With the collapse of Soviet Union the traffic loads and available materials significantly changed in Latvia. When joining European Union the situation altered again with new requirements for test methods, road design, and increased traffic flow. Entirely new road construction and pavement design specifications had to be implemented. Largely these were adopted from existing foreign norms albeit in many cases pavements still exhibited premature failure, mostly in form of rutting. To improve the National specifications for asphalt mix design an experimental section consisting of six asphalt concrete and two stone matrix asphalt wearing course sections was paved on Riga bypass in 2001 and monitored until 2012. The experiment was designed to evaluate the use of different mix designs and various types of mineral aggregates, including granite, diabase, and dolomite for the use in high traffic intensity roads. The sections were continuously monitored for bearing capacity, skid resistance, roughness, rutting, and cracking. It was found that the use of dolomite significantly reduces skid resistance, and the use of natural sand increases plastic deformations. Based on these conclusions, changes in the National road specifications were introduced, including flow coefficient test for sand, abrasion and fracture resistance requirements for stone, rutting resistance requirement for mix design and minimum skid resistance requirement for newly constructed pavements.