HomeMy WebLinkAboutExhibit 7.1.0k1.1.1•9.414.1.1.1,1•1.1.1
CITY OF MIAMI
TRAFFIC CALMING STUDY
FINAL
Prepared by
Marlin Engineering, INC.
MAY25 2005
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2 191 NW 97 Avenue Miami, Florida 33172-2313 Tel. (305) 477-7575 Fax 305) 477-7590
www.marlinengineering.com
City of Miami
The Silver Bluff Traffic Calming Study
CITY OF MIAMI
THE SILVER BLUFF
TRAFFIC CALMING STUDY
Prepared by
Marlin Engineering, Inc.
FINAL
May 25, 2005
Marlin Engineering, Inc.
May 25, 2005
City o7 Miami
The Silver Bluff Traffic Calming Study (Final)
I
EXECUTIVE SUMMARY
This report presents the findings of a traffic calming study conducted by Marlin
Engineering, Inc. for the Silver Bluff area in the City of Miami, Miami -Dade County. This
study addresses area -wide traffic conditions and public concerns within local residential
streets, and provides a traffic calming plan for the study area. Marlin Engineering, Inc.
collected existing traffic information, including speed, volume, three-year (2001-2003
crashes, as well as, land use and transit data.
High number of traffic crashes, speeding and traffic intrusions were defined as
major factors that affected residents' safety and mobility within the study area.
To mitigate the existing problems, the Marlin Engineering Inc. analyzed existing traffic
conditions and identified critical intersections and roadway segments. A methodology to
warrant, select and prioritize traffic calming projects was developed. Feasible traffic
calming alternatives and appropriate measures are recommended for the warranted
intersections and/or roadway segments (see Section 4.2). Preliminary cost estimate for
the installation of the recommended traffic calming devices is about $ 470,000.
Marlin Engineering, Inc.
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The Silver Bluff Traffic Calming Study (Final)
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TABLE OF CONTENTS
1.0 INTRODUCTION 1
1.1 Purpose 1
1.2 Background 1
1.3 Objectives 1
2.0 EXISTING TRAFFIC CONDITIONS 3
2.1 Roadway Characteristics 3
2.2 Land Use 3
2.3 Public Transit 3
2,4 Traffic Control Devices 5
2.5 Roadway Characteristics Inventory 5
2.6 Pedestrian and Bicycle Facilities 7
2.7 Safety 7
3.0 NEIGHBORHOOD TRAFFIC MANAGEMENT 8
3.1 Public Involvement 8
3.1.1 First Workshop 8
3.1.2 Community Walk 8
3.2 Traffic Data Collection 9
3.3 Traffic Data Analysis Methodology 9
3.4 Traffic Calming Analysis 10
3.4.1 General Requirements, Constrains and Data Collection ,. 10
3.4.2 Selection Criteria 11
3.4.3 Scoring and Prioritization System 12
4.0 TRAFFIC CALMING ALTERNATIVES 14
4.1 Type of Traffic Calming Measures .14
4.2 Recommended Traffic Calming Locations 15
5.0 TRAFFIC CALMING GUIDELINES AND FUNDING STRATEGIES 23
5.1 Guidelines for Traffic Calming Projects 23
5.2 Funding Strategies 25
5,2.1 Local Funds 25
5.2.2 Non -Local Funds 27
5.2.3 Funding Policies 28
6.0 RECOMMENDATIONS 29
REFERENCES 30
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The Silver Bluff Traffic Calming Study (Final)
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LIST OF TABLES
Table 1 - Summary of Land Use Type within the Study Area 5
Table 2 - Street Functional Classification and Pavement Width 6
Table 3 - Selection Criteria Warrants 11
Table 4 - Scoring System for Prioritizing Warranted Traffic Calming Locations 13
Table 5 - Recommended Traffic Calming Devices by Locations 16
Table 6 - Examples of Local Funds Including Cost -Sharing Programs 26
Table 7 - Examples of Landscaping Maintenance Policies 27
Table 8 - Examples of Non -Local Funds 28
Table 9 - Cost Estimate of Recommended Traffic Calming Devices 29
LIST OF FIGURES
Figure 1 - Roadway System within Study Area 4
Figure 2 - Different Traffic Calming Measures Classified by Purpose 15
Figure 3 - Traffic Calming Plan for Silver Bluff Area 17
Figure 4 - Proposed Intersection Improvement at SW 28th Lane & SW 27th St 18
Figure 5 - Proposed Intersection Improvement at SW 26th Lane & SW 23rd Ave 18
Figure 6 - Proposed Access Management along SW 3rd Avenue 1 19
Figure 7 - Proposed Access Management along SW 3rd Avenue 2 20
Figure 8 - Proposed Access Management along SW 3rd Avenue 3 21
Figure 9 - Proposed Intersection Improvement at SW 16th Avenue and SW 3rd Avenue
22
Figure 10 - Recommended Traffic Calming Study Process 24
LIST OF APPENDIXES
APPENDIX A: Silver Bluff Area Existing Traffic -related Conditions
APPENDIX B: Silver Bluff Area Traffic Calming Study Public Involvement
APPENDIX C: Silver Bluff Area Traffic Calming Study Data Collection and
