§ 158.027 STREET IMPROVEMENTS.
   (A)   Design.
      (1)   General standards.
         (a)   Streets shall be designed and located in relation to existing and planned streets, to topographical conditions and natural terrain features such as streams and existing tree growth, to public convenience and safety, and in appropriate relation to the proposed uses of land to be served by such streets.
         (b)   All streets shall be properly integrated with the existing and proposed system of thoroughfares and dedicated rights-of-way as established by the village.
         (c)   All thoroughfares shall be properly related to special traffic generators, such as industries, business districts, schools, churches and shopping centers, to population densities and to the pattern of existing and proposed land uses.
         (d)   Minor streets shall be laid out to conform as much as possible to the topography, to discourage use by through traffic, to encourage efficient drainage and utility systems, and to require the minimum number of streets necessary to provide convenient, safe access to property.
         (e)   It is the intent that the street system, whether public or private, to encourage safe and efficient traffic flow and provide safe vehicular storage space for stopping and turning movements so as not to conflict at intersecting streets or driveway entrances.
         (f)   Proposed streets shall be extended to the boundary lines of the parcel to be subdivided, unless prevented by topography or other physical conditions, or unless in the opinion of the Planning and Zoning Commission, extension is not necessary or desirable for the coordination of the layout of the subdivision site plan with the existing layout or the most advantageous future development of adjacent parcels.
         (g)   In business and industrial developments, the streets and other accessways shall be planned in connection with the grouping of buildings, location of rail facilities, and the provision of alleys, truck loading and maneuvering areas so as to minimize conflict of movement between the various types of traffic.
         (h)   Dual access shall be provided in any subdivision site plan beginning with the initial construction and shall be maintained in suitable condition for passage of private and emergency vehicles.
         (i)   Where a subdivision borders on or contains a railroad or highway, the Planning and Zoning Commission may require a street approximately parallel to and on each side of such railroad or highway, at a distance suitable for the appropriate use of the intervening land, for park purposes in residential districts or for commercial or industrial purposes in appropriate districts. Such distances shall also be determined with due regard for the requirements of approach grades and future grade separations.
         (j)   Where a subdivision abuts or contains an existing or proposed highway or major thoroughfare, the Development Review Committee may require marginal access streets, reverse-frontage with screen planting contained in a non-access reservation, at least ten feet wide, along the property line; deep lots with rear service alleys; or such other treatment as may be necessary for adequate protection of residential properties and to afford separation of through and local traffic.
         (k)   Developments shall be designed so that the developer/subdivider provides not less than one-half of the right-of-way dedication required for an exterior street.
      (2)   Design criteria.
         (a)   Tangent sections (measured from ROW of intersecting street):
            1.   Tangents (minimum length 100 feet) shall be introduced between horizontal reverse curves on all streets; and
            2.   Tangents (minimum length 50 feet) shall be introduced at the end of all curvilinear roads at intersections.
         (b)   Cul-de-sac and U-streets:
            1.   The use of u-shaped streets is not encouraged.
            2.   The length of a cul-de-sac street shall not exceed 750 feet in length as measured along the center line of the cul-de-sac street from the centerline of the start of the origin to the end of the right-of-way.
            3.    Cul-de-sac terminus shall have a minimum pavement diameter measured 80 feet edge-to-edge in areas zoned residential, and 100 feet in all other areas.
         (c)   Streets shall be laid out so as to intersect as nearly as possible to right angles and no new street shall intersect any existing street at less than 80 degrees nor more than 100 degrees. No more than two streets shall intersect at any one point unless specifically approved by the Development Review Committee.
         (d)   Horizontal curves:
            1.    Horizontal curves are required where the angle of deflection in horizontal center lines exceeds five degrees. The radius of the horizontal center line curve shall not be less than the following dimensions depending on the classification of the street involved:
               a.    Major street, 500 feet.
               b.    Collector street, 300 feet.
               c.    Minor street, 100 feet.
               d.   Any variance must demonstrate that the curve has a radius adequate to ensure clear sight distances.
         (e)   Vertical curves. Vertical curves shall be used whenever the algebraic difference in centerline gradients exceed 1%. The length of the vertical curve shall be established on the basis of design speed and stopping distance in accordance with "A Policy on Geometric Design of Highways and Streets" (AASHTO, latest edition).
         (f)   Street grades.
            1.   Grades shall provide proper relation between the street and the first floor elevation of the houses or buildings to permit convenient and economical access to and drainage of the lots.
            2.   All streets shall be graded to their full width, including side slopes and the sub-grade of the areas to be paved.
            3.   Street gradients shall be as specified in Appendix A: Table A-1: Street Design Guidelines.
            4.    Residential driveway slopes shall be between 2% and 8%.
         (g)   Intersection design.
