Spring weight restrictions: Know your limits

Although consistently warm weather might still be a ways off, it’s not too soon to start thinking about spring weight restrictions. Seasonal weight restrictions may vary from one year to the next based on the weather. Typically, effective dates for spring weight restrictions are based on:

• Frost depths measured along state highways,
• Observed road conditions, and
• Weather forecasts.

When the frost line is deep enough to allow moisture to escape and a state or province feels its roads have regained stability, weight restrictions will be removed.

Different road types have different limits

Interstates and state highways have their own weight limits. Weight limits on local and secondary roads may potentially have stricter limits than primary highways. The design of the road will determine how soon the road can return to regular weight limits.

• Primary roadways — Interstates and major highways generally have thick, well-graded foundations so they recover more quickly. The final surface is often reinforced concrete, which remains strong and secure regardless of the season.
• Secondary roadways — The foundations of these roads aren’t as heavy or thick as those of primary roads, so it takes longer for them to return to regular weight limits. Secondary roads are often topped with asphalt, which is not as rigid as concrete. The combination of wet conditions and softer foundations makes the roadways unable to support as much weight as they can during a dry summer or frozen winter.

States and provinces have their own restrictions

While weight restrictions are more prevalent in the northern half of the U.S. and into Canada, any state or province can impose restrictions.

When enforcing spring weight restrictions, state law enforcement will sometimes use portable scales on secondary roads. The portable scales aren’t meant to “catch” drivers but are there to remind them of the importance of following spring weight restrictions.

Why are weight restrictions enforced?

Highway infrastructure funds are hard to generate, and states simply can’t afford the expenses of repairing or replacing roadways due to heavy loads during the spring.

Monitoring limits

Motor carriers and their drivers can monitor state and province websites for affected highways and the effective dates of spring weight restrictions. Signing up for automatic email or text alerts from the states and provinces is another way to stay up to date.

Spring weight limits will be less than the normal posted weight of the road, and drivers of heavy vehicles should watch for road signs indicating seasonal weight restrictions. Drivers should plan ahead and leave enough time in case a different route needs to be taken to avoid restricted roads.