§ 78-140. Transportation system design.

(a)

Purpose and intent. This section establishes minimum requirements applicable to the transportation system, including public and private streets, bikeways, sidewalks, pedestrian ways, parking and loading areas, and access control to and from public streets. The standards in this section are intended to minimize the traffic impacts of development, and to assure that all developments adequately and safely provide for the storage and movement of vehicles consistent with good engineering and development design practices.

(b)

Compliance with county standards. All required elements of the transportation system shall be provided in compliance with the engineering design and construction standards contained in the Public Works Manual of Miami-Dade County, latest issue, and related standards.

(c)

Street classification system.

(1)

Generally.

a.

All streets (public and private) in the city are classified and mapped according to function served in order to allow for regulation of access, road and right-of-way widths, circulation patterns, design speed, and construction standard.

b.

Streets that are to be dedicated to the city are classified in a street hierarchy system with design tailored to function. The street hierarchy system shall be defined by road function and average daily traffic (ADT), calculated by trip generation rates prepared by the Institute of Transportation Engineers. Trip generation rates from other sources may be used if the developer demonstrates the alternative source better reflects local conditions.

c.

When a street continues an existing street that previously terminated outside the subdivision, or is a street that will be continued beyond the subdivision or development at some future time, the classification of the street will be based upon the street in its entirety, both within and outside of the subdivision or development.

d.

All development proposals containing new streets or taking access from existing streets shall conform to the standards and criteria contained in this section.

(2)

Arterial roads. This category of street is subdivided into principal arterial road and minor arterial road. Arterial roads provide links between communities or to limited access expressways. Arterial roads limit direct access from abutting properties except for regionally significant uses. No parking is allowed on any arterials. Each subcategory of roads shall conform to the usage, design and construction standards of the county.

a.

Principal arterial. These roads include the Palmetto expressway and U.S. Highway 27. Principal arterials provide regional and areawide accessibility at high speeds. These controlled access facilities shall be under the jurisdiction of a state or county agency. Principal arterials shall have a design speed of 45 miles per hour. The minimum acceptable peak hour level of service standard shall be LOS "D."

b.

Minor arterial. These roads link community districts to regional or state highways. Minor arterials may also give direct access to regionally significant land uses. These roads may take access from other arterials or freeways and may give access to any lower order nonresidential street type. Lots of less than 150 feet in width may not take access from a minor arterial. Minor arterials shall have a design speed of 45 miles per hour. The minimum level of service standard shall be LOS "D."

(3)

Collector roads. Collector roads provide access to residential or nonresidential uses and connect lower order streets to arterial streets. Design speeds and average daily traffic volumes will be higher than for lower order streets.

a.

Major collector. These streets serve as major community or commercial facilities and may carry through traffic. Major collector streets may take access from other major collectors and arterials, and may give access to any same or lower order street type. Lots of less than 50 feet in width may not take access from a major collector. Major collectors shall have a design speed of 35 miles per hour. Major collectors shall have a minimum ADT of 7,000. The minimum level of service standard shall be LOS "D." No parking is allowed on major collectors.

b.

Residential collector. Where possible, this order of street should be a half-section road. It may provide access for abutting land uses although the number of curb cuts shall be controlled by approved site plan design. Lots of less than 40 feet in width may not take access from a residential collector. This order shall have a maximum ADT of 2,000 and a design speed of 30 miles per hour.

(4)

Local streets. Local streets provide direct access to residential development, but may give access to nonresidential uses, provided average daily traffic (ADT) volume generated by the nonresidential use does not exceed applicable standards for the affected streets. All local streets should be designed to minimize unnecessary and/or speeding traffic. Each local street shall be classified and designed for its entire length to meet the following minimum standards:

a.

A local street is a frontage street which provides direct access to abutting properties and is designed to carry no more traffic than is generated on the street itself.

b.

The design speed for local streets is 15 to 25 miles per hour.

c.

Local streets in the north and central districts shall have a maximum ADT of 500.

d.

Local north-south streets in the north district shall not carry through traffic from NW 137th Street to Frontage Road.

e.

