§ 6.04.04. Design Standards

A.

Driveway Width/Length

Driveways provide the physical transition between a site and the abutting roadway. Driveways should be located and designed to minimize impacts on traffic while providing safe entry and exit from the development served. The location and design of the connection must take into account characteristics of the roadway, the site, and the potential users.

The actual width and length of driveways shall be subject to internal and external traffic flow considerations. The driveway width considerations include, but are not limited to the number of lanes, the driveway geometrics, internal obstructions, traffic safety, etc. The length of driveways shall be designed to provide for an uninterrupted traffic flow on the public street. This will require that the entering vehicles not be confronted with maneuvering vehicles at the immediate point of entry, thus requiring other entering vehicle(s) to stop in the through traffic flow. The driveway length therefore, will be subject to the anticipated required stacking length of entering and exiting vehicle during the peak period.

1.

For driveways that will be signalized, driveway length should be determined by a traffic study of expected traffic and queues. An important measurement in determining the driveway length is the outbound queue.

2.

For unsignalized driveways, the following minimum lengths will be used:

Land Use	Driveway Length (In Feet)
Any major entrance with 4 or more total lanes in the in the driveway. Typically malls, and "Super" retail centers	300 or greater, based on traffic study
Regional Shopping Centers (over 150,000 sq. ft.)	250
Community Shopping Center (100-150,000 sq. ft.) (Supermarket, drug store, etc.)	150
Small Strip Shopping Center	50
Smaller Commercial Development (convenience store with gas pumps)	30

 

3.

For residential developments, the maximum length shall be:

Land Use	Driveway Length (In Feet)
Residential Developments	250

 

B.

Driveway Grades

1.

Driveway grades shall conform to the requirements of FDOT Roadway and Traffic Design Standard Indices, latest edition.

2.

For driveways with high volumes and where curve radii turnouts would be a prime benefit to traffic movements, the following factors should be considered:

a.

It is desirable to have driveway slope upward from gutter line without any vertical curve. The upward slope with curbs will allow better control of drainage.

b.

It is desirable to have a relatively flat area adjacent to the roadway, where vehicles may turn off without an immediate climbing or descending need. Then exiting vehicles may wait to enter traffic flow at approximately roadway level.

c.

Within the limits of curve radii, no drop curb shall be allowed except as required for curb cut ramps.

C.

Traffic Control Devices

1.

The installation of signs and pavement markings at private roadways and residential or commercial driveways, and the installation of traffic signals at high-volume commercial Type III driveways may be required in order to provide for safe and efficient movement of traffic. All traffic control devices shall be installed in accordance with the Manual on Uniform Traffic Control Devices (MUTCD) and the current County standards and specifications and shall be approved by the County Public Works Department, Traffic Section.

2.

The approval to install traffic signals shall be based on a traffic engineering study which addresses the warrants, the design, and the operation of the signals. The study and design shall be approved by the County Public Works Department, Traffic Section and FDOT, if on the State Highway System. The responsibility for the engineering study shall rest with the permittee. If a traffic signal is installed, all signal elements and appropriate portions of the access approach to assure efficient signal operation, shall be on public right-of-way or on easements granted to the public.

3.

Any required traffic control devices, including signs, signals or pavement markings shall be installed by the permittee. The permittee shall be responsible for all purchase and installation costs involved.

D.

Auxiliary Lanes

Auxiliary Lanes refer to left-turn, right-turn, acceleration, deceleration, and storage lanes. Developments which generate AM or PM Peak Hour Traffic which exceeds the following thresholds shall provide the following site related acceleration, deceleration, and storage lanes:

1.

If more than 20 left turning vehicles per hour on a two-lane arterial or collector roadway, then left turn lanes are warranted,

2.

If more than 50 right turning vehicles per hour on a two-lane arterial or collector roadway, then right turn lanes are warranted,

3.

If more than 40 right turning vehicles per hour, on a four-lane rural roadway, then a right turn lane is warranted,

4.

If more than 80 right turning vehicles per hour, on a four-lane urban roadway, then a right turn lane is warranted,

5.

If more than 60 right turning vehicles per hour, on a six-lane rural roadway, then a right turn lane is warranted,

6.

If more than 100 right turning vehicles per hour, on a six-lane urban roadway, then a right turn lane is warranted,

7.

On multi-lane roadways, left turn lanes shall be constructed when there are more than 20 left turning vehicles.

(Ord. No. 00-38, § 2, 11-2-00; Ord. No. 05-22, § 2, 11-17-05; Ord. No. 07-18, § 2, 7-19-07, eff. 10-1-07)