Chapter 58. Article II. Addressing System of County Streets Secs Reserved. Article III. Streets Engineering Design Manual

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1 Chapter Article II. Addressing System of County Streets Secs Reserved. Article III. Streets Engineering Design Manual Sec Purpose. The purpose of this Article is to set standards for the construction of transportation facilities to serve new developments and for the reconstruction and maintenance of existing facilities. These standards shall apply to all improvements within existing and proposed rights-of-way and street easements. All projects shall meet all local, State, and Federal requirements. Sec. -. Applicability. This Article shall apply to public and private transportation facilities. Private streets, which includes easements, shall be held to the same standard as public streets. Sec. -. Financial Responsibility. Payment for any review, inspection, or certification required by an engineer or other professional shall be the responsibility of the party who has initiated the work. When an inspection, review, or certification is required to be done by a County engineer or other professional consultant contracted with the County, the party responsible for initiating the work shall reimburse the County the equivalent amount that is paid to the professional to complete the work. Sec. -. Street as a General Term. For the purpose of this Article, the term street is a general term that shall be used to describe any public or private transportation facility, including ingress/egress easements, but shall not include those facilities intended solely to access utilities, such as for electric power lines, gas lines, telephone lines, water lines, drainage facilities and sanitary sewers. Sec. -. Abbreviations. ADT = Average Daily Trips ASTM = American Society for Testing and Materials MUTCD = Manual on Uniform Traffic Control Devices FDOT = Florida Department of Transportation FHWA = Federal Highway Administration Florida Greenbook = Manual of Uniform Minimum Standards for Design, Construction and Maintenance for Streets and Highways //01 Draft Street Engineering Design Manual 1 of 1

2 IES = Illuminating Engineering Society NEC = National Electric Code NESC = National Electric Safety Code OSHA = Occupational Safety Health Administration IES = Illuminating Engineering Society Sec. -0. Street Names. Street names shall be approved as outlined in Article II of this Chapter. Sec. -1. Functional Classification. Functional classification shall be as described in the latest edition of the Florida Greenbook and the Guidelines for Geometric Design of Very Low-Volume Local Roads (ADT 00). Private streets shall be categorized according to the equivalent functional classification. Sec. -. Paving Requirements. A public or private street that serves as access to more than six lots and is designed or constructed after the adoption of this Article shall be paved. A public or private street that serves as access to six or less lots and is designed or constructed after the adoption of this Article may be unpaved but shall be built in accordance with the specifications for unpaved streets of Section - of this Article, as well as other applicable sections. Public or private streets that are currently unpaved are not required to be paved; however, the County may restrict development along such streets unless the street is paved and brought up to current engineering standards. Sec. -. Traffic Control Devices. All signs, markings and signals shall conform to the standards and guidelines of the latest edition of the MUTCD. The following specifications are to be followed when fabricating and installing traffic control devices in Glades County. (a) Sign Blank Materials (1) The sign blank shall be fabricated from aluminum sheet conforming to ASTM Specifications B0, with 0-H Alloy. () The sheet thickness shall be.00 inches. (b) Before any new street, detour, or temporary route opens for travel, all necessary signs shall be in place. (c) Regulatory, warning, and guide signs and object markers shall be retroreflective. Silk screening or Electro Cut material may be overlaid onto the sheeting. (d) Sign colors for private streets shall be blue and white. Sign colors for county streets shall be green and white. //01 Draft Street Engineering Design Manual of 1

