Section II. Streets

A.    GENERAL CONDITIONS

All streets shall be designed and constructed in accordance with the design criteria for the various classes as established in the “Bureau of Local Roads and Streets (BLRS) Manual” and “Highway Standards” of the State of Illinois Department of Transportation (IDOT), latest edition.  When certain design criteria in the BLRS Manual reference the IDOT “Bureau of Design and Environment (BDE) Manual”, the BDE Manual shall be considered design criteria.  Construction materials and methods shall meet the requirements of the “Standard Specifications for Road and Bridge Construction” and the “Supplemental Specifications and Recurring Special Provisions”, latest edition.  Construction shall also meet the requirements of the current applicable IDOT BDE Special Provisions that are issued four times per year, and current District 1 Special Provisions.  

All Streets shall also be designed and constructed to comply with the City’s adopted Complete Streets Policy to provide a safe and convenient travel experience for users of all ages and abilities that accommodates pedestrians, bicyclists, motorists, individuals with disabilities and public transportation users.

All roadways shall have concrete curb and gutter Type B-6.12 modified as detailed in Exhibit II-C-4 and II-C-5 of the Appendix herein.

B.    STREET DESIGN

1.    Geometric Considerations

All proposed roadway classifications shall be consistent with the City of Aurora Comprehensive Plan.

All intersections with Major Collector or Arterial streets shall provide a 25 foot minimum right-of-way triangle. If deemed necessary by the City Engineer, a larger right-of-way triangle may be required.

Vertical curves are required on Local Residential and Minor Collector streets when the algebraic difference between successive longitudinal profiles is greater than one and one half percent (1.5%).  For all other street classifications, vertical curves shall be designed in accordance with the current edition of the IDOT BLRS Manual.  The minimum length of vertical curve in Table 1 may be modified if needed to meet the maximum K value requirements of the BLRS Manual.

Street jogs with centerline offsets shall be avoided if the centerline offset is less than one hundred twenty-five feet (125’) for Local streets at Local streets, or two hundred feet (200’) for Local streets at Minor Collector streets.

Streets shall be laid out so as to intersect as nearly as possible at right angles and, where practical, no street shall intersect any other street at less than eighty (80) degrees.

Dead-end streets (cul-de-sac) designed to be permanent shall be provided at the closed end with a paved turnaround having dimensions as indicated on Exhibits II-B-6 and II-B-7 and shall not be longer than five hundred feet (500’) from the centerline of the intersecting street to the radius point.


Table 1: Streets shall conform to the following table of minimum standards: 

Street

Right-of-Way Width (feet)

Roadway Width from Back-of-Curb to Back-of-Curb (feet)

Radius of Horizontal Curves (feet)

Length of Vertical Curves (feet)

Tangent Between Reverse Curves (feet)

Distance Between

 Drive Openings and Intersecting Curves 

(feet)

LOCAL

Residential

66

31

200

100

100

NA/125

Cul-de-sac

66

31

200

100

100

NA/125

Industrial and Commercial

66

39

500

200

200

NA/125

COLLECTOR

Minor

80

39

400

150

150

200

Major

Variable; 80 min.

Variable;

 41 min.

475

175

175

NA/400

ARTERIAL

 

Variable; 100 min.

49 min.

500

200

200

1200

Street

Maximum Gradient (Percent)

Minimum Gradient (Percent)

Posted Speed Limit

Minimum Clear Sight Distance (feet)

Intersection Curb Radii (Feet)

LOCAL

Residential

6

0.40

--

*

30

Cul-de-sac

6

0.40

--

*

30

Industrial and Commercial

2

0.40

--

*

35

COLLECTOR

Minor

6

0.40

--

*

35

Major

4

0.40

--

*

40

ARTERIAL

 

--

0.40

30

*

50

 

 

 

35

*

 

 

 

 

40

*

 

 

 

 

45

*

 

 

 

 

50

*

 

 

 

 

55

*

 

*The minimum clear sight distance shall be determined using the procedures described in Chapter 28 of the BLRS Manual.

Where existing streets are being widened for required improvements along the frontage of a development, grades shall be provided along the existing edge of pavement, along the existing centerline, and along the proposed curb and gutter at intervals of twenty five feet (25’).

On all streets where new pavements meet existing pavements, transitional pavements shall be provided in accordance with the latest version of IDOT District 1 Detail BD-32, Butt Joint and HMA Taper details.

2.    Pavement Section

The City will require a pavement design for Industrial and Commercial roadways, Minor Collectors, Major Collectors, and Arterials that shall be determined in accordance with the current edition of the IDOT BLRS Manual, or as otherwise required by the jurisdictional authority.  Design Standards shall not be less than for Class III roads and based on a twenty (20) year pavement design.  Typical pavement thicknesses for various road classifications are listed in Table 2 of this Section.  Asphalt mixes and minimum thicknesses of each mix shall be according to the current IDOT District 1 “Hot Mix Asphalt – Mix Selection” table for the projected traffic.  The pavement design shall be a Full-Depth Hot Mix Asphalt (HMA) pavement per IDOT BLRS Manual Chapter 44-4 and submitted to the City Engineer for approval.

The HMA mixtures shall be designed, produced, and constructed in accordance with the most current IDOT specifications, policies, and procedures.  This includes current District 1 Special Provisions that from time-to-time are amended, deleted from and added to, including “Friction Aggregate”, “Ground Tire Rubber (GTR) Modified Asphalt Binder”, “Reclaimed Asphalt Pavement (RAP) and Reclaimed Asphalt Shingles (RAS)”, and “HMA Binder and Surface Course”.  All HMA shall be an IDOT approved mix and submitted to the City Engineer for approval. 

Table 2 below indicates typical design pavement thicknesses for each roadway material for various road classifications.  In addition, the CA-6 base course shall be compacted to a minimum ninety-five percent (95%) modified laboratory density in accordance with AASHTO T99 method A or C.

