Traffic Engineering

Traffic Calming


The purpose of this Section is to provide policies and procedures for design and installation of traffic calming devices within unincorporated Seminole County. On October 27, 2020, the Board approved the use of traffic calming devices on County roadways to reduce vehicle speeds.  The Board approves the use of the following traffic calming devices on County roadways to control vehicle speeds:

  1. Speed Cushions
  2. Mid-Block Chokers
  3. Chicanes
  4. Median/Center Islands
  5. Roundabouts
  6. Traffic Circles
  7. Gateway/Entry Features

Traffic calming devices will be approved by the County based on the latest Traffic Calming Criteria (see below).  As identified in the criteria, the roadway must have a documented issue with speeding.


The following Traffic Calming Criteria must be met before traffic calming devices may be installed on a roadway:

(1)        Roadway must have a documented speeding issue, the observed 85th percentile speed is greater than 8 mph over posted speed limit.

(2)        The maximum roadway volume must not exceed 3,000 vehicles per day.

(3)        The maximum posted speed on the roadway must not exceed 30 mph.

(4)        65% of all property owners along the roadway where the traffic calming devices are being installed must vote to approve the installation.

(5)        Functional spacing of devices (primarily for speed cushions or humps) is based on the following guidelines:

  • 300 feet – 400 feet between devices;
  •  No installation on curves or turns;
  •  Minimum of 100 feet from intersections or curves or turns; and
  • Spacing subject to adjustment for driveways.

(6)        Roadway must have driveways that directly access the road.

(7)        Roadway must not be a principal arterial, minor arterial or major collector roadway. Roadway must be a local street or minor collector that is evaluated on a case-by-case basis.

(8) Traffic calming devices should not be placed on any roadway that is a primary or routine response route for emergency vehicles, including departure routes from a fire station.

(9) Traffic calming devices must not increase response times by more than one minute or the total travel time to the furthest protected structure along the response route to more than 5 minutes.

The above criteria applies to the following traffic calming devices:  speed cushions (in addition to Section C below), mid-block chokers, chicanes, median/center islands and certain other devices from the 2005 Traffic Calming Program manual, such as mid-block chokers, chicanes and median/center islands. Other devices in the manual, such as, roundabouts, traffic circles and gateway/entry features, may have different criteria to be determined by the County Traffic Engineer or County Engineer on a case by case basis if those devices were desired.

Nothing above limits the County Traffic Engineer’s or County Engineer’s ability to install any devices upon the County roadway system that in their sole opinion is justified for the maximum safety of the motorists or residents and does not impede Public Safety operations.


Speed cushions must be designed to reduce as much as possible the impact to emergency vehicle response times. The following design considerations are to be used and any cushions installed on County roadways shall be approved by the County Engineer or County Traffic Engineer. Cushions may be fabricated from pre-fabricated rubber pieces, similar to Traffic Logix Speed Cushions or equal, or in-place constructed asphalt sections. Cushions should be made up of two (2) or three (3) sections for each location along the roadway. The width of the section must be six feet (6’) and they must be installed with two foot (2’) gaps between sections. The length of the sections shall be twelve feet (12’) or longer to set the desired speed over the cushion. The general design of cushions will be subject to approval by the County Engineer or County Traffic Engineer. The City of Orlando’s Speed Cushion design, was used as a template.   


Communities seeking information on the possible creation of MSBUs for installation of traffic calming devices should refer to Section 22.10 of this Code.


Approval of 65% of the property owners along the roadway where traffic calming devices are located is necessary for the Board to consider removal of any traffic calming devices. 


Resolution 2020-R-118 adopted October 27, 2020

Resolution 2024-R-55 adopted March 5, 2024


The Board recognizes there is no dedicated funding for any traffic calming devices at this time.  The Board may decide to dedicate funding in the future through a budgeted program or through individual projects.  In the absence of County funding or assistance, communities may receive County approval to design and install traffic calming devices through the County’s Municipal Service Benefit Unit (MSBU) program.

What is an MSBU? An “MSBU” (Municipal Service Benefit Unit) is a non-ad valorem assessment district created to fund a public service or capital improvement. An MSBU consists of a group of properties that share in the benefit and cost of the service provided. The assessment allocated to each property is based on the service cost, total number of benefit units and the number of benefit units assigned to each property. A benefit unit may be a parcel, dwelling, linear foot or other equitable unit.  In short, you and your affected neighbors will pay an amount annually for a determined number of years to fund the traffic calming measures desired for your roadway.  More information on the MSBU program

The cost for speed cushions varies depending on the material.  Pre-fab rubber cushions that were used at the County’s four (4) pilot project locations were $6,200 per location.  This was for a set of two (2) that were good for a roadway width of 24’ or less.  Assuming 300’-400’ spacing between locations, rubber cushions are roughly $93,000 per mile.  Asphalt cushions are significantly less expensive at about $4,000 per location or $60,000 per mile.  The other traffic calming device options, #2 through #7 above, are significantly more expensive, current estimated costs.     



The following process applies to the County’s evaluation of speeding complaints and Traffic Calming Devices for a particular roadway:

  1. When a speeding complaint is received, Traffic Engineering will field verify that adequate speed limit signage is in place for enforcement and make changes if necessary.
  2. Traffic Engineering will then schedule a speed and volume study. The results of this study will be shared with the residents and the Sheriff’s Office.
  3. If the speed study indicates there is an issue with excessive speeds (85th-percentile speed is at least 5 mph over posted speed limit), Traffic Engineering will first consider non-restrictive measures, such as: education, neighborhood meetings, selective law enforcement, additional signing or striping, temporary or permanent speed radar feedback signs, connected vehicle basic safety messages, or other Intelligent Transportation Standards Technologies.
  4. After a minimum of 60 days, another speed study will be conducted.
  5. If this new speed study indicates there is still an issue with excessive speeds (85th percentile speed is at least 5 mph over posted speed limit), Traffic Engineering may consider additional non-restrictive measures, evaluate their effectiveness for a minimum of 60 days and conduct another speed study.
  6. If all non-restrictive measures have been exhausted and a speed study still indicates excessive speeds (85th-percentile speed is at least 8 mph over posted speed limit), then restrictive measures, such as the installation of Traffic Calming devices, will be considered if feasible.
  7. Traffic Engineering will first evaluate remotely, and field verify, if necessary, a solution and cost estimate.
  8. Traffic Engineering will forward recommendations to the Fire Department for review and evaluation.
  9. If the Fire Department does not deny the request based on their initial criteria (the route being a primary or routine route, the response time increased by more than 1 minute or the total travel time to the furthest protected structure along the response route is more than 5 minutes), they will determine the area beyond the initial roadway in question that may be impacted by increased response times.
  10. Letters presenting the Fire Department findings will be sent to households in the impacted area, along with a ballot asking for their vote on the Traffic Calming project.
  11. Approval by a simple majority (50% +1) of all returned ballots will be required to proceed. Results will be shared with the residents and Board.
  12. If approved and the applicant still wishes to proceed with the recommendations proposed by staff, the funding source will be determined by County staff.
  13. Each traffic calming project shall be approved by the Board, regardless of funding source. 

Seminole County Traffic Calming Request Form