3 (e) No letters are to touch or penetrate the borders of a sign. (f) All structural supports shall adhere to the latest edition of AASHTO s Standard Specifications for Structural Supports for Highway Signs, Luminaires and Traffic Signals, as modified by the FDOT Structures Manual, latest edition. (1) Sign Posts (a) Sign posts shall be designed to meet break-away standards. (b) Standard sign posts shall be 1 Gauge Square Galvanized Steel Posts Full Punch. (c) Posts are to be x square, unless a special type or decorative post is requested or specified in the plans. (d) All posts, except those installed in concrete medians, will be concreted in using a Hi Strength Concrete Mix which meets or exceeds ASTM C specifications. Each post hole shall have a minimum of 0 pounds to a maximum of 0 pounds of concrete mix added during sign installation. (e) Traffic signal installation shall also conform to the latest edition of the following codes and references: (1) Florida Department of Transportation Design Standards () Florida Department of Transportation Standard Specification for Road and Bridge Construction (most current) () Florida Department of Transportation Intersection Design Guide () Florida Department of Transportation Plans and Preparation Manual () Florida Department of Transportation Minimum Specifications for Traffic Control Signals and Devices. () NEC () NESC () OSHA Sec. -. Roadway and other Pathway Lighting. (a) All roadway lighting systems shall be designed using the latest edition of following codes and references: (1) Florida Department of Transportation Design Standards () Florida Department of Transportation Standard Specification for Road and Bridge Construction () Florida Department of Transportation Plans and Preparation Manual. () FHWA Guidelines for the Implementation of Reduced Lighting on Roadways. () FHWA Design Criteria for Adaptive Roadway Lighting. () Illuminating Engineering Society RP Lighting for Exterior Environments. () AASHTO s An Information Guide for Street Lighting. () Fundamentals of Traffic Engineering by the Institute of Transportation Engineers. //01 Draft Street Engineering Design Manual of 1

4 () NEC () NESC () OSHA (b) All pathway, walkway, and multi-use pathway lighting shall be designed using RP--1 Lighting for Exterior Environments, a publication by the IES. (c) All electrical components shall be UL approved and/or testing lab approved from labs accepted by the Florida Department of Transportation. (d) Service point location shall be verified by the designer with the applicable power company. (e) All roadway lighting shall be High Pressure Sodium unless otherwise approved by the County Manager. Sec. -. Street Design. (a) Design Speeds. The design speeds for all streets shall be in accordance with the Florida Greenbook, latest edition. (b) Pavement Widths. The minimum lane width for a local street and alley shall be feet. All other streets shall have a minimum lane width of 1 feet. (c) Shoulders. Minimum shoulder width is feet wide along the exterior sides of both outside travel lanes. Shoulders are not required to be paved along a local street or along an unpaved street, but all other streets shall have paved shoulders. (d) Streets shall be constructed using the Superpave mix design method, unless otherwise approved by the County Manager or as otherwise allowed by this Article. The acceptable superpave asphalt concrete mix type for structural use is SP-1. and the acceptable mix type for the wearing surface is SP-.. Reference FDOT Superpave Specification July 001 Supplemental Version. (e) Structural Cross Section. The required structural cross section of the various classifications of streets shall comply with the minimums shown in the table below. Road Classification Subgrade 1" *Base Group Structural Type SP-1. Wearing Surface SP-. Paved shoulder Same as abutting pavement Local and alley LBR 0 1." 1." Collector (Minor) LBR 0." 1." Collector (Major) LBR 0." 1." Arterial LBR 0." 1." * Base Group per FDOT Design standards (Latest Edition) (f) Horizontal & Vertical Alignment. All limits for both horizontal and vertical roadway alignments shall be in accordance with the Florida Greenbook, latest edition. //01 Draft Street Engineering Design Manual of 1

5 (g) Intersection Sight Obstruction Requirements. All intersections shall be designed to provide minimum unobstructed sight lines in accordance with the Florida Greenbook, latest edition. (h) Site Lines. (1) Where a centerline deflection angle of more than degrees occurs, a circular curve shall be introduced having a centerline radius adequate to ensure a sight distance of not less than the following: arterial streets 00 feet collector streets 00 feet local streets 0 feet alley feet () A tangent of not less than 0 feet shall be provided between reverse curves on all arterial and collector streets having radii less than 00 feet, unless unusual circumstances dictate alternate standards approved by the county engineer. () Street intersections shall be designed as follows: a. Streets shall intersect as nearly as possible at right angles and no street shall intersect at less than 0 degrees. b. A centerline offset of at least 1 feet shall be provided at street jogs offsets of less than 1 feet shall be prohibited. c. Intersections with an arterial or collector street shall be at least 00 feet apart measured from centerline to centerline. d. On any arterial or collector street, within feet of its intersection with another arterial or collector street, the dedicated right-of-way width shall be increased by ten feet on both sides to permit proper intersection design. () Minimum centerline grade for all streets shall be two-tenths percent. Maximum centerline grade shall not exceed the following: a. Arterial and collector streets: Five percent. b. Local streets: Eight percent. () Vertical alignment shall be such that the following requirements are met: a. Arterial and collector streets have a sight distance of at least 00 feet at four feet above ground level. b. Local streets have a sight distance of at least 00 feet at four feet above ground level. (i) Utility Accommodations. (1) Provisions should be made for planned utilities within the required rights-of-way or drainage/utility easements. //01 Draft Street Engineering Design Manual of 1

