- Public Works
- Traffic Calming Program (Formerly Speed Humps)
Traffic Calming Program (Formerly Speed Hump Petition)
The City of Titusville Public Works Department regularly gets citizen requests for review of local traffic conditions with regard to volume and speed. Traffic calming is a method used to address both concerns while still maintaining access to City services.
What is Traffic Calming?
The primary purpose of traffic calming is to support the livability and vitality of residential and commercial areas through improvements in non-motorist safety, mobility, and comfort. These objectives are typically achieved by reducing vehicle speeds or volumes on a single street or a street network. Traffic calming measures consist of horizontal, vertical, lane narrowing, roadside, and other features that use self-enforcing physical or psycho-perception means to produce desired effects.
A variety of definitions are commonly used in the traffic calming field and although the exact wording may differ, the essence remains; traffic calming reduces automobile speeds or volumes, mainly through the use of physical measures, to improve the quality of life in both residential and commercial areas and increase the safety and comfort of walking and bicycling.
What is the Purpose of Traffic Calming?
Traffic calming has helped to increase the quality of life in urban, suburban, and rural areas by reducing automobile speeds and traffic volumes on neighborhood streets. The implementation of traffic calming on residential streets is illustrative of the tools that traffic engineers and planners can use to meet broader societal needs to facilitate all street users’ safe and efficient movement. Traffic calming measures can help to transform streets and aid in creating a sense of place for communities.
The practice of traffic calming has evolved in recent years from a neighborhood-specific treatment to an integral part of complete streets and other bicyclist/pedestrian-related projects. Although mostly known as a neighborhood-specific initiative, traffic calming can be implemented on different street types and in different areas, including commercial settings and rural areas. Neighborhood traffic calming as a stand-alone approach to address traffic concerns isn't as prevalent as in past decades, with fewer new or updated neighborhood traffic calming programs due to funding constraints. However, the desire of citizens to slow automobile speeds or reduce volumes on streets adjacent to their homes has not decreased, and neighborhood traffic calming programs often provide the most effective way for residents to request traffic calming on residential streets.
Traffic calming within neighborhoods is unique as local residents are often the primary group interested in addressing automobile speeds and traffic volumes. Therefore, it is important that there continue to be a clear process for the planning, evaluation, and implementation of neighborhood traffic calming. As a comparison, the other major uses of traffic calming in cities are driven by multiple facets, whether by the bicyclist advocacy community in the case of bicycle boulevards or by safety advocates in the case of complete streets projects and emerging Vision Zero policies, for example. Neighborhood traffic calming continues to provide residents with a means to address traffic concerns in their neighborhoods.
The importance of reducing vehicle speeds cannot be overstated in an area where there is potential for conflict between a pedestrian and a motor vehicle. The slower the speed of the motor vehicle, the greater the chances are for survival for the pedestrian. If struck by a motor vehicle traveling at a speed of 20 miles per hour or less, a pedestrian is typically not permanently injured. Pedestrians are usually fatally injured if struck by a motor vehicle traveling at a speed of 36 miles per hour or more.
City of Titusville Traffic Calming Process Map
STEP 1 - Identification of Traffic Concern and Eligibility Review
Identification and eligibility determination of neighborhood traffic concerns consist of the following five-step process:
- Resident completes Request Form and submits to Public Works Department;
- Public Works Department collects basic speed and volume data;
- Public Works Department determines if the concern is eligible for traffic calming process;
- If eligible, Public Works Department determines “Affected Areas” and “Impacted Areas”;
- Residents obtain signatures from at least 50% plus 1 of the property owners within "Impacted Area” and submit them to Public Works Department.
A. Resident Completes Request Form and Submits to Public Works Department
The process starts when a resident or community group submits a Request Form, which can be found on the City website, to the Public Works Department. A copy of the Request Form and accompanying Traffic Study petition form is included in the Appendix. City staff will determine if the street or intersection of concern is applicable for consideration by the Traffic Calming Program. To be eligible for the program, the street must:
- Be a residential neighborhood under the City of Titusville’s jurisdiction;
- Have traffic volumes greater than 300 vehicles per day;
- Have a posted speed limit of 30 mph or less;
- Be at least 500 feet in length;
- Not be cul-de-saced.
