§ 1109.07 STREET GRADES, GRADE CHANGES AND CURVATURE.

   (a)   The grades of streets shall not exceed the percentage shown in Table 1109.02, column 2, except that where unusual or exceptional conditions exist, the City Engineer may modify these regulations. In no event shall the minimum grade of any street or alley be less than .75%.

   (b)   All changes in street grade in excess of 1% shall be connected by vertical curves. Curve length shall be determined using the following formula:

 

K

*

AD

=

L

 

where:

 

K	is the rate of vertical curvature, minimum values of which are shown in Table 1109.02, column 3
AD	is the algebraic difference in grades (%)
L	is the length of the vertical curve, in feet

 

   (c)   The radii of curvature on the center line shall not be less that the radii shown in Table 1109.02, column 4.

 

Table 1109.02 - Street Grade Standards
Type of Street	Maximum Grade	Minimum Rate of Vertical Curve (K)	Minimum Radii of Curvature
Collector streets	7%	50	400 feet
Major arterials	4%	150	400 feet
Minor	10%	20	200 feet
Minor arterials	7%	50	400 feet
Pedestrian ways or crosswalks	12%

 

(Ord. 99-207, passed 1-10-2000)