LAC 70:I.1317. Minimum Design Guidelines for Suburban Arterial Roads and Streets

Item No. | Item | Suburban1 Item No. | Item | SA-1 | SA-2 1 | Design Speed (mph) | 50 | 55 2 | Level of Service | C 3 | Number of Lanes | 2 (min)-4 (typ) 4 | Width of Travel Lanes(ft) | 12 5 | Width of Shoulders (minimum) (ft)2 5 | (a) Inside on multilane facilities | 4 5 | (b) Outside | 8 6 | Shoulder Type | Paved 7 | Parking Lane Width (ft) | N/A 8 | Width of Median on Multilane Facilities (ft) 8 | (a) Depressed | 30–42 | 42 8 | (b) Raised | 30 8 | (c) Two way left turn lane | N/A 9 | Width of Sidewalk (minimum) (where used) (ft)3 9 | (a) When offset from curb | 4 9 | (b) When adjacent to curb | N/A 10 | Fore slope (vertical – horizontal) | 1:4 to 1:6 | 1:6 11 | Back slope (vertical – horizontal) | 1:3 | 1:4 12 | Pavement Cross-slope (%) | 2.5 13 | Minimum Stopping Sight Distance (ft) | 425 | 495 14 | Maximum Superelevation (%) | 4 | 6 15 | Minimum Radius (ft)4, 5 15 | (a) With normal crown (-2.5% cross-slope) | 16,700 | 19,700 15 | (b) With 2.5% superelevation | 3,500 | 5,250 15 | (c) With full superelevation | 1,000 | 1,100 16 | Maximum Grade (%) | 46 | 4 17 | Minimum Vertical Clearance (ft) 7 | 16 18 | Minimum Clear Zone(ft) 18 | (a) From edge of through travel lane | 20 – 288 | 24 18 | (b) Outside from back of curb (when curb is used) | 10 (1:6) 18 (1:4) | 14 18 | (c) Median from back of curb (when curb is used) | 12 | 18 19 | Bridge Design Live Load 9 | AASHTO 20 | Width of Bridges (minimum) (face to face of bridge rail at gutter line) 10 (a) Curbed facilities (without sidewalks) | Roadway width (b) Shoulder facilities | Roadway width 21 | Guardrail Required at Bridge Ends | Yes