The following additional geometric standards and specifications shall apply to all roads covered under this chapter:
A. All roads shall intersect at right angles. Intersection variations shall be as provided in Section 12.04.015.
B. Streets entering upon opposite sides of a given street shall have their centerlines directly opposite each other, or said centerlines shall be offset the following minimum distances:
Arterial road: 300 feet
Collector road: 300 feet
Local road: 150 feet
Cul-de-sac: 150 feet.
Exceptions to this standard may only be considered when traffic impacts are addressed and mitigated to the satisfaction of the planning commission.
C. Drainage improvements shall be designed to carry runoff from a twenty-five-year storm for arterial roads and from a ten-year storm for all other roads.
D. Design flows may be carried in the gutters of urban roads until said flow inundates the closest traffic lane of said road. At that point, the flow shall be delivered downward via drainage inlets to an underground storm drain system where it shall be carried to a natural outlet.
E. Road grades shall be no steeper than twelve percent.
F. Roads shall have a two and one-half percent crown slope.
G. Dead-end roads shall be constructed with turnarounds at the end. The structural section shall be equivalent to the structural section of the adjoining road.
H. Horizontal and vertical alignment shall be consistent with generally accepted engineering practice and take into consideration the topography of the area.
I. Crushed rock for basement material and asphalt concrete, shall be as specified in Section 12.04.015.
J. Minimum curb return radius shall be as follows: Arterial road: 25 feet
Collector road: 25 feet
Local/collector road: 25 feet
Local/local road: 20 feet
Cul-de-sac: 20 feet.
K. For corner lots where curb and gutter is required on one street and not on the other, a full (ninety degree +/-) curb return shall be required.
L. All road structures shall be constructed to carry at least the maximum load and provide the minimum vertical clearance as required by Vehicle Code Sections 35550, 35750, and 35250.
M. All bridges and similar structures shall be founded on permanent foundations, which are capable of withstanding a one-hundred-year flood. The lowest portion of the deck of the bridge shall be elevated a minimum of one foot above the one-hundred-year flood level.
N. Road improvements shall, at a minimum, extend from the nearest county-maintained road, or city street, or state highway, to the furthermost property line of the most remote lot of the development, or to the end of the turnaround area if the road does not go through.
(Ord. 97-17 (part), 1997.)