Table 2: Typical Cross Sections for Various Road Classifications

 

Minimum Aggregate

Average Daily Traffic

Multiple Unit

Single Unit

Traffic Factor

Total Pavement Thickness

Local Residential

12" Aggregate Base Course, Type B (CA-6)

N/A

N/A

N/A

N/A

4"

Industrial and Commercial

12" Aggregate Subgrade Improvement or Modified Soil Layer

N/A

N/A

N/A

N/A

6"-12.5"

Minor Collector

12" Aggregate Subgrade Improvement or Modified Soil Layer

1,300-9,900

2%

1%-6%

0.08-2.52

6"-10.75"

Major Collector

12" Aggregate Subgrade Improvement or Modified Soil Layer

2,100-22,900

2%

1%-6%

0.13-5.84

6"-12.5"

Arterial Street

12" Aggregate Subgrade Improvement or Modified Soil Layer

15,100-47,000

1%-5%

2%-5%

1.51-13.05

10"-14.25"

A Soils Report shall be prepared for all proposed roadways.  Streets shall not be constructed on a subgrade having an Illinois Bearing Ratio (I.B.R.) of less than 3.0.  The soil support I.B.R. value selected for use by the designer shall represent a minimum value for the soil to be used.  An adequate number of soil borings shall be obtained to determine the soil characteristics for street and utility construction purposes.  A copy of the Soils Report shall be provided to the City Engineer.   A non-woven drainage fabric (Propex GEOTEX 601, or approved equal) shall be used in conjunction with an open-graded granular base course and under-drain system connected to a storm sewer as approved by the City Engineer.  The subgrade shall be compacted and graded parallel to the finished pavement surface.

When the Soils Report indicates a subbase area below the water table or having poor drainage characteristics, the pavement design must provide additional subbase drainage which will allow the new subgrade to be drained into a storm sewer or roadside ditch system.


C.    STREET CONSTRUCTION

1.  General Considerations

During construction, in no case shall the subbase material be placed on a wet subgrade.  All removal of unsuitable material in the subgrade shall be replaced with compacted clay of proper moisture content to a minimum ninety-five percent (95%) modified laboratory density in accordance with AASHTO T99 (Method A or C).  

The City Engineer may approve lime stabilization when soils are compatible as determined by a geotechnical engineer.  The lime shall be mixed to a minimum depth of sixteen inches (16”) to meet the Illinois Department of Transportation’s guidelines for “Lime Stabilized Soil Mixture” as outlined in the “Standard Specifications for Road and Bridge Construction,” latest edition.  

The subgrade shall drain to the curb line and to the inlets and catch basins.  Water will not be allowed to pocket on the subgrade.  Positive drainage must be accomplished on the compacted subgrade or the placement of base material will not be allowed. Verification by the City Engineer of the proper subgrade drainage will be required prior to any additional roadwork.  

2.  Proof-Rolling

Base material shall not be placed prior to approval of the subgrade by the City Engineer.  The subgrade and base course shall be proof-rolled by the Contractor as described below.  The Contractor shall contact the City Engineer a minimum of forty-eight (48) hours prior to the proof-roll.  The proof-roll shall be performed by the Contractor and witnessed by the City Engineer.  The proof-roll will be conducted as follows.

  1. A loaded truck shall be driven over the area to be tested at a speed, pattern, and number of cycles to be determined by the City Engineer.  The test truck shall be the common tractor-trailer type with no more than five (5) axles with a total of eighteen (18) wheels loaded to a net weight of no less than twenty-two (22) tons.
  2. Any unstable or damaged subbase, base course, or binder course shall be removed and replaced to the satisfaction of the City Engineer at no cost to the City.
  3. The City Engineer is responsible for determining whether the proof-roll passes or fails.   The Contractor is responsible for determining how to fix any unsatisfactory areas.

The City Engineer will not witness proof-rolling of privately-owned paved areas.

3.  Asphalt Paving

All paving shall be done with a tracked paving machine utilizing electronic grade control of a minimum length of fifteen feet (15’), but the length of the machine shall be suitable for the width of the road and be verified as acceptable to the City Engineer.  The asphalt laying pattern must be approved by the City Engineer in order to minimize longitudinal joints.  A certified nuclear density technician must be on site to set the asphalt rolling pattern and confirm compaction densities.  The technician shall revise the rolling pattern as deemed necessary.  The technician shall stop the paving operation if the required densities are not being met.  Density testing results shall be submitted to the City Engineer within one week of completion of the paving operation.

All asphalt mixtures shall be delivered and handled so that the asphalt mixture immediately behind the paver screed is at or above two hundred seventy (270) degrees Fahrenheit.  All asphalt delivered to the project shall be covered when the air temperature is at or below seventy (70) degrees Fahrenheit.

The asphalt base course, leveling binder, binder course, and surface course mixtures shall be laid on a surface that is dry and only when weather conditions are suitable. The surface course for Major Collectors and Arterials shall be tested for smoothness with a sixteen foot (16’) straightedge according to Article 406.11 of the IDOT Standard Specifications.  Any surface variations which warrant penalties per Article 406.11 will be paid to the City of Aurora assuming a unit price of $100 per ton of asphalt.  When the variation exceeds ¾ inch, requiring removal and replacement at the entire expense of the Contractor, the City Engineer shall mark the limits of the removal.

The asphalt base course, leveling binder, and binder courses shall be placed only when the temperature in the shade is at least forty five degrees Fahrenheit (45° F), when the temperature in the shade for the previous twenty-four (24) hours is at least thirty two degrees Fahrenheit (32° F) and when rising temperatures are forecasted.

