Chapter 12.60
STREET AND INTERSECTION SIGHT CLEARANCES
Sections:
12.60.020 Obstruction of intersection or shoulder.
12.60.040 Sight distance triangle.
12.60.010 Definitions.
“Intersection” means where two public and/or private streets, roads, alleys, or nonresidential driveways meet or cross.
“Shoulder” means that portion of public or private easement dedicated for a street, road, or alley that is not improved for use of motor vehicles, bicycles, or pedestrians. [Ord. 738B, 2003.]
12.60.020 Obstruction of intersection or shoulder.
The obstruction of a motor vehicle operator’s view on the shoulder or at an intersection shall be prohibited within the sight distance area described in CMC 12.60.040, between a height of three feet and 10 feet above the existing surface of the street. Sight distance areas include the first 20 feet of the shoulder bordering on the improved road and that portion of an intersection that falls into the clear-view triangle as described in this section. A clear-view triangle shall be formed on all intersections by extending two lines of specified length (A) and (B), as designated in CMC 12.60.040, from the center of the intersection along the centerline of both approaches to form the hypotenuse of a triangle. The area within the triangle shall be subject to said restrictions to maintain a clear view on the intersection approaches. [Ord. 738B, 2003.]
12.60.030 Vertical clearance.
Trees or other vegetation projecting over the improved street shall be maintained no lower than 12 feet above the surface of the street. [Ord. 738B, 2003.]
12.60.040 Sight distance triangle.
A. The following charts identify corner intersection sight distances as they relate to speed limits for both stop and yield controlled or uncontrolled intersections.
B. For the purposes of stop controlled intersections, the corner intersection sight distance for the minor street shall be measured from a point on the minor road at least 15 feet from the edge of the major road pavement and measured from a height of eye at three and one-half feet on the minor road to a height of object at four and one-fourth feet on the major road.
|
Sight Distance (Feet) |
|||
|
Operating Speed (MPH) |
Intersection Sight Distance (Stop or Yield Controlled) |
Stopping Sight Distance |
|
|
2 Lanes |
4 + Lanes |
||
|
20 |
210 |
230 |
125 |
|
25 |
255 |
280 |
150 |
|
30 |
310 |
340 |
200 |
|
35 |
355 |
390 |
250 |
|
40 |
410 |
450 |
325 |
|
Operating Speed (MPH) |
Sight Distance (Feet) |
|
|
(A) Major Street |
(B) Minor Street |
|
|
(Uncontrolled) |
||
|
20 |
90 |
90 |
|
25 |
110 |
110 |
|
30 |
130 |
130 |
|
35 |
155 |
155 |
|
40 |
180 |
180 |
[Ord. 738B, 2003.]
12.60.050 Exclusions.
Sight obstructions that may be excluded from these regulations include fences in conformance with this title; utility poles; regulatory signs; trees trimmed from the base to a height of 10 feet above the street; places where the contour of the ground is such that there can be no cross-visibility at the intersection; saplings or plant species of open growth habits and not in the form of a hedge which are so planted and trimmed as to leave at all seasons a clear and unobstructed cross-view; buildings constructed in conformance with the provisions of appropriate zoning regulations; and preexisting buildings. [Ord. 738B, 2003.]
12.60.060 Special cases.
Where unusual conditions preclude the application of the provisions of this chapter in a reasonable manner, the public works director may establish minimum sight distances based on the intent of this chapter. These minimum sight distances may be more restrictive than provided elsewhere in this chapter. [Ord. 738B, 2003.]