(A) General. The arrangement, character, extent, width, grade and location of all streets to be dedicated to the public, all parking lots and all private streets shall be compatible and complimentary to existing and planned streets, to reasonable circulation of traffic within any subdivision and adjoining lands, to topographical conditions, to runoff of storm water, to public convenience and safety, and in their relations to the proposed uses of the area to be served. All traffic intersections and confluences shall encourage safe and efficient traffic flow.
(B) Design references. All pavements shall be designed and constructed in accordance with the following references as they apply:
(1) “Standard Specifications for Road and Bridge Construction,” latest edition, published by the Illinois Department of Transportation.
(2) “Supplemental Specifications and Recurring Special Provisions,” latest edition, published by the Illinois Department of Transportation.
(3) “Bureau of Local Roads and Streets Manual,” latest edition, published by the Illinois Department of Transportation.
(4) “Bureau of Design and Environment Manual,” latest edition, published by the Illinois Department of Transportation.
(5) “Drainage Manual,” latest edition, published by the Illinois Department of Transportation.
(C) Pavement design requirements.
(1) Pavement design shall relate to the street classification at the direction of the Director of Public Works and Engineering. The proposed roads indicated on the official map are desired to be eventually constructed, but their actual alignment will be decided upon when the preliminary plan is submitted to the Plan and Zoning Commission and the corporate authorities for review and approval.
(2) The classification of new streets, as well as variations to street classifications for a given street, shall be submitted to the Director of Public Works and Engineering or authorized designee for his/her review with the submittal of the “Preliminary Plan.”
(D) Pavement design. All new streets, public or private, shall be improved and constructed with pavement complying with the requirements of this chapter and as follows:
(1) Subgrade. All subgrade material shall have a minimum Illinois Bearing Ratio (IBR) of 3.0. All unsuitable subgrade material, including subgrade material having an IBR less than 3.0, shall be removed and replaced with suitable fill material, or the pavement shall be designed to compensate for the soil condition. The soil support IBR values selected for use by the design engineer shall represent a minimum value for the soil to be used.
(2) Pavement design. The pavement design standards denoted in the following table of pavement and right-of-way width shall be adhered to. A copy of all design assumptions and computations on which the proposed pavement design is based shall be submitted to the Director of Public Works and Engineering or authorized designee.
TABLE OF PAVEMENT DESIGN AND RIGHT-OF-WAY WIDTH | ||
Classification | Minimum right-of-way width | Minimum roadway width (e/p to e/p) |
TABLE OF PAVEMENT DESIGN AND RIGHT-OF-WAY WIDTH | ||
Classification | Minimum right-of-way width | Minimum roadway width (e/p to e/p) |
Arterial | 120 feet | 48 feet |
Minor Arterial | 100 feet | 48 feet |
Collector | 80 feet | 34 feet |
Local (residential)* | ||
1. Dedicated | 66 feet | 28 feet |
2. Private | 28 feet | |
Industrial* | 100 feet | 36 feet |
Frontage Road | 50 feet | 27 feet |
* The pavement diameter of cul-de-sac turnarounds shall be 87 feet (b/c to b/c). The right-of-way diameter of a cul-de-sac turnaround shall be 120 feet. | ||
The minimum pavement width in an estate residential zoning district shall be 22 feet.
All street pavements shall have a 2.0% cross slope, so the height of the pavement crown will be dependent on the pavement width.
(3) Grades.
(a) Roadway profile grades shall not exceed 5% on collector streets, nor 7% on other streets, unless approved by the Director of Public Works and Engineering or authorized designee. Roadway profile grades shall not be less than 0.5% on tangent sections.
(b) The minimum length of vertical curves shall be 100 feet for one and 1.5% difference of grade. For each additional 1% difference in grade over one and 1.5%, a 50 foot increment shall be added to the length of a vertical curve. If the grade differential is less than 1.5%, a vertical curve is not required.
(4) Sight distances. At the points of intersection of proposed roads with existing roads, the minimum stopping sight distance shall be calculated in accordance with Chapter 28 of IDOT's Bureau of Local Roads and Streets Manual.
(5) Curb and gutter.
