Section 39.03.47.100 - DETERMINATION OF AN IMPROVED ROAD01.Status of Improvement. Highways laid out and marked to include four (4) or more travel lanes shall be considered as two (2) roadways and mileage for each roadway will be eligible for inclusion in the inventory dependent on Status of Improvement as provided below.02.Road Inventory Determination of an Improved Road. The "Road Inventory Determination of an Improved Road" sets forth standards for an improved road.Idaho Admin. Code r. 39.03.47.100