B. Public Works Department collects basic speed and volume data
Once the Request Form has been reviewed by staff, the next step in the Traffic Calming Program involves collecting related traffic data to confirm the existence and magnitude of the traffic concern. Public Works Department will obtain site data including traffic volumes and speeds.
C. Public Works Department determines eligibility for traffic calming process
After the Public Works Department determines project eligibility, if there are numerous eligible projects in the queue, then the Public Works Department will prioritize the project areas. Prioritizing factors include:
- First come, first served;
- The need for traffic calming in the requested area. Based on the data collected, priority in the program may be determined by definable criteria related to:
- Traffic Speeds:
As motor vehicle speed increases, noise increases, and pedestrian and bicycle safety decreases. Some of the most dangerous traffic safety situations involve infrequent vehicles traveling substantially above the speed limit.
- Daily Traffic Volume Levels:
As motor vehicle volume increases, noise increases, and pedestrian and bicycle access decreases. This also causes the local function and feel of a street to diminish. From studies measuring resident opinions, the ideal traffic volume on a local neighborhood street is less than 300 vehicles per day (vpd), and residents generally are able to accept volumes up to 800 vpd.
- Traffic Speeds:
Table 1: Traffic Calming Thresholds
The table below summarizes the traffic concern characteristic thresholds required for a neighborhood street to be considered for traffic calming considerations. One or more of the three thresholds should be met to proceed with traffic calming measures.
|Traffic Criteria||Minimum Threshold|
|85th Percentile Speed||Greater than 5 mph over the posted speed limit|
|Significant Speeding||10% of traffic at or greater than 10 mph over the posted speed|
|Daily Traffic Volume||Exceeds 800 vpd on neighborhood streets or 1,500 vpd residential collectors|
If the results of the study conclude that the criteria for traffic calming have not been met, staff will conclude that the concern is not eligible for the traffic calming program at this time. The concern cannot be brought back to the City for three years unless something significantly changes existing conditions.
If the review of the data verifies that one or more of the thresholds have been met, they will determine the “Affected Areas” and “Impacted Areas” as described below.
D. Public Works Department Determines “Affected Areas” and “Impacted Areas”
After the City receives a traffic concern and determines it is eligible for the Traffic Calming Program, staff will define an “Affected Area” and an “Impacted Area.” An “Affected Area” includes all property directly affected by the traffic issue. An “Impacted Area” includes any property that would be impacted by any proposed traffic management solution.
The size and extent of the impacted area will take into consideration the type of traffic calming being proposed, the type of properties in the vicinity, and the characteristics of the street network surrounding the proposed project site(s).
These areas may include:
- All properties abutting the proposed street segment to be modified.
- All properties on adjacent street(s) with ingress/egress only possible via the modified street segment.
- All properties on adjacent street(s) that have alternative points of ingress/egress but will be otherwise affected by the modified street segment.
Spot-specific concerns will generally relate to a particular intersection or street segment, whereas neighborhood-wide concerns will generally relate to conditions or behaviors affecting the neighborhood street network. The City may elect to treat some spot-specific concerns as neighborhood-wide concerns if it decides that they could be better addressed in the context of the street network system. At the City’s discretion, the potentially affected area for a spot-specific concern may be extended to the entire street block. The potentially affected area for a neighborhood-wide concern should generally be a distinct area that is bounded or bisected by major roadways or geographic features. If the traffic concern influence area (but not the specific street being considered) may impact a larger neighborhood area the City will inform residents of the larger neighborhood area of the perceived problem and potential traffic calming alternatives under consideration.
E. Residents obtain signatures from at least 50% plus 1 of property owners within "Impacted Area” and submit to Engineering.