Selection Procedures
APPENDIX D: Policy for Traffic Flow Modification by City of Coral Gables
APPENDIX E: Typical Designs For Recommended Traffic Calming Devices
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City of Miami
The Silver Bluff Traffic Calming Study (Final)
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1.0 INTRODUCTION
1.1 Purpose
The purpose of this study is to analyze existing traffic conditions within the Silver Bluff
area in the City of Miami. The study area is bounded by SW 22hd Street from the north,
South Dixie Highway (US-1) from the south, SW 27th Avenue from the west, and SW 3rd
Avenue from the east. The study identifies the traffic related problems on residential
streets, and recommends appropriate traffic calming measures at warranted locations.
This study also defines guidelines, methodology and funding strategies for traffic
calming and mitigation projects.
1.2 Background
The City of Miami is a world famous city bursting with its international culture, tropical
attractions, water sports, night recreations, and shopping. The Silver Bluff area is a
typical residential community close to Downtown Miami area. New developments,
including high-rise residential buildings and mixed use residential and office buildings,
have been planned or under construction along SW 27th Avenue and SW 22nd Street
(Coral Way). Along the boundary of the neighborhood, the major land uses are
shopping centers, office buildings, multifamily, and condominiums. Within the
neighborhood there are approximately 1233 single families, 258 duplexes, and 110
commercial properties. The commercial land uses are the boundary of the study area.
The City of Miami is committed to providing continuous improved quality of life style and
to maintaining safe transportation throughout its roadway network. Some of the major
traffic problems along the City's local residential streets are the high traffic volume,
speeding and traffic intrusions. Many residents are requesting the installation of traffic
calming devices to reduce vehicle speeds, decrease traffic volumes, discourage cut -
through traffic, and minimize the impact of motorized traffic on residential
neighborhoods. Thus, the City adopted the Miami -Dade County Traffic Flow
Modification Guidelines, to develop a calming plan for the study area.
1.3 Objectives
This report focuses an addressing existing traffic conditions at critical locations,
identifying feasible improvement alternatives and recommending solutions for
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The Silver Bluff Traffic Calming Siudy (Final) 2
implementation through traffic calming projects. The following goals have been set to
accomplish these objectives:
• Consolidate existing traffic data
• Determine critical locations within the Silver Bluff area
• Organize workshop and community walk with the study area residents
Perform additional traffic data collection
Perform traffic calming analysis
Develop traffic calming alternatives
Prepare preliminary recommendations for the City review
Submit study results to Miami -Dade County
Present study results to City Commissioners
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The Silver Bluff Traffic Calming Study (Final)
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2.0 EXISTING TRAFFIC CONDITIONS
2.1 Roadway Characteristics
The Silver Bluff neighborhood is surrounded by state major and minor arterials. The
Silver Bluff roadway system is shown in Figure 1.
The study area is served by several major and minor urban arterials:
• SW 27th Avenue (major arterial) at the west
• SW 22"d Street/Coral Way (minor arterial) at the north
• South Dixie Highway/US-1 (major arterial) at the south
• SW 3rd Avenue (local road) at the east
• Minor arterial, SW 22nd Avenue and SW 17th Avenue cross through the study
area in the north -south direction.
2.2 Land Use
The land use within the study area is mainly single family residential (84%), with the
exception of the parcels along the major or minor arterials, where the land use is a mix
of commercial and offices. Table 1 presents the summary of land use type within the
Silver Bluff area. Appendix A, Figure Al depicts the land use of the study area.
2.3 Public Transit
The study area is served by the Miami -Dade Bus Transit Routes No. 12, 22, 24, and 27.
The Metrobuses are running on major or minor arterials. Metrorail runs along US-1. No
Metrorail stations directly serve the study area. The public transit services are depicted
in Appendix A, Figure A2.
