§ 3-6-24. Roadway construction standards.

In the interest of public safety and to ensure safe, uniform construction of roadway improvements throughout the county, all construction undertaken to widen existing roadways or to provide turn lanes, acceleration lanes or deceleration lanes shall be accomplished in accordance with the following standards and criteria:

(1)

Base and subgrade:

a.

Base materials shall be of the same type as the base materials of the existing, adjoining roadway.

b.

All base materials shall be placed on a stabilized subgrade, minimum seventy (70) LBR. Tests will be made at the rate of one (1) per section, or every one hundred (100) feet, whichever is more restrictive, and shall be signed by a professional engineer registered in the State of Florida. The cost for all testing shall be borne by the developer, contractor.

c.

Flexible base materials (limerock, shell) shall be from a state department of transportation approved source for this type material.

1.

Limerock or shell base shall be compacted to a minimum nine-inch depth and brought to a finish grade minus two and one-half (2½) inches. Compaction shall be in accordance with AASHTO-T180.

2.

Prime coat shall be applied in accordance with the 1986 edition of the Florida Department of Transportation Standards for Road and Bridge Construction, Section 300, at a minimum rate of 0.15 gallons per square yard.

(2)

Alternate base groups:

a.

Asphalt base courses may be used adjoining existing flexible base roadways only. Depth of this material shall be sufficient to equal or exceed a structural number value of 1.70, as established by the state department of transportation.

1.

Asphaltic base course shall be applied in accordance with the Florida Department of Transportation Standards for Road and Bridge Construction, Section 280.

2.

Asphaltic base courses shall be brought to finish grade, minus one (1) inch.

b.

Rigid base materials shall be used adjoining existing rigid base roadways only, and may be either soil cement mixed in place (minimum three hundred (300) PSI at seven (7) days), plant mixed soil cement, econocrete, or concrete. Depth of this material shall be sufficient to equal or exceed a structural number value 1.70, as established by the state department of transportation.

1.

Rigid base construction shall be performed in accordance with the Florida Department of Transportation Standards for Road and Bridge Construction, Sections 270, 345 or 350, as applicable.

2.

Rigid base course shall be brought to finish grade, minus one (1) inch.

(3)

Paving:

a.

Paving shall be performed with Type III asphaltic concrete, in accordance with the Florida Department of Transportation Standards for Road and Bridge Construction, Sections 330 and 333.

b.

Paving over flexible base construction shall be performed prior to pavement overlay and shall consist of the placement of a minimum of one and one-half-inch Type III asphaltic concrete, brought to finish grade, minus one (1) inch.

c.

Overlay of the entire roadway, including existing roadway and all widening, shall be performed with the application of one-inch Type III asphaltic concrete, resulting in a uniform slope of one-quarter-inch per foot from the crown to the outside edges of pavement.

(4)

Sidewalks/Bike Facilities: It is the expressed policy of the board of county commissioners that sidewalks and bike facilities are an integral part of the county's transportation system. Therefore, all site development projects located on arterials and collector roadways will be required to install sidewalks and bike facilities as part of any site development plan. If there are cases where connectivity of a sidewalk or bike network requires that adequate facilities be provided along the frontage of a roadway classified as local or residential, the county engineer may require that these facilities be provided. The requirements of this section may be waived by the county engineer for developments of four (4) standard size building lots or less, or if the county engineer determines that a sidewalk or bike facility is not required because adequate facilities already exist.

a.

Standards and Specifications: Sidewalks will be designed to meet or exceed current FDOT and county standards w/respect to the base preparation, slab thickness, joint locations, finish, drainage, and all other applicable specifications. All designs and installations will meet or exceed the Americans With Disabilities Act (ADA) specifications and guidelines. The minimum sidewalk width shall be eight (8) feet, except for those cases where state law may require a different width.

b.

Exception and Modification: It is recognized that there will be situations that exist which affect the ability of a developer to comply with the requirements of this section. Therefore, the county engineer may alter or delete the requirements of this section if, in the determination of the county engineer, some physical or topographical feature prevents or seriously restricts the capability for the sidewalk or bike facility to be included with the project.

(Ord. No. 88-24, § 1, 7-26-88; Ord. No. 07-018, § 1, 4-24-07)