Driveway ramps for parking structures shall conform to the standards prescribed in this division.
(Ordinance 1929 adopted 9/23/13)
For the purpose of construing and enforcing this division, certain abbreviations, words, terms, phrases and their derivatives shall have the same meaning and/or be consistent with their use and meaning in division 2 of this article. All other words shall have their usual meaning.
(Ordinance 1929 adopted 9/23/13)
(a) 
The width of the ramp, radii for all curves, length of the landing area and the percent of slope, the length of the ramp at the specified slope, and design elevations on both sides of the ramp at all break points (plus along the center of travel lanes in curves) must be shown on the plan and profile presented to the building inspection department with an application for a building permit for a parking structure, either above-ground or underground, that requires a ramp up or down from the grade of the base of the structure.
(b) 
All horizontal and vertical curves for ramps shall have adequate sight stopping distance and entrance and exit points to ensure public safety.
(c) 
Horizontal alignment that approximates the geometric requirements of circular curves and tangents shall be used. All vertical curves shall be parabolic, have equal tangents, and a change in curvature that is constant.
(d) 
The principal control in the design of crest vertical curves is to ensure that stopping sight distance (SSD) is available throughout the vertical curve.
(e) 
The principal control in the design of sag vertical curves is to ensure that stopping sight distance (SSD) is available for headlight illumination throughout the sag vertical curve.
(Ordinance 1929 adopted 9/23/13)
(a) 
Design speed (DS): 5 mph.
(b) 
Design vehicle (high-profile vehicle): 80.0 inches.
(c) 
Design vehicle (minimal under-body clearance): 5.6 inches.
(d) 
Stopping sight distance (SSD) object height: 2.0 feet.
(Ordinance 1929 adopted 9/23/13)
The driveway within the right-of-way shall have a minimum elevation change of +0.5 feet. Sidewalks shall meet slope criteria of the Americans with Disabilities Act (ADA).
(Ordinance 1929 adopted 9/23/13)
All ramps shall have a landing area with a maximum slope of one (1) vertical unit in twelve and one-half (12.5) horizontal units, or eight percent (8%). The landing area shall have a minimum length of fifteen feet (15') measured from the intersection of the ramp and the property side of the sidewalk of the site. No vertical curve shall be allowed within the landing.
(Ordinance 1929 adopted 9/23/13)
(a) 
Parking garages on commercial properties that provide twenty-five (25) or fewer parking spaces shall have, at a minimum, one (1) access ramp to facilitate two-way traffic.
(b) 
Parking garages that provide twenty-six (26) or more parking spaces shall have, at a minimum, one (1) access ramp to facilitate two-way traffic. Sites with parking structures that provide twenty-six (26) or more parking spaces may have two (2) or more one-way access ramps in lieu of one (1) two-way access ramp.
(Ordinance 1929 adopted 9/23/13)
(a) 
The maximum slope for the ramp, other than the landing area, shall be one (1) vertical unit in eight (8) horizontal units, or twelve and one-half percent (12.5%).
(b) 
At the top and bottom of the ramps, vertical curves shall be used to provide smooth transitions at all changes in slope.
(c) 
The driveway surface entering into a subterranean parking structure shall not be more than thirty (30) inches below the natural front yard grade when the driveway is located between the front property line and the front building line.
(Ordinance 1929 adopted 9/23/13)
(a) 
The minimum width for a one-way ramp is twelve feet (12'), with an additional one foot (1') on each side for clearance to the structure and/or retaining wall, or a total minimum width of fourteen feet (14').
(b) 
Ramp widths shall be measured from face to face of any side curbs, walls or structures, and shall be the width of the actual driving surface. On sites providing twenty-six or more parking spaces, ramps less than twenty feet (20') in width shall be posted for one-way traffic. On sites where a single ramp less than twenty feet (20') wide is allowed, signage shall be posted warning drives of potential oncoming ramp traffic.
(c) 
Convex mirrors, placed on private property, are required where opposing motorists cannot readily view each other and/or where ramps are too narrow to permit vehicles to bypass each other.
(Ordinance 1929 adopted 9/23/13)
All ramps shall have at least ten feet (10') sight triangles through which drivers can see pedestrians in the right-of-way. The ten feet (10') sight triangles shall be measured from the intersection of the ramp and the property side of the sidewalk of the site.
(Ordinance 1929 adopted 9/23/13)