§ 153.1067 GEOMETRIC DESIGN.

   Interior streets within the subdivision or development parcel shall conform to the standards described in Table 153.1067(A) below.

   (A)   Row (A): Street Classifications.

      (1)   Street types shall be indicated on the preliminary and final subdivision plats.

      (2)   Lane street types are permitted for a TND or transit-oriented development (TOD) if the abutting buildings are provided with:

         (a)   A National Fire Protection Agency (NFPA) 13D fire sprinkler system in the case of single-family dwelling units, single-family attached dwelling units, two-family (duplex) dwelling units and two-family attached dwelling units;

         (b)   An NFPA 13R fire sprinkler system for multi-family buildings; or

         (c)   An NFPA 13 fire sprinkler system for commercial buildings.

   (B)   Row (B): Right-of-Way. Right-of-way width depends on the number of travel lanes and parking lanes provided. The dimensions are in feet and are a minimum width. The right-of-way includes all travel lanes, medians, sidewalks and bike lanes.

   (C)   Row (C): Travel Lanes. Row (C) refers to the number of travel lanes required. Travel lanes shall be a minimum of:

      (1)   Nine feet for lanes and local streets (traditional street design criteria);

      (2)   Ten feet in width for alleys, local roads, and rural streets;

      (3)   Eleven feet in width for avenues, main streets, boulevards, and subcollectors; and

      (4)   Twelve feet for all other streets.

   (D)   Row (D): Parking Lanes. Row (D) refers to the minimum number of parking lanes. If two lanes are required, one parking lane shall be provided on each side of the street. Parking lanes shall be a minimum of eight feet in width. For local streets and subcollectors, excluding rural streets, one parking lane may be included, in which case total required pavement width shall increase by an additional eight feet.

   (E)   Row (E): Pavement Width. Row (E) refers to the minimum width of the traveled way and any parking lanes, in feet, from the back of the curb (BOC) for curbed streets and to the edge of the pavement for all other streets. All streets shall be paved with a hard surface. Gravel or other loose surfacing material is not permitted.

   (F)   Row (F): Corner Radius. Row (F) refers to the minimum radius, in feet, of the curb located at the street intersection of a block corner.

   (G)   Row (G): Centerline Radius. Row (G) refers to the radius, in feet, described by the radius of the circle formed by a curve that is tangent to the centerline of the road.

   (H)   Row (H): Drainage. In Row (H), “CG” means curb and gutter; “A” means any combination of curb and gutter, swales, and shoulders; “SW” means swales; and “SH” means shoulders. All curbed streets shall be built in accordance with the IDOT Specifications for vertical curb and gutter construction. Gutters shall be at least two feet in width, while gutters for lanes and street medians shall be at least one foot. For rural streets, the City Manager may waive the requirement for curb and gutter where buildings or structures are located on only one side of the street, and the lots or parcels abutting the opposite side of the street are reserved for parks or open space. For a promenade, the curb and gutter may be installed on one or both sides of the facility.

   (I)   Row (I): Grade. Row (I) refers to the maximum slope of a street, in percent. Street and alley grades shall conform to the terrain. No street or alley grade shall be less than 0.5% if curb and gutter are provided. The minimum cross-slope of a road shall be 2% and the maximum shall be 4%.

 

Table 153.1067(A): Functional Street Classification System
Classification	Definition	Average Daily Traffic Range	Subclassifications
Arterial	A high-volume street connects communities and activity centers, and connects communities to major state and interstate highways	Over 3,000	Parkway Freeway Expressway
Collector	As the principal traffic artery within residential or commercial areas, the collector carries relatively high traffic volumes and conveys traffic from arterial streets to lower-order streets. Its function is to promote the free flow of traffic	1,000 - 3,000	Boulevard Main street
Local street	As the lowest-order street, the access street usually carries no through traffic. With properly designed access streets without through traffic, travel distances from residences to collector streets are short, traffic speeds are low, lane capacity and design speed are not controlling design factors, and minor delays are inconsequential considerations. Drivers and residents expect and accept both brief delays and the need to decrease speed	0 - 250	Local streets Rural streets Cul-de-sacs Alleys
Subcollector	The subcollector provides passage to access streets and conveys traffic to collectors. Like access streets, the subcollector provides frontage and access to residential lots but also carries some through traffic to lower-order (access) streets. The subcollector is a relatively low-volume street	250 - 1,000	Avenue Main street
NOTES TO TABLE: Source: United States Department of Housing and Urban Development, Proposed Model Land Development Standards and Accompanying State Enabling Legislation (Upper Marlboro, MD: National Association of Home Builders Research Center, June 1993), at 11; see also Institute of Transportation Engineers, “Guidelines for Residential Subdivision Street Design”, ITE Publication No. RP-011C (Washington, DC: ITE, 1993), at 1; see also John D. Edwards, ed., Transportation Planning Handbook (Washington, DC: Institute of Transportation Engineers, 1999).