After any binder course deficiencies have been corrected to the satisfaction of the City Engineer and immediately prior to placing the asphalt surface course, the pavement shall be thoroughly cleaned and primed with bituminous materials (tack coat) at a residual asphalt rate of 0.05 pounds per square foot.  The pavement shall be primed a minimum of twelve (12) hours prior to placing the asphalt surface course, unless otherwise approved by the City Engineer.  When bituminous materials are applied under traffic conditions, sanding at the approximate rate of two (2) pounds to four (4) pounds per square yard will be required.  All affected residents and businesses shall be notified a minimum of twenty-four (24) hours prior to placement of bituminous materials.

The surface course shall be placed only when the temperature in the shade is at least  forty five degrees Fahrenheit (45° F), when the temperature in the shade for the previous twenty-four (24) hours is at least forty degrees Fahrenheit (40o F), and when rising temperatures are forecasted

Any pavement activity should be stopped in the event of rain, regardless of temperature.  In the event of a sudden rain, the loading of trucks at the asphalt plant or from storage bins shall be ceased immediately.  Material in transit may be laid at the Contractor’s risk, provided the pavement is free of standing water and the proper asphalt temperature is maintained.

Final placement of asphalt surface course shall be delayed for a minimum of one full winter and no longer than three (3) years from the installation of the binder.  Before the placement of the surface course, all underground utility punch list items for final inspection shall be completed and approved.  Also, the binder course patches must be completed and the curb and gutter repaired as required by the City Engineer.

Where the road is being widened to install a left turn lane, surface shall be installed for the entire width along said improvements.

4.  Cold Weather Paving Requirements

The cutoff date for asphalt paving is November 1.   No exceptions will be made for placement of surface course on public roads; however, the City Engineer may approve a written request to allow other asphalt paving after the cutoff date, provided the following requirements are met.

  1. Submit a one (1) day forecast, showing a daytime temperature of forty five (45) degrees Fahrenheit, and rising, from the time of asphalt placement.
  2. Provide the Contractor’s name, Contractor’s phone number, Customer’s name, Customer’s address and Customer’s phone number.
  3. Requests that are approved will require a pre-placement inspection by the City, which must be scheduled a minimum of twenty four (24) hours in advance.
  4. Requests that are approved will also require independent certification of the density by a testing firm, if the temperature drops below forty five (45) degrees Fahrenheit between the time of placement and final compaction.
  5. These additional measures are the responsibility of the individual requesting the variance.  Density testing reports shall be submitted to the City under cover letter indicating the address and date of the asphalt placement.

The cutoff date for concrete paving is October 25; however, the City Engineer may approve a written request to allow concrete paving after the cutoff date, provided the following requirements are met.

  1. Submit a seven (7) day forecast, showing both daytime highs and nighttime lows from the date of concrete placement.
  2. Provide the Contractor’s name, Contractor’s phone number, Customer’s name, Customer’s address and Customer’s phone number.
  3. Requests that are approved will require a pre-placement inspection by the City, which must be scheduled a minimum of twenty four (24) hours in advance.
  4. Requests that are approved may also require:

    1. The placement of two (2) layers of polyethylene sheeting, twenty four (24) hours in advance of low temperatures, when projected temperatures in the seven (7) day curing window are forecast to be thirty two (32) degrees Fahrenheit or lower;
    2. Independent certification that the thermal protection was deployed and maintained when temperatures in the seven (7) day curing window were thirty two (32) degrees Fahrenheit or lower; and
    3. Verification of the concrete strength through destructive testing of concrete cylinders, as required by the City Engineer.
    4. These additional measures are the responsibility of the individual requesting the variance.  Any reports resulting from these measures shall be submitted to the City under cover letter indicating the address and date of the concrete placement.

5.  Pavement Patching

Open-cutting of City streets is to be avoided at all times.   However, if work necessitates the excavation of street pavement, proper permit and contractor licensing is required.   Pavement patching shall meet the construction requirements as detailed in Exhibits II-C-1, II-C-2 and II-C-3 located in Appendix A.

All work done after the paving cutoff date shall be considered temporary and shall be maintained throughout the winter by the Contractor until a permanent patch is made.

6.  Curb and Gutter

All roadways shall have concrete curb and gutter Type B-6.12 modified as detailed in Exhibit II-C-4 and II-C-5 of the Appendix herein.  All concrete curb and gutter shall be continually reinforced with two (2) No. 4 deformed reinforcing bars between expansion joints.  Expansion joints shall be constructed at intervals of one hundred feet (100’), all points of curvature, five feet (5’) from each side of drainage structures, and between separate pours.  Contraction joints shall be constructed at intervals of ten feet (10’), as indicated in Exhibit II-C-5 of the Appendix herein.  The curb shall be installed on a minimum of four inches (4”) of open graded granular material (crushed stone, gradation CA-7).  The compacted curb subgrade shall be shaped parallel to the curb flow line and positively drained to the inlets and catch basins so that any water, if applied, would not pocket in this subgrade.

7.  Sidewalks

All public sidewalks shall be constructed of concrete with the following specifications.

