La. Admin. Code tit. 70 § I-1317

Current through Register Vol. 50, No. 9, September 20, 2024

Section I-1317 - Minimum Design Guidelines for Suburban Arterial Roads and Streets

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

La. Admin. Code tit. 70, § I-1317

Promulgated by the Department of Transportation and Development, Office of Highways/ Engineering, LR 30:810 (April 2004), repromulgated LR 30:2336 (October 2004), amended LR 35:2845 (December 2009).

AUTHORITY NOTE: Promulgated in accordance with R.S. 48:35(C).