            1.   All intersections (street-to-street and driveway-to-street) should encourage safe traffic flow.
            2.   Streets and driveways shall be located to avoid centerline offsets between other streets and driveways of at least the following minimum dimensions:
               a.    Driveway-to-driveway: 100 feet;
               b.    Driveway-to-local: 125 feet;
               c.    Local-to-local: 125 feet;
               d.    Driveway-to-collector: 125 feet;
               e.    Local-to-collector: 150 feet;
               f.    Collector-to- collector: 200 feet;
               g.   If requested, a traffic study will be prepared to determine the required length of storage or stacking and the minimum dimension shall be such that the driveway (full-access) will not be located in the storage or taper. Right-in/right-out access can be closer to an intersection with village approval.
               h.    Residential driveway-to-residential driveway - maximized to the extent possible.
            3.   Curb radii. Minimum curb return radii shall be measured from the center to the back of curb, and shall conform to the following:
               a.    Major/major: 30 feet radius.
               b.    Major/boulevard: 30 feet radius.
               c.    Major/collector: 30 feet radius.
               d.    Major/local: 25 feet radius.
               e.    Boulevard/boulevard: 30 feet radius.
               f.    Boulevard/collector: 30 feet radius.
               g.    Boulevard/local: 25 feet radius.
               h.    Collector/collector: 30 feet radius.
               i.    Collector/local: 25 feet radius.
               j.    Local/local: 25 feet radius.
               k.    Minimum internal roadway (commercial/industrial) radius: 25 feet.
         (h)   Alleys.
            1.   Alleys may be required in commercial, business and industrial districts, except where definite and assured provisions are made for service access, such as off-street loading, unloading and parking, consistent with and adequate for the uses proposed and in accordance with the provisions of the Zoning Ordinance.
            2.   Alleys in residential areas shall not be permitted, except where approved and recommended by the Development Review Committee.
            3.   The width of alleys shall not be less than 20 feet.
            4.   Alley intersections and sharp changes in alley alignment shall be avoided, but where necessary, corners may be cut off sufficiently to permit safe vehicular movement.
            5.   Dead-end alleys are prohibited.
            6.   Alley pavement shall conform to the construction standards set forth in this section.
         (i)   Traffic calming and control devices. The village may, at its discretion, require the use of roundabouts or other traffic-control devices in the design of roadways within a subdivision. Costs for traffic calming and control devices shall be included in the applicant's letter of credit.
   (B)   Right-of-way dedication.
      (1)   All street and roadways proposed within the confines of a subdivision shall be located in dedicated public rights-of-way. Street right-of-way widths shall be as specified in Appendix A; Table A-1: Street Design Guidelines.
      (2)   Where streets define the separation of two or more zoning districts, right-of-way dedication shall be provided so as to meet the requirement of the zoning district requiring the larger right-of-way.
      (3)   A private roadway system may only be contemplated in situations where there is adherence to the following standards:
         (a)   The private roadways must be integral to the development in question. Private roadways may not connect to adjacent developments.
         (b)   Appropriate easements, both for utilities and future roadway widening, if necessary, must be included in the design.
         (c)   Appropriate setbacks, both for buildings and for parking must be included in the design. At a minimum, the setbacks must be equivalent to the zoning district setbacks measured from the curb line, but not less than the width of easements.
         (d)   The design of the private roads must meet the criteria of this chapter.
      (4)   Each cul-de-sac street shall terminate with a circular area having a minimum right-of-way diameter of 110 feet in residential areas and 120 feet in all other areas.
      (5)   Reserve strips (sometimes called "spite" strips) controlling access to public utilities or streets shall be prohibited.
   (C)   Construction standards. The standards and specifications contained within this chapter may be modified, amended, or amplified by the Director of Public Works. Such modifications, amendments, and amplifications are available at the Public Works Department.
      (1)   Street improvements shall be provided in each new subdivision site plan in accordance with the regulations set forth in this section and the tables of minimum standards and typical section as set forth as Appendices A and B, respectively. The regulations for street improvements are as follows:
         (a)   All streets in single-family residential zoning areas shall be constructed in accordance with this chapter.
         (b)   All streets in multi-family and commercial zoning areas shall be constructed in accordance with minor collector standards.
         (c)   For industrial and other special use areas as determined by the Planning and Zoning Commission and the Village Engineer.
         (d)   All street construction, including the items listed above, shall conform to the requirements of the Illinois Department of Transportation Standard Specifications for Road and Bridge Construction, adopted January 1, 2007 and amended from time to time.
      (2)   All unsuitable sub-base material shall be removed and shall be replaced with stable, compacted material in conformance with generally accepted engineering practices. Soil test reports are to be submitted to the Village Engineer at the time of plan submittal. Sub-grade stability improvements will be required for soils with an IBR less than 4.0. Lime stabilization may be utilized but must be in accordance with IDOT Sections 302 and 310 and be approved, in writing, by the Director of Pubic Works.
      (3)   All pavement thicknesses, including surface, base courses and sub-base courses, shall be designed in accordance with the Illinois Department of Transportation standards. The minimum thicknesses for Class IV streets (as designated in IDOT's Bureau of Design and Environmental Manual) shall be as specified in Appendix B: Roadway Specifications. Proof roll of the sub-base and base course shall be conducted and densities of the subbase, base course, binder course and surface course of all streets shall be field-verified during construction with nuclear methods by a developer employed testing service.