 

Table 153.1067(B): Street Geometric Design
Conventional Design Streets
A	Local road
B	Right-of-way	42 - 50 feet
C	Travel lanes	2
D	Parking lanes	0
E	Pavement width	20 - 28 feet
F	Corner radius	15 feet
G	Centerline radius	90 feet
H	Drainage	CG
I	Grade	15%
J	Median	0
K	Block length	700 feet
L	Sidewalks	5 feet
M	Planting strip	6 feet
N	Bike lanes	NA
O	Trees	Yes
A	Subcollector
B	Right-of-way	66 feet
C	Travel lanes	2
D	Parking lanes	1
E	Pavement width	36 feet
F	Corner radius	15 feet
G	Centerline radius	90 feet
H	Drainage	CG
I	Grade	8%
J	Median	0
K	Block length	NA
L	Sidewalks	5 feet
M	Planting strip	10 feet
N	Bike lanes	Yes
O	Trees	Yes
A	Collector
B	Right-of-way	80 feet
C	Travel lanes	2
D	Parking lanes	1
E	Pavement width	38 feet
F	Corner radius	25 feet
G	Centerline radius	250 feet
H	Drainage	A
I	Grade	8%
J	Median	0
K	Block length	NA
L	Sidewalks	5 feet
M	Planting strip	10 feet
N	Bike lanes	Yes
O	Trees	Yes
A	Arterial
CONVENTIONAL DESIGN STREETS
B	Right-of-way	70 - 118 feet
C	Travel lanes	2
D	Parking lanes	0
E	Pavement width	24 - 72 feet
F	Corner radius	25 feet
G	Centerline radius	250 feet
H	Drainage	SH
I	Grade	8%
J	Median	0
K	Block length	NA
L	Sidewalks	NA
M	Planting strip	10 feet
N	Bike lanes	Yes
O	Trees	Yes
COMMUNITY DESIGN STREETS
A	Alley
B	Right-of-way	20 feet
C	Travel lanes	1
D	Parking lanes	0
E	Pavement width	10 feet
F	Corner radius	10 feet
G	Centerline radius	50 feet
H	Drainage	NA
I	Grade	10%
J	Median	0
K	Block length	400 feet
L	Sidewalks	NA
M	Planting strip	NA
N	Bike lanes	NA
O	Trees	NA
A	Lane
B	Right-of-way	38 feet
C	Travel lanes	2
D	Parking lanes	0
E	Pavement width	18 feet
F	Corner radius	10 feet
G	Centerline radius	90 feet
H	Drainage	CG
I	Grade	10%
J	Median	0
K	Block length	150 feet
L	Sidewalks	5 feet
M	Planting strip	5 feet
N	Bike lanes	NA
O	Trees	NA
A	Local street
B	Right-of-way	48 - 56 feet
C	Travel lanes	2
D	Parking lanes	1
COMMUNITY DESIGN STREETS
E	Pavement width	26 - 34 feet
F	Corner radius	10 feet
G	Centerline radius	90 feet
H	Drainage	CG
I	Grade	12%
J	Median	0
K	Block length	300 feet
L	Sidewalks	5 feet
M	Planting strip	6 feet
N	Bike lanes	NA
O	Trees	Yes
A	Rural street
B	Right-of-way	38 feet
C	Travel lanes	2
D	Parking lanes	0
E	Pavement width	20 feet
F	Corner radius	15 feet
G	Centerline radius	90 feet
H	Drainage	SW
I	Grade	15%
J	Median	0
K	Block length	NA
L	Sidewalks	NA
M	Planting strip	NA
N	Bike lanes	NA
O	Trees	Yes
A	Avenue
B	Right-of-way	59 - 118 feet
C	Travel lanes	2
D	Parking lanes	0-2
E	Pavement width	22 - 50 feet
F	Corner radius	15 feet
G	Centerline radius	250 feet
H	Drainage	CG
I	Grade	8%
J	Median	0
K	Block length	NA
L	Sidewalks	6 - 20 feet
M	Planting strip	10 feet
N	Bike lanes	Yes
O	Trees	Yes
A	Main street
B	Right-of-way	68 - 130 feet
C	Travel lanes	2 - 4
D	Parking lanes	2
E	Pavement width	48 - 70 feet
F	Corner radius	15 feet
G	Centerline radius	600 feet
H	Drainage	CG
COMMUNITY DESIGN STREETS
I	Grade	8%
J	Median	0
K	Block length	300 feet
L	Sidewalks	10 feet
M	Planting strip	NA
N	Bike lanes	Yes
O	Trees	Yes
A	Boulevard
B	Right-of-way	90 - 168 feet
C	Travel lanes	4 - 6
D	Parking lanes	0 - 2
E	Pavement width	44 - 94 feet
F	Corner radius	25 feet
G	Centerline radius	500 feet
H	Drainage	A
I	Grade	8%
J	Median	14
K	Block length	1,000 feet
L	Sidewalks	6 - 20 feet
M	Planting strip	10 feet
N	Bike lanes	Yes
O	Trees	Yes
NOTES TO TABLE: NA = the standard does not apply. For rules of interpretation, see subsections “Row (A): Street Classifications” through “Row (O): Trees” of this chapter. Where a number is stated as a range, the street may include any dimension or number within the range at the discretion of the applicant. The methodology for calculating the geometric design factors shall conform to the engineering specifications and AASHTO Green Book: A Policy on Geometric Design of Highways and Streets, 5th ed. (Washington, DC: American Association of State and Highway Transportation Officials, 2004), unless a different standard is prescribed in this section.