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SW 22NDTEE _.
SW 23RD ST
SW 23RD TE
1.4
1 SW 24TH ST
2
SW 24TH TE
SW 25Tii STD
SW 25TH TE
SW�_. 23TH TE ---
sw 26TH ST
SW 267H TE
SW 26TH EA
SW 27TH ST
tN
w
SW 26TH ST
SW 22ND TE
5 23RD ST
SW 23RD TE
m
SW 24TH ST
it
SW 24TH 'iE
2'RD ST
}.
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SW 22ND TE
SW 23RD ST
Legends
Study Area Boundary
FOOT Ftuldass
Urban Principal Arterial
inn@= Urban h5nor Arterial
Gomm Urban collector
Urban Local
Local Residential Street
Figure 1 - Roadway System
within Study Area
City of Miami
The Silver Bluff Traffic Calming Study (Final)
5
Table 1 - Summary of Land Use Type within the Study Area
Land Use Type
No. of Parcels
Percentage
tty,Av,��y `�� „r
1,233
84.0%
Multi -Family (including
Townhouses and Duplexes)
258
12.5%
Shopping Center,
Commercials, Offices
110
2.9%
Other
38
0.6%
Total
1,639
100.00%
2.4 Traffic Control Devices
All intersections within the residential area are controlled by either two-way or four-way
stop signs, with the exception of several intersections along minor or major arterials
controlled by traffic signals. Within the residential areas, pavement markings and stop
bars are either faded or missing. The posted speed limit along local residential streets
is 30 mph. Appendix A, Figure A3 shows the existing traffic control devices within the
study area.
2.5 Roadway Characteristics Inventory
The pavement width of the Silver Bluff area street network varies from 17 feet to 34 feet.
Center line pavement markings and some of the stop bars are missing. Sight distance
problems exist within residential roadways, which are caused by landscaping and on -
street parking close to the intersection. Table 2 presents the functional classification
and the pavement width for the street network within the study area.
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The Silver Bluff Traffic Calming Study (Final)
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Table 2 - Street Functional Classification and Pavement Width
Street Name
Location
Street
Classification
Posted speed Limit
_MPH)
Width (feet)
SW 23RD AVE
SW 23 AVE S/0 SW 22 TERR
Local Residential
30
28
SW 23RD AVE
SW 23 AVE S10 SW 24 TERR
Local Residential
30
34
SW 22ND TERR
SW 22 TERR EI0 SW 25 AVE
Local Residential
30
34
SW 24TH AVE
SW 24 AVE SIO SW 22 TERR
Local Residential
30
34
SW 24TH AVE
SW 24 AVE S/0 SW 24 TERR
Local Residential
30
34
SW 25TH AVE
SW 25 AVE S/O SW 22TERR
Local Residential
30
28
SW 25TH AVE
SW 25 AVE S/O SW 24 TERR
Local Residential
30
28
SW 23RD AVE
SW 23 AVE S/O SW 26 ST
Local Residential
30
28
SW 25TH AVE
SW 25 AVE S/O SW 26 ST
Local Residential
30
24
SW 24TH AVE
SW 24 AVE S/0 SW 26 ST
Local Residential
30
34
SW 21 ST AVE
SW 21 AVE Nl0 SW 23 TERR
Local Residential
30
28
SW 21ST AVE
SW 21 AVE S/O SW 23 TERR
Local Residential
30
28
SW 24TH ST
SW 24 ST EI0 SW 21 AVE
Local Residential
30
28
SW 19TH AVE
SW 19 AVE NI0 SW 23 ST
Local Residential
30
28
SW 18TH AVE
SW 18 AVE S/0 SW 22 TERR
Local Residential
30
28
SW 18TH AVE
SW 18 AVE S/O SW 24 ST
Local Residential
30
28
SW 24TH ST
SW 24 ST E/0 SW 25 AVE
Local Residential
30
34
SW 23RD ST
SW 23 ST El0 SW 23 AVE
Local Residential
30
34
SW 23RD TERR
SW 23 TERR W/0 SW 23 AVE
Local Residential
30
34
SW 22ND TERR
SW 22 TERR E/0 SW 21 AVE
Local Residential
30
28
SW 22ND TERR
SW 22 TERR W/O SW 17 AVE
Local Residential
30
28
SW 23RD ST
SW 23 ST El0 SW 19 AVE