The City will provide a map or description of the impacted area indicating individual properties in the area to the requester. Requesters must obtain signatures from at least 50% plus 1 of the property owners within the impacted area to move forward with the request for a neighborhood traffic management effort (the petition can be found in Appendix).
Step 2 - Initial Traffic Calming Phase One Solutions
Generally, it is desirable to address traffic problems with the least restrictive measures possible and move to more costly geometric solutions only after other measures have proven ineffective. Therefore, City staff may choose to implement fairly low-cost, undisruptive initial traffic management solutions before proceeding into more formative calming measures. These solutions fall into three categories: Encouragement, Enforcement, and Engineering. The categories are explained below.
The neighborhood can be educated concerning the traffic management problem. This education can include the use of a Radar speed trailer.
If police resources are available, regular and random patrol and enforcement activities can address speeding and other traffic control concerns.
The City may choose to install enhanced signing or pavement markings to address concerns. Initial cost and any ongoing maintenance costs of these Phase One measures may need to be paid for by the residents. Examples of these measures can include:
- Roadway narrowing through pavement marking of medians or bike lanes
- Increased visibility of pedestrian crossing pavement markings
- Additional pedestrian crossing signs
- Appropriate speed limit signs
Step 3 - Phase Two Solutions
After a predetermined time period, the Public Works Department will evaluate the effectiveness of the non-construction elements of the Phase One plan. The results of this study will be presented to the petitioner. If the Phase One efforts are not satisfactory, Phase Two traffic calming techniques will be considered.
The Public Works Department will consider Phase Two engineering solutions such as bump outs, chokers, traffic circles, chicanes, speed tables, diverters, closings, etc. The City will analyze the options and make a recommendation for the appropriate engineering countermeasures. The Public Works Department will take into consideration such items as street sweeping, and the impact to ambulances, fire, and police when determining these solutions. Solutions in the Traffic Calming Toolkit are discussed in the Appendix.
Residents in the affected area must achieve a 50% + 1 positive vote of the property owners in the affected area. There is one vote per property. The Public Works Department will finalize construction plans and project specifications upon approval of the necessary funds to complete the project.
Step 4 – Priority Ranking Process
Because of limited resources, the City may not be able to implement all traffic calming projects proposed by the Traffic Calming Program. The Traffic Calming Program scoring system allows the City to prioritize traffic calming projects based on the following neighborhood street and land use characteristics. These characteristics include the initial set of traffic calming guideline thresholds plus additional land use and City planning-related considerations such as:
- Traffic speeds
- Daily traffic volumes levels
- Motor vehicle crashes
- Proximity to schools and parks
- Critical locations
- Pending road construction
- Relationship to neighborhood and City plans
B. 85th Percentile Motor Vehicle Speed
The point value for this criterion is equal to the 85th percentile motor vehicle speed (in miles per hour) measured on the subject street, minus 25.
C. Significant Motor Vehicle Speed
The point value for this criterion is the percentage of traffic that is traveling at least 10 mph above the speed limit.
D. Average Daily Traffic Vehicle Volume
The point value for this criterion is equal to the average daily traffic vehicle volume (in vpd) divided by 1,000 and rounded to the nearest whole number. If possible, the motor vehicle volume should be measured over a 48-hour period.
E. Crash History
The point value for this criterion is the number of crashes that have occurred at this location over the last three years excluding non-correctable crashes such as those involving driver health-related seizures, or motorists operating a vehicle under the influence
F. Distance from Park or School
Motor vehicle noise can have an adverse impact on parks and schools. In addition, these facilities typically attract pedestrians and bicyclists, especially children. Bicycle and pedestrian volumes (or demand) are typically the highest on streets adjacent to these facilities and decrease as the distance from the facility increases.
The point value for this criterion is equal to one one-hundredth of the difference of 1,000 and the linear street or sidewalk walking distance between the subject street and the nearest park or school. The minimum point value is 0. Other pedestrian-oriented facilities (such as the library or pool) may also be considered for this criterion. For example, if the problem area on the subject street is 400 feet away from a park, the point value associated with this distance will be (1,000- 400) x 0.01 = 6.