A cul-de-sac shall serve a maximum of 25 dwelling units and a have maximum ADT of 250.

f.

When a ten-foot moving lane is provided, two eight-foot parking lanes shall be provided, except that in apartment house areas, two moving lanes should be provided.

(d)

Rights-of-way.

(1)

Right-of-way widths. Right-of-way requirements for road construction shall be as specified in the Public Works Manual of Miami-Dade County. The right-of-way shall be measured from lot line to lot line.

(2)

Right-of-way requirements. Right-of-way locations for collector and arterial roads are identified in the transportation circulation map of the city, on file in the zoning department. Where roadway construction, improvement, or reconstruction is not required to serve the needs of the proposed development project, future rights-of-way shall nevertheless be reserved for future use.

(3)

Protection and use of right-of-way.

a.

No encroachment shall be permitted into existing rights-of-way, except for temporary use authorized by the city.

b.

Use of the right-of-way for public or private utilities, including but not limited to sanitary sewer, potable water, telephone wires, cable television wires, gas lines, or electricity transmission, shall be allowed subject to placement specifications in city or other applicable regulations.

c.

Sidewalks and bicycle ways shall be located within the right-of-way.

(4)

Vacation of rights-of-way. Applications to vacate a right-of-way shall not be approved unless the city council finds that all of the following requirements are met:

a.

The requested vacation is consistent with the transportation circulation map of the city.

b.

The right-of-way does not provide the sole access to any property.

c.

The requested vacation would not jeopardize the current or future location of any utility.

d.

The requested vacation is not detrimental to the public interest, and provides a positive benefit to the city.

(e)

Street design standards.

(1)

General design standards.

a.

All streets in a new development shall be designed and constructed pursuant to the standards in chapter 28, pertaining to subdivisions, Code of Miami-Dade County. Streets shall be dedicated to the city upon completion, inspection, and acceptance by the city.

b.

Private streets may be allowed within developments that will remain under common ownership, provided they are designed and constructed pursuant to the standards in chapter 28, pertaining to subdivisions, Code of Miami-Dade County.

c.

Streets in proposed subdivisions shall be connected to rights-of-way in adjacent areas to allow proper inter-neighborhood traffic flow by means of a collector street. If adjacent lands are unplatted, stub-outs in the new development shall be provided for future connection to the adjacent unplatted land.

d.

Local streets shall be arranged to discourage through traffic.

e.

The crown of all roads shall be six feet, six inches above sea level.

f.

Streets shall intersect as nearly as possible at right angles and in no case shall be less than 75 degrees.

g.

New intersections along one side of an existing street shall, where possible, coincide with existing intersections. Where an offset (jog) is necessary at an intersection, the distance between centerlines of the intersecting streets shall be no less than 150 feet.

h.

No two streets may intersect with any other street on the same side at a distance of less than 400 feet measured from centerline to centerline of the intersecting street. When the intersected street is an arterial, the distance between intersecting streets shall be no less than 1,000 feet.

(2)

Curbing requirement.

a.

Except in the R-TH and R-M1 zoning districts where valley gutters may be used, curbing shall be required for the purposes of drainage, safety, and delineation and protection of pavement edge along streets in the following cases:

1.

Along designated parking lanes.

2.

Where the surface drainage plan requires curbing to channel stormwater.

3.

Where narrow lots averaging less than 40 feet in width take direct access from a street upon which no on-street parking is allowed.

b.

All curbing shall conform to the construction standards in Chapter 28, pertaining to subdivisions, Code of Miami-Dade County.

(3)

Shoulders. Shoulders, where required, shall measure at least five feet in width and shall be required on each side of street and located within the right-of-way. Shoulders shall consist of stabilized turf or other material permitted by Chapter 28, pertaining to subdivisions, Code of Miami-Dade County. Shoulders and/or drainage swales are required as follows:

a.

According to city public works department requirements on local and residential collector streets where necessary for stormwater management or road stabilization.

b.