Local Residential
30
28
SW 23RD TERR
SW 23 TERR Ei0 SW 21 AVE
Local Residential
30
28
SW 23RD TERR
SW 23 TERR E/0 SW 18 AVE
Local Residential
30
28
SW 23RD ST
SW 23 ST E/O SW 22 AVE
Local Residential
30
28
SW 24TH TERR
SW 24 TERR E/O SW 25 AVE
Local Residential
30
34
SW 24TH TERR
SW 24 TERR W/O SW 22 AVE
Local Residential
30
34
SW 25TH ST
SW 25 ST W/O SW 23 AVE
Local Residential
30
34
SW 25TH ST
SW 25 ST E/O SW 25 AVE
Local Residential
30
34
SW 24TH TERR
SW 24 TERR W/O SW 18 AVE
Local Residential
30
28
SW 24TH TERR
SW 24 TERR E/0 SW 22 AVE
Local Residential
30
28
SW 24TH ST
SW 24 ST WI0 SW 23 AVE
Local Residential
30
34
SW 23RD ST
SW 23 ST MO SW 25 AVE
Local Residential
30
34
SW 22ND TERR
SW 22 TERR W/O SW 23 AVE
Local Residential
30
34
SW 25TH TERR
SW 25 TERR E/O SW 23 AVE
Local Residential
30
34
SW 25TH TERR
SW 25 TERR W/O SW 24 AVE
Local Residential
30
18
SW 26TH ST
SW 26 ST W/0 SW 23 AVE
Local Residential
30
28
SW 26TH LN
SW 26 LN E/O SW 25 AVE
Local Residential
30
29
SW 24TH ST
SW 24 ST W/O SW 18 AVE
Local Residential
30
28
SW 25TH TERR
SW 25 TERR W/O SW 21 AVE
Local Residential
30
21
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The Silver Bluff Traffic Calming Study (Final)
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Street Name
Location
Street
Classification
Posted speed Limit
(MPH)
Width (feet)
SW 25TH ST
SW 25 ST W10 SW 19 AVE
Local Residential
30
22
SW 28TH LN
SW 28 LN W/O SW 25 AVE
Local Residential
30
34
SW 27TH ST
SW 27 ST W/0 SW 23 AVE
Loca{ Residential
30
34
SW 27TH ST
SW 27 ST W/0 SW 25 AVE
Local Residential
30
34
SW 26TH LB
SW 26 LN El0 SW 24 AVE
Local Residential
30
29
SW 21ST AVE
SW 21 AVE S/0 25 ST
Local Residential
30
12
SW 23RD ST
SW 23 ST W/O SW 14 AVE
Local Residential
30
28
SW 23RD ST
SW 23 ST E1O SW 14 AVE
Local Residential
30
28
SW 22ND TE
SW 22 TERR W10 SW 14 AVE
Local Residential
30
28
SW 22ND TE
SW 22 TERR E/0 SW 14 AVE
Local Residential
30
28
SW 13TH AVE
SW 13 AVE N/0 SW 22 TER
Local Residential
30
28
SW 16TH AVE
SW 16 AVE Nl0 SW 23 ST
Local Residential
30
23
SW 16TH AVE V
SW 16 AVE Sl0 SW 23 ST
Local Residential
30
23
SW 23RD TERR
SW 23 TERR E10 SW 16 TERR
Local Residential
30
20
SW 16TH CT
SW 16 CT S/0 SW 23 ST
Local Residential
30
19
SW 16TH CT
SW 16 CT N10 SW 23 ST
Local Residential
30
19
SW 23RD ST
SW 23 ST W/0 SW 16 CT
Local Residential
30
17
SW 14TH AVE
SW 14 AVE S/0 SW 23 ST
Local Residential
30
28
SW 14TH AVE
SW 14 ST N/0 SW 23 ST
Local Residential
30
28
SW 14TH AVE
SW 14 AVE S/0 SW 22 ST
Local Residential
30
28
2.6 Pedestrian and Bicycle Facilities
Sidewalks are provided on all neighborhood streets, however, ADA's ramps are not met
or not provided at all intersections. No bicycle facilities exist. In general, the pedestrian
and bicycle activities within the study area are low and mainly for recreation and
exercise purposes.
2.7 Safety
Appendix A, Figure A4 shows crash location distribution for three years (2001 to 2003)
within the study area. During these three years, 114 vehicle crashes were recorded.
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The Silver Bluff Traffic Calming Study (Final) 8
3.0 NEIGHBORHOOD TRAFFIC MANAGEMENT
3.1 Public Involvement
Community involvement is a key element in the development of any neighborhood
traffic management plan. An intensive public involvement plan was set in motion to this
effect. The public involvement plan included one workshop and one community walk.