      (4)   Class III streets (as designated in IDOT's Bureau of Design and Environmental Manual) require design data to be submitted to the Village Engineer at the time of plan submittal and shall always meet or exceed the minimum requirements in Appendix B: Roadway Specifications. However, alternate materials may be considered by the Planning and Zoning Commission, if recommended by the Village Engineer, if structurally equal.
      (5)   Curbs and gutters.
         (a)   Curb and gutter shall be constructed on all streets and shall be combination (integral) concrete. Curbs may be constructed integrally with the Portland Cement concrete pavement. All curbs and gutters shall be installed in accordance with the minimum standards and specifications as contained in Appendix A: Table A-1: Street Design Guidelines or as approved by the Village Board after recommendation by the Planning and Zoning Commission.
         (b)   Curb and gutter shall be Type B-6.12 unless otherwise noted in Appendix A: Table A-1: Street Design Guidelines or as required by the Village Engineer for wider pavement widths.
         (c)   All curb shall be designed with a minimum slope of 0.5% unless otherwise approved by the Village Engineer.
         (d)   Curb ramps shall be designed in accordance with all federal, state, and local guidelines with respect to accessibility. At a minimum, ICC/ANSI AI17.1 - latest edition and the Illinois Accessibility Code should be used during design. Then current IDOT standard details for curb ramps shall be included on design plans.
         (e)   Curb and gutter poured next to concrete pavements shall be done in accordance with then current IDOT details.
      (6)   Street signs. The developer will pay for all street name and regulatory signs. All signs will be installed by the developer in accordance with the Manual on Uniform Traffic Control Devices and consistent with the Traffic Control Plan. The cost of all signage is to be included in the letter of credit. All signs are to be installed within one week of the construction of the roadway bituminous binder. The signs shall meet the following requirements:
         (a)   A sign plan is required as part of the development plans and must be approved by the Village Board and Police Department before signs are to be installed.
         (b)   Sign supports shall be two pounds U-channel galvanized posts with ground sleeves cut four feet; cut to height.
         (c)   Stop sign - 30 inch diamond grade V.I.P. stop sign-local streets (reflective).
         (d)   Stop sign - 36 inch diamond grade V.I.P. stop sign-collector/arterial streets (reflective).
         (e)   Speed limit sign - 24" x 30" diamond grade V.I.P. -25 MPH on local streets (see attached).
         (f)   Speed limit sign - 24" x 36" diamond grade V.I.P. collector/arterial (see attached).
         (g)   Twenty-five mph and under - green on both sides - residential street name signs green with four inch white letters - six inch Extruded Blade (letters to be reflective) high intensity sheeting (18" Minimum Blade).
         (h)   Over 25 mph - 080 covered blank; green on both sides; collector streets and greater six inch white letters - nine inch (letters to be reflective) high intensity sheeting (18" Minimum Blade).
      (7)   Striping.
         (a)   The developer will pay for all stripage. All stripage will be installed by the developer in accordance with the Manual on Uniform Traffic Control Devices and consistent with the Traffic Control Plan. The cost of all stripage is to be included in the letter of credit. All stripage are to be installed within one week of the construction of the roadway bituminous surface.
         (b)   Raised reflective pavement markers shall be required only where deemed necessary by the Director of Public Works on centerline skip dash, double yellow centerline turn lanes.
         (c)   Stop bars shall be 24 inches wide and required at all stop sign locations.
         (d)   Crosswalks shall have six inch wide lines at intersections, 12 inch wide bars at school crossings.
         (e)   All permanent striping shall be thermoplastic.
         (f)   Temporary paint striping shall be required after binder placement on all collector streets or where deemed necessary by the Director of Public Works.
      (8)   Restrictions on building permits:
         (a)   Prior to the issuance of a building permit, the roadway bituminous binder course must be installed up to the front of the principal structure for which the permit has been applied.
         (b)   Prior to the issuance of an occupancy permit, the subdivided lot shall have a driveway paved with an asphalt and/or concrete surface minimally extending from the adjacent public street to the front setback line of the principal structure located on the lot. If weather conditions or other circumstances beyond the developer's control prevent installation of all or portions of the driveway and all other requirements for the issuance of a certificate of occupancy have been met, a letter of credit or a performance guarantee approved by the Village Attorney to ensure completion of approved driveway shall be filed with the Village Manager. The amount of the performance guarantee and the required completion data shall be recommended by the Zoning Administrator based on current costs and set by the Village Board.
      (9)   Partially completed streets. In the event that a development is planned for initial construction with a binder course only, with the surface course to follow upon completion of the development, the following criteria shall apply.
         (a)   Binder wedges are required along the edge of all public roads where the binder is to be exposed for more than six months.
         (b)   The surface layer is to be placed based on the criteria in this division (C).
         (c)   Wedges are required around all manholes.
(Ord. 2313-95, passed 2-1-95; Am. Ord. 07-0541, passed 6-6-07; Am. Ord. 12-1014, passed 11-7-12)