6 () As much as possible the water and overhead utility facilities shall be placed on the north and west sides of streets. Sewer and underground facilities shall be placed on the south and east sides of street. () Any facilities above ground shall be placed at the back of the right-of-way or easement lines. () Where feasible, underground utility mains and service connections shall be completely installed, inspected and approved by the county engineer after grading is completed and before the road base is applied (h) Pavement Width Transitions. Any change in pavement widths shall be designed with transitions that are in accordance with the Florida Greenbook, latest edition. (i) Medians. (1) Widths. All streets with greater than a single through-lane in each side direction shall be designed with a raised median separating the opposing lanes. Streets with a single lane in each direction may be designed with a raised median, but it is not a requirement. The minimum median width shall be in accordance with the Florida Greenbook, latest edition. () Openings. All median openings shall provide sufficient storage for the anticipated allowed movements of traffic. Median openings in residential areas shall be designed for Passenger Car P, Single Unit Truck SU, and Car & Boat Trailer P/B per the Florida Greenbook, latest edition. There shall be a minimum raised FDOT Traffic Separator provided between all left turn lanes and opposing traffic lanes. Sec. -. Alternative Street Design. Instead of using the guidelines in the Florida Greenbook, latest edition, and other requirements of this Article as applicable, the County may allow alternative guidelines to be used to design new or reconstruct and repair existing streets that are being used by or are projected to be used by a low volume of trips per day. The alternative guidelines are found in the FDOT Flexible Pavement Design Manual and the Guidelines for Geometric Design of Very Low-Volume Local Roads (ADT 00). Approval by the County must be gained prior to utilizing the alternative guidelines and such approval may only be granted after receipt and review of a transportation analysis performed by Professional Engineer licensed in the State of Florida. The type and number of vehicles using or projected to use the street will influence the approval by the County. If the alternative guidelines are used to construct the street, future access to the street by new development or changes in land use may be denied if such development or change in land use could cause the ADT to increase above 00. Sec. -. Street Ends. //01 Draft Street Engineering Design Manual of 1

7 Any street that does not terminate at an intersection is required to provide an adequate turnaround. The turn-around shall be constructed of the same material as the remainder of the street. (a) Cul-de-Sac. Any dead-end street terminating in a cul-de-sac shall be designed to allow the largest anticipated vehicle to safely turn-around without leaving the paved surface of the cul-de-sac, backing up, or executing a three point turn. In commercial and industrial developments, cul-de-sacs shall be designed to allow adequate turn-around space for semi-trailers. Residential cul-de-sacs shall be designed to allow turn-around space for the largest vehicle that may require access on that road, such as a fire truck or garbage truck. The dimensions will be determined by the Minimum Turning Path for the anticipated vehicle per the ASSHTO A Policy on Geometric Design of Highways and Streets, latest edition. The County Manager, or designee, shall determine what design vehicle is to the basis of the design. (b) Hammerhead turn-around. Only local dead-end roads with unavoidable physical restrictions that prohibit the standard cul-de-sac installation maybe allowed to terminate in a Hammerhead design, and only with the approval of the County Manager, or designee. The Hammerhead turn-around shall be designed to allow the anticipated vehicle to safely turn-around without leaving the paved surface of the cul-de-sac. Sec. -. Alleys. Alley intersections and sharp changes in alignment shall be avoided where possible, but where unavoidable, corners shall be cut off sufficiently to permit safe vehicular movement. Dead-end alleys are prohibited. Sec Trench Backfill and Restoration Any work within the county right-of-way must be permitted before work can commence. Open cutting of existing pavement is discouraged and will be allowed only on a case by case basis. If an open cut of an existing roadway surface is permitted, the excavation shall be restored to the pre-existing condition. Sec Grading All streets shall be graded so that pavements and sidewalks can be constructed to the required cross section. If special topographical conditions prevail, the county engineer may make exceptions provided they are basically consistent with the intent of these regulations. (a) Preparation. Before grading is started the entire right-of-way shall first be cleared of all stumps, roots, brush and other objectionable materials and all trees not intended for preservation. //01 Draft Street Engineering Design Manual of 1