Representatives of study area residents were invited to the workshop, where they
addressed the neighborhood traffic problems.
3.1.1 First Workshop
The first • workshop was held on July 29th, 2004 at Coral Way Neighborhood
Enhancement Team Office. During the workshop, the following were presented:
• Concept of Traffic Calming
• State -of -the -Art Traffic Calming Alternatives
• Effectiveness of Traffic Calming Devices
• Traffic Calming Process
• Roadway Function Classification
• Safety Concerns within the Study Area
• Preliminary Traffic Calming Plan
• Residents' Concerns
Records of the first community workshop are presented in Appendix B. The main
concerns of the residents were speeding, traffic intrusion, high crashes, and deficient or
unusual intersection configurations. Residents were allowed a two -week period to
forward additional concerns to the City's Project Manager. A copy of the consultant's
presentation is also documented in Appendix B.
3.1.2 Community Walk
A walk throughout the study area was scheduled with city officials, residents and the
consultant on September 2091, 2004. Residents were given the opportunity to express
their traffic concerns in the field. The consultant explained existing geometrical and
operational problems at several locations and suggested potential traffic calming
alternatives at different locations.
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The Silver Bluff Traffic Calming Study (Final) 9
3.2 Traffic Data Collection
Based on residents and field observations, more than 60 locations were identified for
24-hour volume and speed studies. Three-year crash records were obtained from the
City's Police Department. In addition, the pavement width was field measured for all the
streets within the study area. Appendix A, Figure A5 displays the traffic study
locations within the study area. The summary of the traffic data collection is presented
in Appendix C.
3.3 Traffic Data Analysis Methodology
One of the key elements for the success of any traffic calming program is to identify and
determine the magnitude of the perceived problems. High traffic volume, excessive
speed and high number of accidents have been identified as the main traffic problems.
The magnitudes of existing problems were determined through the review and the
analysis of the traffic data collection. The following data collection methods and
techniques were utilized to gather information for the traffic calming analysis.
Speeding - To ascertain whether a speeding problem exists for a given roadway
segment, a 24-hour speed study was performed at several locations within the study
area. This typically entails measuring each vehicle's speed for the desired time period
(24-hour), and calculating the 85th percentile speed for the traffic stream. This is the
speed below which 85% of the vehicles measured were traveling. When this calculated
value significantly exceeds the desired travel speed for the roadway, then a speeding
problem exists.
High Traffic Volume - If high traffic volume has been identified as the critical traffic
issue for a residential neighborhood; traffic counts for the roadway are required to
determine the magnitude of the problem. The total daily traffic and the AM and PM
peak hour volumes, if needed, are calculated to determine the magnitude of the
problem.
Crash Review - A review of crash records is usually performed to determine the
locations of crashes within the residential neighborhood. This is followed by a field
review to identify the probable causes and to identify appropriate countermeasures.
Access Management - A review of the Florida Department of Transportation (FDOT)
proposed access management plan on SW 27th Avenue is performed during this study.
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The Silver Bluff Traffic Calming Study (Final)
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This access management plan will affect the traffic flow within the residential area. The
detailed traffic turning movement from each local street to SW 27th Avenue is shown in
Appendix A, Figure A6. Some streets will experience a decrease in the volume while
others will experience an increase, Thus, traffic calming devices are being consistent
with the FDOT access management plan.
3.4 Traffic Calming Analysis
The following methodology and selection criteria defined in this study is similar to traffic
calming procedures already established by Miami -Dade County and implemented in
other U.S. cities. The process followed in this study and described below begins with
the petitions from concerned residents.
3.4.1 General Requirements, Constrains and Data Collection
The following requirements and constrains should be taken into consideration to
determine if a street is candidate for a traffic calming study.
• Traffic calming measures will be limited to local residential streets and city
residential collectors.
• The posted speed limit may not be more that 30 mph (local residential streets) or 35
mph (residential collectors).
• Traffic calming measures will be limited to streets with only two lanes of travel.
• Streets must not be used as a primary route for emergency or fire rescue vehicles.
• Traffic calming devices may not be installed if curves or obstacles would create an
unsafe condition for motorists driving at the desired speed limit under normal driving
conditions.
• The street may not be a through truck route, unless an acceptable alternative route
is identified.
• The traffic calming plan shall not adversely affect pedestrians and/or bicycles safety.
• The traffic calming plan should not adversely affect street drainage.