G. Critical Location
Certain intersections or street segments have the potential for acute conflict between motorized and non-motorized traffic. These “critical locations” may include:
- Multiuse trail crossings
- Intersections where the minor street is marked as a bicycle route
- Intersections staffed by a school crossing guard
- Streets or intersections with high bicycle or pedestrian volumes
- Streets or intersections with high (unmet) bicycle or pedestrian demand
- Streets or intersections within a school zone
A project that improves conditions for bicyclists or pedestrians at a critical location may receive up to 10 points for this criterion, depending on the extent of both the need and the improvement.
H. Pending Road Construction
Traffic calming measures can be easily implemented at little additional cost when roadway plans are prepared for reconstruction. When residential streets are planned for reconstruction, the City may seek to capitalize on this opportunity and encourage the implementation of traffic calming measures as part of the reconstruction project. To acknowledge this criteria and opportunity, up to 10 points are awarded to the scoring.
I. Neighborhood and City Planning
Neighborhood-wide projects typically require extra effort and produce more comprehensive traffic management solutions. To acknowledge this effort, the City may award 5 points to a neighborhood-wide project for this criterion. This is a subjective measure.
The score for a neighborhood-wide project is the average of scores for individual project elements rounded up to the next whole number. The addition of 5 points reduces the penalty incurred by individual project elements that score lower than the overall project average but as a Scoring Priority Calculation system provide a positive synergistic enhancement to calming the neighborhood street network problem.
J. Formal Review
The table below summarizes the scoring criteria, which are explained in the following subsections. The proposed project’s score is the sum of the point values for each of the criteria. Projects with a score of 15.0 or more are eligible for physical traffic calming measures.
Table 2: Project Prioritization Scoring Criteria
|85th Percentile vehicle speed||85th Percentile motor vehicle speed (in mph) - 25|
|Excessive motor vehicle speed||Percent of traffic traveling at least 10 mph over the speed limit|
|Motor vehicle volume||Average daily motor vehicle volume (in vpd) / 1000|
|Distance from school or park||(1,000 - linear distance to nearest school or park in ft)/100|
|Critical location||Up to 10 points|
|Crash history||Number of crashes in last 3 years|
|Pending road construction||Up to 10 points|
|Neighborhood planning||5 points|
This score is used to prioritize the projects under implementation consideration. The project is placed on the Traffic Calming Project list, and its score is compared to other projects that have been proposed but not yet implemented. If the project receives a high score that places it near the top of proposed projects, the process continues.
Unimplemented projects remain on the Traffic Calming Project list for three years. Every three years, the advocate is notified and may submit a new application to keep the project on the list for an additional three years.
The Public Works Department will review the project and makes a recommendation to the City Council. This review includes the project score, the project action plan, the proposed measures, the results of any temporary installations (if applicable), and the results of the balloting.
The City Council will make the final determination on whether or not to implement the project.
Priority Scoring Example:
|85th Percentile is 33 mph||8 pts|
|20% > 10 mph||1.6 pts|
|ADT = 1200 vpd||1.2 pts|
|Nearest Park 400 ft||6 pts|
|No planned road const.||0 pts|
Projects with a score of 15.0 or more are eligible for physical traffic calming measures.