8 (b) Cuts. All tree stumps, boulders and other obstructions and undesirable material shall be removed to a depth of one foot below the subgrade. (c) Fill. All suitable material from roadway cuts may be used in the construction of fills, approaches, or at other places as needed. Excess materials, including organic materials, soft clays, etc., shall be removed from the construction area. The fill shall be spread in layers not to exceed 1 inches loose and compacted by appropriate means to a density of no less than 0 percent of maximum density determined by the AASHTO Designation T-. The filling of utility trenches and other places not accessible to a roller shall be mechanically tamped, but where water is used to assist compaction, the water content shall not exceed the optimum of moisture without special exception. Sec Drainage and Swales. (a) A complete system shall be provided for handling drainage runoff. (b) The drainage systems shall be designed for long life, low maintenance cost, and upkeep by normal maintenance methods. (c) Swales and small ditches within the right-of-way shall have slopes not flatter than onethousandth of a foot per foot in the direction of flow. (1) Runoff may be accumulated and carried in the swales or ditches in the right-of-way along arterial streets up to but not above the point where flooding of the pavement or flooding of roadside property occurs; () Runoff may be accumulated and carried in the swale in the right-of-way along each side of a collector and local streets until the quantity is such as to result in a wetted area of ¾ square feet or until the quantity is such as to result in flooding of roadside property after ultimate completion of the street, whichever quantity is the least. Water in excess of these quantities shall not be carried in the streetside swales or ditches in the right-of-way, but shall instead be diverted therefrom and carried away in storm sewers, or in outfall ditches or by other approved means separate from the streets. (d) Allowable Flooding Depths. Allowable flooding depths based on street functional classification: (1) Local Streets and Alleys -year/-hour No flooding above the crown of road. -year/-hour Flooding not to exceed inches above the crown of street. 0-year/-hour Flooding not to exceed inches above the crown of street () Collector Streets Multilane collector roadways shall be designed and constructed to enable not less than one lane of traffic in each direction above the design high water elevation resulting from a -year frequency/-hour duration rainfall event. //01 Draft Street Engineering Design Manual of 1

9 year/ hour Flooding not to exceed inches () Arterial Streets No flooding up to and including the 0-year/-hour rainfall event. (e) All swales shall be sodded with grass sod capable of maintaining a healthy growth and shall be maintained in such condition by the property owner abutting or adjacent to the swale. No objects, structures, materials, plantings, or landscaping, other than grass sod, shall be placed, erected, installed, or located next to or in any swale with the following exceptions: (1) Traffic control devices such as signal lights, stop signs and yield signs; () Utility systems and appurtenant structures; () Drainage systems and appurtenant structures; () Sod or herbaceous ground cover; () Other plantings as may be permitted by the County Manager; () Low-profile, dome-shaped decorative button stones, blocks, or markers; () Underground sprinkler systems with flush or pop-up heads; () Mailboxes installed according to the requirements of the United State Postal Service. (f) Outfall ditches and other open channels shall be designed so they will not overflow their banks and if practicable they shall be designed for flow velocities that will not cause scour. Where higher velocities must be used, ditch pavement or other adequate permanent protection against scour shall be provided. (g) Drainage piping of all kinds shall be fitted with headwalls, endwalls, inlets or other appropriate terminating or intermediate structures. The design of headwalls, inlets, endwalls, catchbasins, manholes, ditch paving, box culverts, and minor drainage and related structures in general, shall follow current FDOT practices. Sec. -. Erosion Control This practice shall apply to all construction projects, regardless of size. Best Management Practices shall be consistent with current Florida Department of Transportation and Florida Department of Environmental Protection Design Standards. Applicable NPDES permit requirements shall be followed. Sec. -. Unpaved Streets (a) New unpaved streets: (1) Shall not exceed,0 feet in total length. () Shall have a minimum right-of-way width of 0 feet. A greater width may be required depending on requirements for drainage and other infrastructure. () Shall be cleared to a minimum width of 0 feet horizontal and 1 feet vertical for emergency vehicle access. The stabilized surface shall be a minimum of 0 feet. () Shall provide an entrance culvert of reinforced concrete pipe with mitered ends. //01 Draft Street Engineering Design Manual of 1