  1. The concrete used shall be Class “SI” concrete. Membrane curing shall be applied as specified in Section 1020.13(a) (4) of the State of Illinois “Standard Specifications for Road and Bridge Construction”, latest edition.  W. R. Meadows CS-309 Cure & Seal, or approved equal such as Okon S-20, shall be used per manufacturer’s specifications.
  2. The base shall be four inches (4”) of compacted crushed stone base on a dry natural or compacted subgrade.  In no case shall the base be placed on a subgrade of topsoil or other unsuitable material.
  3. The sidewalk shall be five feet (5’) wide and shall be placed within the right-of-way, one foot from the property line. The sidewalk shall be placed a minimum of five inches (5”) thick.  At all residential drive locations and at all sidewalk curb ramp locations, this minimum thickness shall be six inches (6”).  At all commercial drive locations this minimum thickness shall be eight inches (8”).
  4. The surface finish shall be a light broom finish.
  5. Sidewalk curb ramps with a detectable warning surface shall be constructed at all crosswalks according to the applicable IDOT Standard, latest revision, BDE Manual and the Exhibit II-C-6.   Detectable warning tiles shall be a red IDOT approved product with a five (5) year warranty manufactured by ADA Solutions, Inc. or approved equal.
  6. The sidewalk shall be constructed with contraction joints at five foot (5’) intervals and shall be saw cut to a minimum depth of one inch (1”) full width within twenty-four (24) hours of concrete placement, or tooled at the time of placement to the same depth.
  7. Expansion joints of three-fourths inches (3/4”) full depth bituminous fiber material are required where the new sidewalk abuts all curb, buildings, poles, other structures, through all drives on each side, and at regular intervals of one hundred feet (100’).
  8. Class SI concrete, as specified in the IDOT “Standard Specification for Road and Bridge Construction”, shall be used on all sidewalks.  A receipt from the concrete supplier with this information and the location and date of the pour shall be submitted to the City prior to any City approvals of said work.
  9. The Contractor shall notify the City Engineer forty-eight (48) hours prior to placing the concrete for an inspection of the base and formwork.
  10. Where carriage walks are approved by the City Engineer, the carriage walk shall be a minimum of seven (7) feet wide.  The joint between the back-of-curb and sidewalk shall meet the Expansion Joint Detail II-C-12 and dowels shall be placed every three feet (3’) on center and the concrete shall be a minimum of six inches (6”) thick.
  11. Sidewalk shall be designed at a one and one half percent (1.5%) cross slope.
  12. Sidewalk located in the right-of-way shall be designed and constructed according to Public Right-of-Way Accessibility Guidelines (PROWAG), or the current ADA guidance for facilities in the right-of-way.

8.  Shared-Use Paths

Shared-Use Paths shall be ten feet (10’) in width.   A width of eight feet (8’) is acceptable where there are right-of-way restrictions or other constraints and as approved by the City Engineer.  Shared-Use paths shall have a minimum pavement cross-section of four inches (4”) of Hot Mix Asphalt Surface Course (placed in two lifts) upon six inches (6”) of compacted CA-6 subbase granular material placed upon a dry and compacted subgrade.  The subgrade and subbase shall be proof-rolled.

Paths shall be designed per the IDOT BLRS Manual and the Manual on Uniform Traffic Control Devices (MUTCD), latest editions.  Paths shall also meet the requirements of the ADA (Americans with Disabilities Act) and the Illinois Accessibility Code, where applicable.  Paths located in the right-of-way shall be designed and constructed according to Public Right-of-Way Accessibility Guidelines (PROWAG), or the current ADA guidance for facilities in the right-of-way.  Other design standards that should be used as needed are the IDOT BDE Manual, American Association of State Highway and Transportation Officials (AASHTO Guide for the Development of Bicycle Facilities, and National Association of City Transportation Officials (NACTO), latest edition.

9.  Drive Approaches

Where driveway incorporates curb, the connection to the existing roadway curb and gutter shall require a transition piece as detailed in Exhibit II-C-8.

Where private streets, drives, entrances, and alleys intersect public streets, the public street curb and gutter shall remain continuous across the access and depressed where needed.

The Contractor shall notify the City’s Engineering Division forty-eight (48) hours prior to placing the concrete to request an inspection of the base material and formwork.

All drive approaches shall be constructed to the following minimum standards.

  1. Residential
    1. Six inches (6”) of Class SI Portland Cement Concrete, non-reinforced with a continuous three-fourths inches (3/4”) full depth bituminous fiber material expansion joint at the sidewalk and at the back-of-curb. It shall be cured and protected as per the requirements for sidewalk.   Concrete shall be placed on a compacted stone or gravel base to a depth of four inches (4”) minimum.
    2. Asphalt driveways shall be three inches (3”) of Hot Mix Asphalt Surface Course upon eight inches (8”) of compacted CA-6 subbase granular material.
    3. All drive approaches shall be constructed with a depressed curb with an eighteen inch (18”) transition to the curb opening and shall have a flare of three feet (3’) at the street.  Existing curbs may be saw cut to form the depression. All drive approaches shall be constructed to a maximum grade within the right-of-way of six percent (6%).  In no case shall the algebraic difference of the drive grade and the street grade exceed eight percent (8%).  See Exhibit II-C-7.

OR

b.    Industrial and Commercial

  1. Eight inches (8”) of Class SI Portland Cement Concrete, non-reinforced with a continuous three-fourths inches (3/4”) full depth bituminous fiber material expansion joint at the sidewalk and at the back-of-curb (see Exhibit II-C-7). It shall be cured and protected as per the requirements for sidewalk.  Concrete shall be placed on a compacted stone or gravel base to a depth of four inches (4”) minimum.
  2. Asphalt is not an acceptable material for commercial or industrial drive approaches.

10.  Guardrail and Other Safety Measures

When it is necessary to provide protection against roadside obstacles or a non-traversable roadside hazard, the Design Engineer shall determine whether guardrail, raised curb, or some other safety measure is appropriate, based on the latest IDOT Design Manuals and other current guidelines.

11.  Traffic Regulatory Signs and Striping

All signs shall conform to the Federal Highway Administration “Manual on Uniform Traffic Control Devices for Streets and Highways”, latest edition, including the installation thereof.

For new development projects, the Developer shall be required to install regulatory signs pursuant to the approved engineering plans.

All posts shall be Uni-Strut, ten foot (10’), two inch (2”) square, fourteen (14) gauge in a V-Loc base, or approved equal.

Stop signs will be required where Collector streets intersect with Arterial streets and include a twenty four inch (24”) Stop Bar.

All striping shall follow IDOT District 1 Pavement Marking Standards and shall be Thermoplastic Pavement Markings, Type E (for asphalt) or Modified Urethane Pavement Markings (for concrete).  The cutoff date for placement of permanent pavement markings is November 1st; however, the City Engineer may approve a written request to allow placement of permanent pavement markings after the cutoff date.