Acceptable Traffic Calming Measures
All traffic calming measures shall comply with the Manual of Uniform Minimum Standards for Design, Construction and Maintenance for Streets and Highways latest edition. The following measures are acceptable for Local Streets:
|Traffic Calming Measure||Segment or Intersection||Typical Cost|
|Lateral Shift||Segment||$6,000 - $15,000|
|Chicane||Segment||$8,000 - $10,000|
|Realigned Intersection||Intersection||$6,000 - $15,000|
|Traffic Circle||Intersection||$10,000 - $25,000|
|Small Modern & Mini-Roundabout||Intersection||$15,000 - $60,000|
|Speed Hump||Segment||$1,000 - $8,000|
|Speed Cushion||Segment||$2,500 - $6,000|
|Speed Table||Segment||$2,500 - $8,000|
|Offset Speed Table||Segment||$6,000 - $15,000|
|Raised Crosswalk||Both||$4,000 - $8,000|
|Raised Intersection||Intersection||$15,000 - $60,000|
|Street Width Reduction|
|Corner Extension||Intersection||$8,000 - $12,000|
|Choker||Segment||$10,000 - $25,000|
|Median Island||Both||$15,000 - $55,000|
|On-Street Parking||Segment||$1,000 - $6,000|
|Half Closure||Intersection||$3,000 - $40,000|
|Median Barrier||Intersection||$1,500 - $20,000|
|Forced Turn Island||Intersection||$1,500 - $20,000|
A lateral shift is a realignment of an otherwise straight street that causes travel lanes to shift in one direction. The primary purpose of a lateral shift is to reduce motor vehicle speed along the street. A typical lateral shift separates opposing traffic through the shift with the aid of a median island. Without the island, a motorist could cross the centerline in order to drive the straightest path possible, thereby reducing the speed reduction effectiveness of the lateral shift. In addition, a median island reduces the likelihood a motorist will veer into the path of opposing traffic, further improving the safety of the roadway for motorists.
A chicane is a series of alternating curves or lane shifts that are located in a position to force a motorist to steer back and forth out of a straight travel path. The curvilinear path is intended to reduce the speed at which a motorist is comfortable traveling through the feature. The lower speed could in turn result in a traffic volume reduction.
For the purpose of traffic calming, a realigned intersection is the reconfiguration of an intersection with perpendicular angles to have skewed approaches or travel paths through the intersection. The expectation is that these physical features will remove or discourage fast vehicle movements through the intersection.
The most common application is the conversion of a T-intersection with straight approaches into curving streets meeting at right angles. The result is the removal of all straight paths through the intersection.
A traffic circle is a raised island, placed within an unsignalized intersection, around which traffic circulates. A traffic circle forces motorists to use a reduced speed when entering and passing through an intersection, whether the vehicle path is straight-through or involves a turn onto an intersecting street.
A traffic circle can have Stop signs or Yield signs on the intersection approaches.
The primary benefit of a traffic circle is an expected reduction in the number of angle and turning collisions. An additional benefit is that it can slow high-speed traffic at the intersection.
A typical traffic circle has a horizontal clearance that is too small for a left-turning truck, emergency vehicle, or bus to circulate counterclockwise even with a partially mountable center island. If the local jurisdiction permits the movement, the large vehicle can make a left turn in front of the island. However, some jurisdictions prohibit turning in front of the island. A traffic circle is usually circular in shape but may be oval to fit a particular intersection.
Small Modern & Mini-Roundabout
A small modern roundabout and mini-roundabout is a raised island, placed within an unsignalized intersection, around which traffic circulates. The center island forces a motorist to use reduced speed when entering and passing through an intersection, whether the vehicle path is straight-through or involves a turn onto an intersecting street. It is also expected to reduce the number of angle and turning collisions.
Both a small modern roundabout and a mini-roundabout are designed in accordance with roundabout design principles. Both are designed so that all traffic can circulate counterclockwise around or partially over the center island.
The principal difference between a small modern roundabout and a mini-roundabout is found at the center island. For a small modern roundabout, the center island is not traversable and can be landscaped with ground cover, flowers, and street trees. In contrast, the center island of a mini-roundabout is fully traversable.
A speed hump is an elongated mound in the roadway pavement surface extending across the travel way at a right angle to the traffic flow. A speed hump is typically 3 inches in height (with applications as high as 4 inches) and 12 feet in length along the vehicle travel path axis (note: a speed hump that is 20 feet in length and flat in the middle is considered a speed table in this).
At typical travel speeds along a residential street or in a small commercial business district, a speed hump produces sufficient discomfort to a motorist driving above the speed hump design speed to discourage speeding. It encourages the motorist to travel at a slow speed both upstream and downstream as well as over the speed hump.