A. Frost-susceptible materials shall be excavated from the entire right-of-way of each street to a minimum depth of two and one-half feet below the proposed finished grade of the roadway area and to a depth of one and one-half feet below the proposed finished grade of the sidewalk area. Greater depths of excavation may be established by the city manager or his duly authorized agent, depending on soil conditions.

B. Classified pit run subgrade gravel of a maximum of three inches in diameter shall be backfilled or laid to within six inches of the proposed final grade of all roadway and sidewalk areas; roadways shall then be surfaced with crushed rock to a depth of four inches, and sidewalks to a depth of two inches.

C. The middle 16 feet of all alleys shall be improved the same as roadways.

D. All improvements shall be made in accordance with the street and sidewalk requirements of the general plan and such specifications as may be established from time to time by the city manager or his duly authorized agent.

E. Culverts, bridges, drainage ditches, and such other improvements shall be contracted for, and installed, in the same manner as street improvements. (Ord. 152 § 1, 1971; 1978 code § 15.106.13)