12.  Street Name Signs

At each street intersection there shall be installed one or more street name signs showing the names of the streets.  The locations of street name signs shall be indicated on the construction plans.  Street name signs shall be installed by the Developer prior to issuance of building permits.

All Local street intersections shall have one street sign on the northeast corner.  Collector and Arterial streets shall have two (2) street signs, one on the northeast corner and one on the southwest corner of the intersection. For signalized intersections, the two (2) required signs shall be installed on the appropriate overhead mast arm per the applicable IDOT standard.  An exception will be made for a tee intersection where one sign would be required on the terminating street side of the intersection on the northeast corner thereof.  All street signs shall be set five feet (5’) back from the curb on the radius midpoint.   All street signs shall conform to the following specifications.

  1. All street signs shall conform to the Federal Highway Administration “Manual on Uniform Traffic Control Devices for Streets and Highways”, latest edition, including erection thereof.
  2. The flat aluminum blanks shall be 9” in height for Local, Collector, and Arterial streets.  The sign length may be twenty four inches (24”), thirty inches (30”), thirty six inches (36”), forty two inches (42”), or forty eight inches (48)” as determined by length of street name. Blanks shall have a one and one half inch (1.5”) radius at all corners. See Exhibit II-H-1.
  3. The blank faces shall be covered with 3M DG3 White Diamond Grade #4090. The letters shall be cut and removed from 3M Electrocut Green Film #1177C and then placed over the white film to produce white letters on a green background. See Exhibit II-H-1.
  4. Nine-inch (9”) high signs are covered on one side but two are required for each street. They are riveted to the sides of a twelve foot (12’) long, two inch (2”) square, fourteen (14) gauge Uni-Strut post in a V-Loc base, one per side for each street name with enough room at the top for a cap on the post.
  5. The street signs shall be in place prior to the issuance of any building permits.   Temporary street signs constructed of wood with neat lettering may be installed with seven foot (7’) clearance prior to the issuance of any building permit and must be removed immediately after the placement of the permanent street sign.

13.  Traffic Studies for Traffic Signals

In the case of anticipated installation of an all-way stop or traffic signals relating to a development, the Developer, at the request of the City Engineer and/or City Traffic Engineer, will be responsible for hiring a qualified traffic engineering consultant to conduct a traffic impact study.  The study will include, but is not limited to, a manual traffic count, existing and proposed average daily traffic (ADT) volumes for all involved roadways, and traffic control warrant analysis and justification.  If the City Engineer and/or City Traffic Engineer agrees with the warrant justification for traffic signal installation, an intersection design study with “Highway Capacity Manual” intersection analysis, will be required for review.

The manual traffic count may include pedestrian movements and/or accident data to justify meeting an acceptable warrant, as stated in the current edition of the Federal Highway Administration “Manual on Uniform Traffic Control Devices”.  The duration of the manual count must be a minimum of four hours including the A.M. and P.M. peak periods and could require up to twenty-four (24) hours to justify warrants.

14.  Traffic Signal Hardware

Traffic Signal Equipment shall comply with the applicable portions of the IDOT Standard Specifications for Road and Bridge Construction and IDOT Traffic Signal District One Special Provisions – Checklist and Use Guide, latest editions.

  1. Traffic Signal Post, Mast Arm Assembly and Pole
    Only galvanized steel painted black and powder coat finish, from an IDOT District One, Bureau of Traffic approved vendor or supplier will be used in the downtown Central Business District, as determined by the City Engineer.

    Other areas will be unpainted galvanized steel traffic signals and unpainted street lights as determined by the City Engineer.

    Wire mesh screening shall be installed between the top of concrete foundation for the mast arm and the base plate.  A mast arm shroud is not an acceptable alternate. 

    Combination mast arm assembly and pole may be required for intersection lighting, mounting video or radio detection, surveillance cameras, and/or radio antennae.
  2. Signal Heads and Pedestrian Heads
    All signal heads and pedestrian heads shall be LED.  Pedestrian signal heads shall have countdown timers and display.  
  3. Maintenance and Responsibility
    For the items “Maintenance of Existing Traffic Signal Installation” and “Temporary Traffic Signal Installation(s)”, the Contractor shall be responsible for placing stop signs for the intersection approaches, in the event of a power failure. The Contractor is also responsible for restoring the normal traffic signal sequence operation when power is restored. The Contractor shall respond to the emergency call from the City or others within one hour after notification.
  4. Electric Service Installation
    Overhead electric service cables shall enter a waterproof, sealed pathway consisting of a weather head, pole attached conduit, flexible conduit, to the pole mounted service cabinet.  All connections must be waterproof so no moisture and/or dust can enter the pole mounted service cabinet.  Conduit, containing ground cable from the service cabinet, shall extend to ground level, to prevent lawn maintenance from damaging the grounding cable.
  5. Traffic Actuated Controller
    All controllers shall be NTCIP compliant NEMA TS2 Type 1, Econolite Cobalt Type G Controller, or approved equivalent, and fully compatible and equipped for a fiber optic traffic interconnect, unless otherwise specified by the City Traffic Engineer.  Only controllers supplied by one of the IDOT District One approved closed loop equipment manufacturers will be allowed.  The controller shall be the most recent model and software version supplied by the manufacturer at the time of the approval and include the standard data key.  The traffic signal controller shall provide features to inhibit simultaneous display of a circular yellow ball and a yellow arrow display.  Individual load switches shall be provided for each vehicle, pedestrian, and right turn overlap phase.  The controller shall prevent phases from being skipped during program changes and after all preemption events.
  6. Controller Cabinet
    Grounding bushings must be used for all conduits entering the controller cabinet. Traffic signal cabinet must be NEMA TS2 meeting IDOT District One Special Provisions, from an IDOT District One approved manufacturer.
    1. Vehicle Detection System
      The vehicle/bicycle/pedestrian detection system shall be determined by the City Traffic Engineer and may include video, radar, in-pavement inductance loops, magnetometers or other technology from an approved IDOT District One or City approved vendor or supplier.
    2. Uninterruptable Power Supply/Battery Back-Up System (UPS/BBS)
      The UPS/BBS shall be provided by an approved IDOT District One or City approved vendor or supplier.
    3. Traffic Surveillance Video System 
      A pan-tilt-zoom camera shall be provided by an IDOT District One or City approved vendor or supplier.
    4. Ethernet Communication Equipment
      The City Traffic Engineer shall determine the software and hardware necessary to interconnect new traffic signals, such as: Ethernet switches, media converters/servers, Ethernet radios, and fiber optic interconnects.   All Ethernet communication equipment shall be provided by an approved IDOT District One or City approved vendor or supplier and must be compatible with City IT and Traffic Signal Central Networks.
    5. Illuminated Street Name Signs
      Illuminated street name signs shall be provided by an IDOT District One or City approved vendor or supplier.
    6. Emergency Vehicle Preemption System
      An Emergency Vehicle Preemption System shall include light detectors and confirmation beacons provided by an IDOT District One or City approved vendor or supplier and GTT 700 series phase selector/descriminator, or approved equal.