10 () Shall have a road name and other traffic signs installed in accordance with MUTCD signing and marking standards. () Shall have a stabilized turnaround at the end of the easement if the street is a dead end. The turnaround shall be a minimum of 0 feet in diameter with the stabilized roadbed being at least 0 feet in diameter. Other turnaround accommodations may be accepted by Glades County. () Follow the construction standards of Base Group I from Sheet 1 of FDOT Index Reference 1 for the road bed. The material chosen for the road base should exhibit low potential for losses due to wind, traffic and water erosion. EPA s publication AP- contains methodology for estimating the dust generation potential for unpaved road surfaces. Proper gradation of the chosen material is critical for its success. Designers shall consider flexible or rigid pavements where runoff from unpaved roads may impact surface waters. () Shall have be graded. Designers shall strive to provide adequate cross slope, shoulder and swale profiles. Typical cross slopes should be % with 1.% minimum. () Shall have a paved apron where the unpaved road connects with a paved road that shall meet the standards of Sheet of FDOT Index Reference 1. () Shall have drainage ditches along each side that shall have a minimum depth of feet. () Shall be maintained and made passable at all times. During maintenance grading, the operator shall ensure that the shoulder does not become higher than the travel lane edge to prevent ponding of water on the roadway. (b) Existing unpaved roads shall: (1) Meet the standards of new unpaved streets when improvements are made. () Maintain a limerock bearing ratio of 0. Sec. -. Construction Plan Preparation Any proposed construction within an existing or proposed right-of-way will require complete engineering plans, signed and sealed by a Professional Engineer licensed in the State of Florida. These plans shall include, at a minimum: (a) Cover Sheet (b) Plan and Profile sheets, drawn at a scale of no greater than 1 equals 0 scale. (c) Construction notes detailing instructions to the contractor (d) Drainage structure details (e) Erosion Control Plan (f) Cross sections of all proposed pavements (g) Restoration details of existing facilities //01 Draft Street Engineering Design Manual of 1

11 Sec. -. Variances The County Manager, or designee, will consider variance requests on an individual basis when there are circumstances which warrant an individual design due to geographic or topographic limitations of the site on which the facilities are to be constructed. In considering whether or not a variance should be granted, the County Manager shall consider the following factors: (a) The extent to which the proposed design meets other specific standards of this Article. (b) The extent to which the proposed design meets the spirit and intent of this Article through the use of materials, design criteria, and engineering, which will protect the health, safety, and general welfare of the public. (c) The positive or negative impact of the proposed design on surrounding property uses and property values, in comparison to the expected impact of the facilities if same were built in strict conformity with the standards of this Article. A variance shall not be granted to serve as a convenience to the applicant or for reasons related to economic hardship. Sec. -. Supervision required for private street construction. (a) Registered engineer to supervise. The work shall be constructed under the supervision of an engineer, hired by the person(s) building the street, who shall be authorized to require and who shall require that it be constructed in accordance with the construction plans and the requirements of this Article. (b) Measurements and tests required. During construction, the engineer shall cause to be made such field and laboratory tests as are needed to assure that the work and materials conform to the development plan and the requirements of this chapter. The results of these tests shall be submitted to the County s engineer. (c) Inspection by County s engineer. The County may require a licensed engineer to make such inspections on behalf of the county as may be needed before, during and after the construction of the work, to keep informed of the status of the development, and to generally assist all agencies involved in the work in maintaining the standards of this chapter. (d) Completion certificate. On completion of the work, the engineer shall furnish the County Manager with a certificate stating that the work has been entirely completed, that it was constructed under the engineer's supervision, and that it conforms to the construction plans and the requirements of this Article. (e) Final project records. Accompanying the completion certificate required by subsection (d) of this section, the engineer shall also furnish the following: (1) One white print and one ammonia transparency of the construction plans, corrected to show the work and other facilities in the rights-of-way and drainage easements as actually built. //01 Draft Street Engineering Design Manual of 1

12 () A copy of the results of the measurements and tests made on the work and materials to ensure that they complied with the construction plans and the County's requirements. (f) Completion certificate and final project records required. The work shall not be considered complete until the completion certificate and the final project records called for in subsections (d) and (e) of this section have been furnished. Until such items have been furnished and approved, the street shall remain closed to vehicular use. //01 Draft Street Engineering Design Manual 1 of 1