 to 2,000 pounds overweight faces a $100 fine, while loads exceeding 10,000 pounds over legal limits can face fines exceeding $1,000 plus additional per-pound penalties.

Chain Laws and Winter Enforcement

Weigh stations often serve as the primary enforcement points for the Colorado Chain Law (Code 15). From September 1 to May 31, all commercial vehicles traveling on I-70 between Milepost 133 (Dotsero) and Milepost 259 (Morrison) must carry sufficient tire chains. Failure to carry chains results in a $50 fine plus a $17 surcharge. If a driver fails to install chains when the law is in effect and subsequently blocks the highway, the fine increases to $500 plus a $157 surcharge. Ports of Entry will frequently inspect tire tread depth and the presence of chains during these months to ensure mountain safety.

Mobile Enforcement and Roving Patrols

The Colorado State Patrol Motor Carrier Safety Section operates mobile scales and portable inspection units to cover gaps between fixed ports. These units focus on high-crash corridors and secondary highways like US-285 and US-550. Mobile units have the same authority as fixed ports to conduct Level I, II, or III North American Standard Inspections. In 2023, the CSP conducted over 30,000 commercial vehicle inspections. Drivers found attempting to bypass a fixed port by taking a secondary route can be cited for 'Avoiding a Port of Entry,' a misdemeanor that carries higher penalties than a simple failure-to-stop violation.

Reporting and Documentation Requirements

Upon entering a Colorado Port of Entry, drivers must have their Electronic Logging Device (ELD) records, IFTA credentials, and registration ready for inspection. Colorado is a member of the International Registration Plan (IRP), and vehicles not registered under IRP must purchase a trip permit. A 72-hour permit for trip and fuel costs approximately $7.00 for the permit plus the current fuel tax rate. The CSP uses the Commercial Vehicle Information Systems and Networks (CVISN) to instantly verify carrier authority and insurance status. Ensuring your paperwork is digitized and accessible can reduce inspection time from 20 minutes down to less than 5 minutes for routine stops.

Sources

Colorado State Patrol - Port of Entry (2024) — https://csp.colorado.gov/sections/port-of-entry Colorado Department of Transportation - Chain Law (2024) — https://www.codot.gov/travel/commercial-vehicles/chain-law Colorado Revised Statutes C.R.S. 42-8-105 (2023) — https://leg.colorado.gov/statutes

Frequently asked

What is the weight threshold for stopping at Colorado scales?

Every commercial vehicle with a GVWR of 16,001 pounds or more is required to stop at all open Colorado Port of Entry stations.

Does Colorado use PrePass?

Yes, Colorado supports PrePass at most major Port of Entry locations, including the I-25 and I-70 corridors, allowing trucks with high safety scores to bypass scales.

How much is the fine for bypassing a weigh station in Colorado?

The minimum fine for failing to stop at an open Port of Entry is $75, but this can increase significantly if the bypass was intentional to avoid weight or safety violations.

Are empty trucks required to stop at Colorado weigh stations?

Yes, all commercial vehicles over 16,000 lbs GVWR must enter the port even if they are empty, unless they receive a green light from a bypass transponder.

Where are the most active weigh stations in Colorado?

The most active stations are the Fort Collins Port on I-25 North, the Monument Port on I-25 South, and the Loma Port on I-70 Eastbound.