15.  Street Lighting

  1. General
    Unless otherwise specified by the City of Aurora, installation of street lighting shall conform to the National Electrical Codes and National Electrical Safety Code, most current edition.

    All street lighting plans shall be designed by an Illinois licensed Professional Engineer and included as a part of the final engineering plans.

    The City Traffic Engineer and/or the City’s Electrical Maintenance Supervisor shall receive catalog cuts for the streetlights and underground wiring for review and approval before the commencement of construction.

    The Developer and/or his engineer shall be held responsible for coordinating all phases of the work and correcting any deficiencies to the satisfaction of the City Traffic Engineer and the Electrical Maintenance Supervisor.

    In all installations, whether commercial or residential, when the feed goes to a ComEd pole, an appropriately sized and fused weatherproof disconnect shall be installed on the pole, eight feet (8’) above the ground.  One-inch (1”) diameter rigid conduit shall be used at the ground level.  Non-conductive PVC may be used above the disconnect, or may be provided by ComEd when applicable. The City is not responsible for any violations to ComEd standards by contractors. The Contractor is responsible for making necessary arrangements ahead of time with ComEd to ensure the connection meets their requirements.

    After the streetlight installation is complete, the Electrical Contractor or Developer shall provide the Electrical Maintenance Supervisor, or his designee, two (2) sets of as-built plans with lot numbers and street addresses.  A letter is required requesting inspection by the City’s Electrical Maintenance Division for ComEd to energize the streetlights.  The letter shall include all pertinent information, including but not limited to: electric load, wire size, lamp wattage, voltage, and number of lights to be energized.

    Locating the underground streetlight wiring shall be the sole responsibility of the Developer until the City Council formally accepts the streetlight improvements.

    Third Party Owners are responsible for all sections of these Specifications. The City of Aurora will only accept maintenance responsibility for streetlights upon final acceptance by the City Council.

    In the event that repairs and/or replacement of streetlights are not made to the City of Aurora’s satisfaction within thirty days of City notice, the City reserves the right to draw upon the posted Letter of Credit to pay a contractor and/or to reimburse the City for costs for such repairs.

    In all cases, the streetlights shall be installed prior to the issuance of any occupancy permits.

    If work is performed within IDOT right-of-way, the Contractor is required to be pre-certified with IDOT.

    Voltage drop shall be no greater than three percent (3%) from power supply to last unit with no wire size smaller than No. 6 AWG, Type RHH or RHW Underground Service Cable (USE) (XLPH).

