Jan 6, 2017 · All alley pavements are to be nstructed over properly stabilized and mpacted subgrade. Pavement Design: Alley Pavement Depth. Land Use Zone. Pavement Type and Depth. 1 or 2 new dwelling units. 6″ Roadway Cement ncrete. or. 3″ Asphalt (HMA Cl 1/2″) over 6″ Crushed Rock (Type 2 Mineral Aggregate) SF, LR1, LR2, LR3, MR, HR.