(a) Combination curb and gutter shall be constructed on both sides of all street pavements and shall comply with the requirements of the City of Lockport standard drawings, except for development in the E-R Estate Residential Zoning district, where curb and gutter will be required at intersections with arterial streets and at other such locations required by the corporate authorities. In those locations where curb and gutter is not required, the pavement base course shall be extended an additional two feet beyond the finished pavement width.
(b) Two No. 4 reinforcing bars shall be placed continuously along the curb. Expansion joints shall be doweled and spaced no more than 60 feet on center and at tangent points of all radii. Control joints shall be provided at 15 feet on center and shall consist of a saw cut at least one and 1.5 inches deep.
(c) Unless otherwise directed by the Director of Public Works and Engineering or authorized designee and pursuant to IDOT standards, a barrier curb and gutter (B-6.12, B-6.18 or B-6.24) shall be provided on all arterial and collector streets. Gutter widths shall be determined by inlet spacing to permit no more than three feet of encroachment on the pavement due to runoff from the 10% annual probability (ten-year) storm.
(d) For all barrier curb and gutter and six inch mountable curb and gutter, depressed curb shall be provided at all driveways. For all curb and gutter, depressed curb shall be provided at all sidewalk crossings in accordance the Illinois Accessibility Code (IAC) and Americans with Disabilities Act (ADA) requirements.
The subgrade of all paved areas shall be prepared in accordance with of Section 301 of Standard Specifications for Road and Bridge Construction.
Sub-Base Granular Material, Type B shall be meet the requirements of Section 311.
Aggregate Base Course, Type B shall meet the requirements of Section 351.
Hot-Mix Asphalt Base Course shall meet the requirements of Section 355.
Portland Cement Concrete Base Course shall meet the requirements of Section 353.
Hot-Mix Asphalt Binder Course shall meet the requirements of Section 406.
Hot-Mix Asphalt Binder Course shall meet the requirements of Section 406.
Portland Cement Concrete Pavement shall meet the requirements of Section 420.
(E) Inspections and testing.
(1) At least one standard proctor density test, performed in accordance with AASHTO T99, shall be taken in each embankment section, with the maximum distance between tests of 300 feet. One standard proctor density test shall be taken from each different source of borrowed material. The results of the density tests must be submitted to the Director of Public Works and Engineering or authorized designee. Upon review of these tests, an inspection of the subgrade by proof-roll with a fully-loaded truck shall be made by the Director of Public Works and Engineering or authorized designee. A report of acceptable subgrade and preparation shall be submitted to the Director of Public Works and Engineering or authorized designee prior to placing curb and gutter, sub-base or base course.
(2) Hot-mix asphalt shall be placed when the ambient temperature is at least 40° F and rising for binder course and at least 45° F and rising for surface course, on a clean, dry base, when rain is not in the forecast. Placement of hot-mix asphalt after November 1 shall require written authorization from the Director of Public Works and Engineering or authorized designee. This authorization will not in any way negate the contractor and developer guarantee on the work performed. Cold joints shall be avoided to the maximum extent possible.
(3) After flexible pavement base and binder courses have been in place for at least nine months, including a winter and a spring, one pavement core for every 900 lineal feet of measured pavement shall be taken. A commercial testing laboratory shall prepare a report listing thicknesses of all pavement courses, the density of all hot-mix asphalt courses and the type and condition of the subgrade, as determined from laboratory testing of the cores. The report shall be submitted to the Director of Public Works and Engineering or authorized designee and if the results of the cores indicate pavement deficiencies, additional cores will be required as directed by the Director of Public Works and Engineering or authorized designee. Upon receipt of the report, the Director of Public Works and Engineering or authorized designee will review said report and will perform an inspection of the existing pavement. All base and binder course failures will then be repaired to the Director of Public Works and Engineering or authorized designee's satisfaction before installation of the hot-mix asphalt surface course.
(F) Maintenance and responsibility.
(1) The maintenance and responsibility for private roadways shall be the responsibility of the developer until the final maintenance bond is released, when the owners' or homeowners' association shall become responsible for maintenance.
(2) All streets, curbs and gutters to be dedicated to the city shall be under warranty for any and all defects and failures in either the surface course or underlying courses or subgrade for a period of one year after the start of the maintenance period.
(Ord. 18-008, passed 2-7-18; Am. Ord. 21-021, passed 8-18-21)