  2. Power Supply Location and Connection
    The location and connections to a power supply shall be made to comply with ComEd Company rules and regulations, as amended from time to time.
  3. Street Lighting Controllers
    Streetlight controllers shall be manufactured by Excel Limited, or approved equal, using Square D lighting contactors, time delay relay, and circuit breakers. Twist lock photo cells shall be mounted on the control box.  Voltage networks will be 120/240 volt.  Where each fixture will have 120 volts, 240 volts is the maximum voltage allowed per light fixture in a non-residential area, unless authorized by the City Engineer and/or Electrical Maintenance Supervisor and shall be approved prior to any work permits being issued.  Residential areas are straight 120 volt only.  120/208 –3 phase lighting systems are applicable in the Central Business District where each fixture will have a 120-volt supply.  All street light controllers and control cabinets shall have electric meters.  The Contractor shall be responsible to install the meter socket and meter jumpers if applicable.
  4. Street Crossings
    Where a conduit crosses a roadway, a prefabricated Fibrelyte FL9 hand hole or approved equal will be installed on both sides of the roadway.  In no case will a conduit run be more than two hundred feet (200’) from pole to pole or from hand hole to pole on Arterial roads.
  5. Guarantee
    The manufacturer or distributor shall guarantee streetlight standards, luminaires, ballast, lamps, and cables for its proper use from one year after the date of acceptance.
  6. Installation for Local Residential and Minor Collector Streets
    1. Spacing
      Maximum spacing shall not exceed two hundred fifty feet (250’) between luminaires.  
    2. Location
      There shall be at least one streetlight on each intersection, curve, and cul-de-sac and the City of Aurora may require a streetlight to be placed at other points in special conditions.  They shall be located on the property lines and on the opposite side of the street from the water main, wherever possible, and shall be set two feet (2’) from the back-of-curb to the face-of-pole.  Installation of the required Collector/Arterial streetlight pole and luminaires may be required where residential or Minor Collector streets intersect with Major Collectors or Arterials.
    3. Light Distribution
      Luminaires of the Type III Distribution, as approved by the Illuminating Engineering Society (I.E.S.), shall be used in residential areas on straight sections of roadways.  Type IV distributions shall be used at intersections, curves and cul-de-sacs.  Luminaires of Type III or Type IV I.E.S. distribution shall be used in commercial areas. Intersections shall be I.E.S. Type V Distribution luminaires.
    4. Individual Control
      On individual control of lights, the photoelectric control shall be mounted on top of the luminaire.   The control of a group of lights shall be limited to one light fixture per one photo cell.  Therefore, multiple light fixtures shall not be connected in series to one photo cell.   Photo cells shall be Tork 2007 for 105/277 volt operation or approved equal.
    5. Conduit
      All streetlight cable crossings of commercial driveways, street and drive approaches shall have a minimum two inch (2”) rigid conduit sleeve that will encase the minimum one inch (1”) Uniduct.  Residential driveways and sidewalks only require the placement of the one-inch (1”) Uniduct. The Uniduct will be continuous from the source to the pole, or from pole to pole.  All exposed conduit transitioning to above grade shall be rigid conduit except where Uniduct enters the lower entrance on the streetlight pole.
    6. Underground Cable
      Only Schedule 40 Uniduct manufactured, high-density polyethylene, Type III, Grade P34 Class C material manufactured in accordance with NEC Article 343 for pre-assembled Cable in Duct, or approved equal may be used. Minimum one inch (1”) inside diameter PVC Uniduct conduit with direct burial No.6 minimum wire shall be used. All underground Uniduct containing underground cable shall be buried at least eighteen inches (18”) below the finished grade.  Direct burial cable without an approved raceway shall not be allowed in any installations, unless authorized by the City Traffic Engineer and/or the Electrical Maintenance Supervisor.
    7. Splices
      All Uniduct cable sections shall be continuous, and no wire splicing shall be made underground unless placed in a hand hole. Hand holes shall be Fibrelyte – FL9.  Splicing connections shall be made using T&B Method Crimp Sleeves, or approved equal, with T&B HSC Heat Shrink End Caps, or approved equal.
    8. Underground Cable Location
      Underground raceway shall be installed in a trench a minimum of two feet (2’) from the back-of-curb (away from the street) or one foot (1’) from either side of the sidewalk.  Cable shall not be installed directly underneath and along the length of the sidewalk without prior approval from the City Engineer and/or the Electrical Maintenance Supervisor.
    9. Fusing
      Underground feeders connected to an overhead electric service shall be fused at or below their rated capacity.  Each standard shall contain in-line fuse holders with proper fusing in series with each ungrounded conductor to protect the luminaire located on that pole.  All fuse holders shall be Bussman HEB-AA solderless fuse holders and shall be covered with rubber insulating boots.
    10. Streetlight Standard and Bracket
      Local and Minor Collector street poles shall be Ameron SEH-5.8 (212S) with SH-APD-4 Aluminum pipe arms or Stresscrete E250-APH-G-S35 C/W 184 H or approved equal.   Luminaire shall be mounted 19’-9” above the street, shall have a four foot (4’) arm and shall be buried a minimum of five feet (5’) below grade and backfilled with crushed CA-6 limestone watered and compacted around the butt of the pole.
    11. Luminaire
      All the luminaires shall be LED.  Luminaires for residential streets shall be GE ERL1-0-05-C3-40-A-Gray-R or approved equal. Catalog cut sheets shall be reviewed and approved by Electrical Maintenance Supervisor.

      Where non-standard poles and/or luminaires are approved, spare materials at no cost to the City may be required as a condition of approval.
  7. Installation for Arterial, Major Collector, and Commercial/Industrial Streets
    The below standards shall also apply at intersections with residential and Minor Collectors where standard street lighting does not currently exist on the Major Collector street or Arterial.
    1. Streetlight Standard Bracket on Arterial or Collector Streets
      The pole shall be manufactured by Millerbernd RHA8-400 arm or approved equal.  All poles shall be painted black per manufacturer’s requirements.

      Weathering steel is not permitted.

      The City of Aurora requires the use of transformer bases (TB5-9 or TB6-9) to match the bolt circles.  Bolts shall each be fitted with a flat washer and a lock washer.   Non-breakaway light pole supports may be considered at locations where pedestrians and bicycles may be prevalent.

      The pole will be designed to hold the luminaire arms as indicated on the plans in accordance with the latest edition of the “Standard Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals” as written by the American Association of State Highway and Transportation Officials.  The design wind velocity will be 80 MPH with a 1.3 gust factor.

      The light standard shall be designed for a wind velocity of 80 MPH and a gust velocity of 104 MPH. The pole design shall meet the latest edition of specifications for luminaire standards as published by AASHTO (American Association of State, Highway and Transportation Officials). A complete set of catalog cuts and drawings of the pole and luminaire shall be submitted.

