Design Speed
(miles per hour)
|
Minimum Radius of Horizontal Curves
(feet)
|
Maximum Percent of Grade
(feet)
|
Minimum Forward Sight Distance
(feet)
|
Minimum Length of Vertical Curve for each
1% Change in Grade
(feet)
|
---|---|---|---|---|
20
|
100
|
10
|
150
|
10
|
25
|
200
|
10
|
175
|
15
|
30
|
250
|
10
|
200
|
20
|
35
|
350
|
10
|
250
|
30
|
40
|
450
|
8
|
275
|
35
|
45
|
600
|
8
|
325
|
55
|
50
|
750
|
8
|
350
|
70
|
Through
|
Commercial
|
Local
| |
---|---|---|---|
Minimum right-of-way (feet)
|
60
|
60
|
50
|
Grading width (feet)
|
60
|
60
|
50
|
Pavement width (feet)
|
34
|
40
|
24
|
Maximum grade
|
8%
|
8%
|
10%
|
Minimum grade
|
1%
|
1%
|
1%**
|
Minimum curb radii (feet)
|
30
|
30
|
20
|
Minimum tangent length between reverse curves
(feet)
|
200
|
200
|
*
|
Maximum grades within 150 feet of center line
intersections
|
1.5%
|
1.5%
|
1.5%
|
Minimum distance between center line offsets
at street jogs (feet)
|
150
|
150
|
150
|
Maximum length of cul-de-sac (feet)***
|
---
|
---
|
800
|
Minimum outside radius of cul-de-sac pavements
(feet)
|
---
|
---
|
45
|
Angle at intersections of street center lines
|
90°
|
90°
|
90°
|
NOTES:
|
*One hundred feet, except where excessive grades
may be reduced to reasonable grades by shortening tangent.
|
**Grades under 1.0% acceptable when approved
stormwater drainage facilities are provided.
|
***Except where, in the judgment of the Planning
Board, the cul-de-sac does not impose any problem and constitutes
a positive design feature.
|
[NOTE: Standards are not shown for arterial
streets, as they would in all probability be built by the state or
county.]
|