 

   (J)   Row (J): Median.

      (1)   Width. Where median widths are specified in Row (J), a median of at least the designated width shall be provided.

      (2)   Entrance roads. Entrance roads shall include a median that complies with these requirements. Islands and medians shall be a minimum of 75 square feet in size.

      (3)   Visibility. Structures, permanent materials or plantings within the island shall not obscure the visibility of cars entering a cross street for a distance of 20 feet back from the curb face of the cross street, unless a larger setback is needed due to inadequate sight distance created by horizontal or vertical curve alignment.

      (4)   Planting materials. Large to medium trees shall be planted within the median. The minimum median width for tree planting is 18 feet. Where left turn lanes are provided, the minimum width is eight feet.

      (5)   Spacing. One medium tree shall be planted every 50 feet and shall be a minimum of six feet from the BOC. Where left turn lanes and/or crossovers are provided, the planting shall begin 15 feet from the nose of the turning island. Preservation of existing trees and understory vegetation may be used to meet this requirement.

   (K)   Row (K): Block Length. Row (K) is the maximum block length, in feet.

   (L)   Row (L): Sidewalks. Row (L) refers to the minimum and maximum width, in feet, of sidewalks. For parkways, the sidewalks shall take the form of multi-use greenways, which may meander at a distance of between six to 15 feet from the paved section of the roadway. (See § 153.1074 of this chapter for sidewalk design requirements). Sidewalks shall be provided on both sides of the pavement section for all streets.

   (M)   Row (M): Planting Strip. Row (M) refers to the minimum width, in feet, of the planting strip, located between the curb and sidewalk parallel with the street. For main streets, grated tree wells shall be used in lieu of planting strips.

   (N)   Row (N): Bike Lanes.

      (1)   Row (N) indicates whether bike lanes are required. Bike lanes may be included as individual bike lanes reserved for bicyclists, combined with trails, or striped as part of the street system. Bike lanes shall conform to the geometric design criteria as shown in Table 153.1068(A) of this chapter.

      (2)   Bike lanes shall connect to and align with the city’s bike lane plan and bike lanes on abutting property. Dimensional standards for bike route signage shall comply with the Manual on Uniform Traffic Control Devices (MUTCD). Bike paths shall be paved with a minimum 2-inch thick asphaltic concrete top course placed on a six-inch thick select granular subbase. The right-of-way outside of the paved lane shall be graded to provide clearance from trees, poles, walls, fences, guardrails or other lateral obstructions.

   (O)   Row (O): Trees. Column (O) indicates whether street trees are required. Street tree planting areas shall be a minimum of four feet. Street trees shall be located within the right-of-way on both sides of and parallel to the street. If sidewalks are used, street trees shall be located between the sidewalk and curb.

(Ord. 3020, passed 9-10-2013, § 5.23.3)