      The pole shaft shall be fabricated from steel conforming to ASTM-A588 or A606.  The base plate shall be fabricated from steel conforming to ASTM-A588.  There will be a 4” x 6” reinforced hand hole one foot (1’) up from the base of the pole.  Pole sections shall be 11 GA.  Each pole shall be supplied with one (1) or two (2) lighting arms as required.   Lighting arms shall be attached with a two (2) bolt simplex bracket.  Never-Seez, or approved equal, shall be applied to all bolts. Lighting arms shall be six (6) sided, fabricated per the manufacturer’s specifications and as approved by the Electrical Maintenance Supervisor.  Each arm shall be provided with a 2” I.D. (2-3/8” O.D.) by 7-1/2” long tenon.  The luminaires shall be installed 8’0” from the pole.  The base plate will be 13-1/2” square, 3/4” thick with a minimum 5” diameter hole.  The base plate will have four (4) – 1-3/16” holes on 13-3/4” bolt circle to attach to the anchor bolt foundation.  Never-Seez, or approved equal, shall be applied to all bolts and each bolt shall be fitted with a flat washer and a lock washer.  All pipes shall be rigid, or approved equal.
    2. Grounding
      Each pole shall be connected to the ground by means of a copper wire of the #10 size and shall be welded to the inside wall of the pole and connected to a 5/8” diameter, eight foot (8’) long copper-clad steel ground rod.   The upper end of the ground rod shall be at least one foot (1’) below finished grade. The grounding of the streetlight fixture and arm shall be in accordance with the locally adopted electrical code.
    3. Foundations
      The foundations shall be concrete foundations, Type E, 24” as specified in the “Standard Specifications for Traffic Control Items” current edition as adopted by the State of Illinois Department of Transportation. Galvanized auger type foundations may be used with certain streetlight poles in special applications with approval from the City Traffic Engineer and/or Electrical Maintenance Supervisor.
    4. Luminaire
      The luminaires for Arterial, Major Collector and Commercial/Industrial streets shall be GE ERL2-0-18-C3-40-D-BLCK-AGIL. NOTE: fixtures that are operated by a controller require a photo cell receptacle with a shorting cap. A study may be required by the City Engineer to establish spacing. The standards for lighting levels shall be those recommended by the I.E.S. minimums and maximums.
    5. Group Control
      The control of a group of units shall be limited by the voltage drop calculations.  Street lighting along public streets in commercial, industrial developments and along Arterial streets shall be group controlled.
    6. Conduit
      All rigid galvanized conduits for placement under driveway aprons in non-residential areas and under residential streets shall be a minimum two inches (2”). All Uniduct will be a minimum of one inch (1”) diameter.
    7. Wire
      Underground cable shall be minimum #6 AWG, Type RHW, USE or XLPH and shall be installed in approved raceway from power supply to pole base and/or pole to pole without splices.  120-volt systems shall have 3 wires installed in the Uniduct (1 hot, 1 neutral and 1 ground).  Ground wire shall be either bare wire or insulated with green markings and can be one size smaller than current carrying conductor.  All systems shall contain a separate ground wire besides the current carrying conductors.  Where splices are allowed, a hand hole shall be installed. Hand holes shall be Fibrelyte – FL9.
    8. Wire (Pole and Bracket)
      Wire installed from the hand hole in the base of the pole to photo cell and luminaire shall be #10 AWG, type RHW, USE or XLPH.  The ground wire shall be at least #12 AWG.   Splicing connections shall be made using T&B Method Crimp Sleeves, or approved equal, with T&B HSC Heat Shrink End Caps, or approved equal.

16.  Street Parkway Landscaping

All parkways within the dedicated street right-of-way shall be graded with a minimum of six inches (6”) of pulverized topsoil and seeded, Class I minimum, or sodded in an approved manner.  The minimum gradient of all parkways toward the curb shall be two percent (2%) and the maximum shall be six percent (6 %).  If the parkway is constructed at a gradient of four percent (4%) or greater, then sod, jute mat, or excelsior blanket will be required.

Healthy and properly pruned street trees, having a trunk diameter measured twelve inches (12”) above the ground level of not less than two and one-half inches (2-1/2”) shall be planted along all streets at a rate of one (1) tree per lot with the exception of corner lots which shall have two (2) trees, one (1) on each street frontage.  For proposed industrial developments, the required trees shall be located on private property.

No tree shall be planted closer than fifty feet (50’) from any right-of-way intersection, closer than one hundred feet (100’) from any traffic control device, or closer than ten feet (10’) from a driveway or underground utility structure.

Approved tree species can be found at:

https://www.aurora-il.org/2051/Tree-Planting-Guidelines

Where an owner refuses in writing a tree from this list, that tree shall be planted instead at another location within the development so the total planted meets the requirements of the specification.

All landscaping within the right-of-way is to be in accordance with the Landscaping Plans duly processed by the Zoning & Planning Division and approved by the City Council.

Private irrigation systems are not allowed to be placed in the right-of-way unless a waiver of liability is submitted to the Engineering Division.  With the submittal of the waiver, the owner of the irrigation system acknowledges that the owner assumes all responsibility for location, relocation, maintenance and repairs if the system is damaged or needs to be relocated.

17.  Temporary Turn-Arounds

Temporary turn arounds, when required by Section 42-20(q) of the Subdivision Control Ordinance, City of Aurora, or the Fire Marshal, shall be constructed with the following specifications.

  1. The geometry of this temporary paving shall be a “T” configuration at the end of the street, which is paved from the inside of one sidewalk to the inside of the sidewalk on the opposite side of the street, fifteen feet (15’) wide with two (2) five foot (5’) radii to the street.  The curb and gutter shall not be constructed through the temporary turn around.
  2. The temporary turn-around shall be paved with eight inches (8”) of compacted crushed limestone base and two inches (2”) of asphalt surface course, without curb and gutter.
  3. The section of sidewalk through the temporary turn around shall be six inches (6”) thick.
  4. The Developer extending the street in the future shall remove the paving and base for the temporary turn-around, construct the curb and gutter so it is continuous and uninterrupted from one development to another development, and shall landscape the parkway, where disrupted by the asphalt and base removal.

18.  Half Streets

Half streets shall be prohibited, except where essential to the reasonable development of the subdivision, in conformity with the other requirements of these regulations and where the City Engineer finds it will be practicable to require the dedication of the other half when the adjoining property is subdivided.

Wherever an existing half street is adjacent to a tract for which subdivision is sought, the other half of the street shall be platted within the proposed subdivision.

The initial half street dedication shall be one-half (1/2) of the required right-of-way in width, with a ten foot (10’) parallel utility easement, and shall be of sufficient length to provide proper transitions with a minimum pavement width of twenty-two and one-half feet (22.5’) from centerline to the back of curb and of sufficient length to provide proper transitions.