Idaho Frost Laws, Seasonal Load Weight and Speed Restrictions – 2024

2024 Frost laws for Idaho.

39.03.14 300.SPECIAL PERMIT POLICY DURING SPRING BREAKUP.

Type of Load Restrictions: This rule states the size, weight, or speed limit restrictions the Department may place on the state highway system if the operation of vehicles could cause damage to the road due to climatic or other conditions. Due to conditions, loads will be restricted to one of the following categories in the interests of public safety: (1) Maximum o: legal allowable weight, (2) 16,000 pounds on any axle, (3) 14,000 pounds on any axle, or (4) 12,000 pounds on any axle.

Weight Limits: Normal overweight permit limits will be suspended on all highways in the area when seasonal load and speed restrictions are imposed.

Weight Limits Based on Tire Sizes: In administering load limits based on tire sizes or width, credit for tubed tires will be based on the manufacturer's width marked on the tire. Tubeless tires will be given credit for the width of the conventional tubed tires they replace.

Width Limitation on Two Lane Road: A spring breakup weight restriction to less than legal weight automatically also restricts the width allowed by a special permit to 12 feet 6 inches during the weight restriction period.

Speed Restrictions: Sections of highways posted for maximum loads, trucks, and buses with a gross weight of 10,000 pounds or more will be restricted to a maximum speed of 30 miles per hour. Restricted speed zones will be marked by a red marker that limits speeds to 30 miles per hour and a yellow marker that indicates that the legal speed may be resumed.

Weight Restrictions. Spring breakup weight restrictions limit the weight imposed on the highway by individual axles rather than the total gross weight of vehicles. Therefore, overweight permits may be issued that exceed the  legal allowable total gross load for a vehicle combination subject to these conditions:

a. Minimum tire width is 10 inches or larger.

b. Maximum axle weight on a single axle with two wheels shall not exceed 10,000 pounds.

c. Maximum axle weight on a single axle having four or more tires shall not exceed 14,000 pounds.

d. Permits for nonreducible loads only.

Rules Governing Policy During Spring Breakup Season (39.03.14):

https://adminrules.idaho.gov/rules/2008/39/0314.pdf