Where required, all residential streets shall provide two five-foot-wide shoulders. Shoulders should be grass surfaced except in circumstances where grass cannot be expected to survive. In no case shall the shoulders be paved.

c.

Where shoulders are required by the Florida Department of Transportation.

d.

On collector streets where curbing is not required.

e.

On arterial streets where curbing is not required.

(4)

Cul-de-sacs and turnarounds. Dimensions and design of the cul-de-sac moving lane and the turning radius or T configuration shall conform to the Miami-Dade County Public Works Manual.

(5)

Stub streets.

a.

Local and collector stub streets may be permitted only within subsections of a phased development for which the proposed street in its entirety has received final site plan approval.

b.

Residential collector and higher order stub streets may be permitted or required by the city provided that the future expansion of the street is deemed desirable by the city or conforms to an adopted traffic circulation map.

c.

Temporary turnarounds shall be provided for all stub streets providing access to five or more lots or housing units. Where four or fewer lots or units are being served, a sign indicating a dead-end street shall be posted.

(6)

Clear visibility triangle. In order to provide a clear view of intersecting streets to the motorist, there shall be a triangular area of clear visibility formed by two intersecting streets or the intersection of a driveway and a street. The following standards shall be met:

a.

Nothing shall be erected, placed, parked, planted, or allowed to grow in such a manner as to materially impede vision between a height of two feet and ten feet above the grade, measured at the centerline of the intersection.

b.

The clear visibility triangle shall be formed by connecting a point on each street centerline, to be located at the distance from the intersection of the street centerlines indicated in subsection c. below of this section, and a third line connecting the two points.

c.

The minimum distance from the intersection of the street centerlines for the various road classifications shall be as follows:

Road classification	Distance from street centerline intersection
Driveway or local street	100 feet
Collector	160 feet
Arterial	200 feet

 

(7)

Signage and signalization. The developer shall deposit with the city sufficient funds to provide all necessary roadway signs as may be required by the city, based upon county or state signage standards. At least two street name signs shall be placed at each four-way street intersection, and one at each T intersection. Signs shall be installed near light standards and free of visual obstructions. The design of street name signs shall be consistent, in a style appropriate to the community, and of uniform size and color.

(8)

Street trees.

a.

Street trees shall be provided in accordance with the standards established in Article VII, Landscape Requirements.

b.

No development shall be approved without reserving an easement, at the time of final plat approval, authorizing the city to plant shade trees within five feet of the required right-of-way boundary. No street shall be accepted for dedication until the easement required by this subsection has been provided.

(9)

Blocks.

a.

Where a tract of land is bounded by streets forming a block, such block shall have sufficient width to provide for two tiers of lots of appropriate depths.

b.

The lengths, widths, and shapes of blocks shall be consistent with adjacent areas. In no case shall block lengths in residential areas exceed 1,200 feet nor be less than 400 feet in length.

(f)

Sidewalks and bikeways.

(1)

When required.

a.

Projects abutting collector or arterial facilities shall provide sidewalks adjacent to the collector or arterial roadway. Projects in neighborhood retail (B-1), business (B-2), high density residential (R-M2), medium density residential (R-TH and R-M1), moderate single-family residential (R-1Z and R-1P), PUD, MU or MU-E districts shall provide sidewalks. Location of sidewalks shall be consistent with planned roadway improvements.

b.

All residential projects adjacent to or in the immediate vicinity of an activity center comprised of office, service, school, or recreation activities shall provide pedestrian and bicycle access from the development to the activity center.

c.

Pedestrian ways or crosswalks, not less than ten feet wide with a sidewalk meeting the requirements of this chapter, may be required by the technical review committee to be placed in the center of blocks more than 800 feet long where deemed necessary to provide circulation or access to schools, playgrounds, shopping centers, transportation and other facilities.

(2)

Design and construction standards. Design and construction of sidewalks, bikeways, or other footpaths shall conform to the requirements of Chapter 28, pertaining to subdivisions, Code of Miami-Dade County unless required to conform to the city's urban design guidelines.

(Ord. of 9-25-06)