Sec. 13-32. - Road and driveway horizontal curves and intersections.

(a)

No road or driveway shall have a horizontal inside radius of curvature of less than fifty feet (50'). An additional surface width of four (4) feet shall be added to curves of fifty (50) through one hundred (100) feet radius; two (2) feet to those from one hundred (100) through two hundred (200) feet. The length of vertical curves in roads, exclusive of gutters, ditches and drainage structures designed to hold or divert water, shall not be less than one hundred feet (100'). If the road or driveway width is less than twenty-four feet (24'), then additional road or driveway widths shall be required as follows:

(1)

Four feet (4') of additional width for curves with a horizontal inside radius of fifty feet (50') to one hundred feet (100') and a central angle greater than forty-five (45) degrees; and

(2)

Two feet (2') of additional width for curves with a horizontal inside radius of one hundred feet (100') to two hundred feet (200') and a central angle greater than forty-five (45) degrees.

The road shall have the full width widening beginning at the point of tangency of the curve requiring the widening to the end point of tangency of that curve or subsequent curves requiring widening (if reverse curves are used). A five-to-one (5:1) taper shall be used to transition from the base width into and out of the widened width.

(b)

Unless otherwise approved by the county fire warden/fire marshal, where a private road, with a throat width equal to or greater than eighteen feet (18') as measured thirty feet (30') from the edge of pavement, intersects a public road, the edge of pavement radius shall begin with a line a minimum of twelve feet (12') from and parallel to the physical centerline of the public road and a minimum radius of twenty-five feet (25') shall be provided from this point to the point of tangency with the edge of pavement of the private road. A taper of not less than ten-to-one (10:1) shall be provided along the public road when the public road is less than twenty-four feet (24') wide.

(c)

Where a private road, with a throat width measuring equal to or greater than twelve feet (12') and less than eighteen feet (18') or a driveway with a throat width equal to or greater than ten feet (10') as measured thirty feet (30') from the edge of pavement, intersects a public or private road, the edge of pavement radius shall begin with a line a minimum of twelve feet (12') from and parallel to the physical centerline of the public or private road and a minimum radius of twenty-five feet (25') shall be provided from this point to the point of tangency with the edge of pavement of the private road or driveway. A taper of not less than ten-to-one (10:1) shall be provided along the public or private road when the public or private road is less than twenty-four feet (24') wide. In lieu of a ten-to-one (10:1) taper connecting private road or driveway to private road only, a radius of forty feet (40') may be used.

(d)

Where a driveway, with a throat width measuring equal to or greater than ten feet (10') and less than eighteen feet (18') as measured thirty feet (30') from the edge of pavement, intersects a private road, the edge of pavement shall be a minimum radius of forty feet (40'). Any driveway with a throat width greater than eighteen feet (18'), as measured thirty feet (30') from the edge of the pavement, that intersects a private road, shall comply with the private road/public road requirements set forth in subsection (b) of this section.

(e)

Road and driveway horizontal curves and intersections may be reduced when proven by scientific method of a recognized vehicle modeling program. The method shall be performed based on the length, width, wheel base and turning radius of a standard Type 1 Fire Apparatus.

(f)

Turnouts shall not be located in a horizontal curve unless additional width is provide. Width shall exceed the minimums set in subsection (a) in addition to the minimum width of the required turnout.

(Ord. No. 6318, § I, 8-11-2020)

State Law reference— California Code of Regulations, Title 14 Natural Resources Code, Division 1.5, Chapter 7, Subchapter 2, Article 1-5, SRA Fire Safe Regulations, 1273.02.