The following data and information for the study area were used for the traffic calming
analysis:
• Roadway functional classification (local residential streets or city residential
collectors)
• Average daily traffic (ADT)
• Traffic speed during an average weekday
• Community centers and schools
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The Silver Bluff Traffic Calming Study (Final)
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• Emergency vehicle routes
• School bus and local bus routes
• Through truck routes
• Alternative routes that traffic may take if Traffic Calming Devices are installed
• Number of crashes
3.4.2 Selection Criteria
The following selection criteria warrants shown in Table 3 can be used to determine
whether a specific location or a segment of a roadway is warranted for traffic calming or
not.
Table 3 - Selection Criteria Warrants
Criteria
Local Residential Streets
Residential Collector
Minimum Volume
> 1,000 vpd
> 2,000 vpd
85« Percentile Speed
10 mph > Posted Speed Limit
10 mph > Posted Speed Limit
Cut -Through Traffic Percentage
25%
50%
Correctable Crashes Per Year
3
6
In this study, the study area boundary exactly matches with the current year Florida
Standard Urban Transportation Model Structure (FSUTMS) Miami -Dade model Traffic
Analysis Zones (TAZs) boundary. The cut -through traffic percentage for the segments
is calculated as follows:
1. Identify the TAZs falls into the study area; which are zone 1055 and 1056.
The TAZ structure in the study area is shown in Appendix A, Figure A7.
2. For each TAZ within the study area, identify year 2005 model forecasted
zonal traffic volume generated by the property (including all types of volume)
within study TAZ, For example, for zone 1056, total zonal daily traffic volume
generated in year 2005 is 7082 vehicles per day.
3. From the street network, identify the number of streets which provide direct
access from one side of the zone to the opposite side of the zone. For
example, for zone 1056, total 14 streets provide such accessibility.
4. Using the total zonal generated traffic volume divide number of streets got
from step 3, thus, average local street carrying volume, which is generated by
local residential properties are calculated. For example, for zone 1056, such
average local street carrying volume should be around 506 vehicles per day.
5. Comparing the existing daily traffic volume with the average local street
carrying volume, if the difference between these two are more than 25% for
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The Silver Bluff Traffic Calming Study (Final)
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local residential street or 50% for residential collector, this location should be
concluded having traffic intrusion problem.
Two of the five warrants must be met before the City will accept a petition from a
neighborhood for a full-scale study. Appendix C shows the results of the traffic calming
selection criteria process for each study zones.
The appropriate traffic calming alternative is then identified, for each location, to solve
existing traffic problem(s).
3.4.3 Scoring and Prioritization System
The prioritization of locations selected for traffic calming measures follows. A scoring
system has been developed to prioritize the warranted location for traffic calming (see
Table 4). Traffic calming projects are then sorted according to their locations where
high scores are given higher priority. Other considerations may be the complexity and
the size of the project, as well as the cost of implementation. Appendix C presents the
prioritization results for all the study location scores.
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The Silver Bluff Traffic Calming Study (Final)
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Table 4 - Scoring System for Prioritizing Warranted Traffic Calming Locations
Category
Points
Assignment
Speed (85th Percentile)
0 - 25
85th Percentile Speed is 50% or more higher than post
speed limit + 10 MPH, 25 points
Less than 50%, ratio of 850 Percentile divided by 1.5 times
of post speed limit + 10 MPH multiples 25
Current Trade-off Volume (vpd)
0 - 25
City Residential Collectors: if volume is 50% or more
higher than 3000, 25 points,
Less than 25%, volume divided by 4500 then multiple 25
Local Residential Street: if volume is 25% or more higher
than 1000, 25 points,
Less than 25%, volume divided by 1250 then multiple 25
Traffic Crash
0 - 25
More than 9 correctable traffic crashes for last 3 years on
the Subject Street: 30 Points
Less than 9 correctable traffic crashes for last 3 years on
the Subject Street: correctable traffic crashes number
multiples 5
Cut -through Percentage
0 - 25
City Residential Collectors: if cut -through percentage is
50% or more higher than 50, 25 points,
Less than 50%, cut -through percentage divided by 3
Local Residential Street: if cut -through percentage is 50%
or more higher than 25, 25 points,
Less than 50%, cut -through percentage divided by 1.5
Total Maximum Points
100
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The Silver Bluff Traffic Calming Study (Final)
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4.0 TRAFFIC CALMING ALTERNATIVES
Due to the emphasis placed on design detail and aesthetic quality within the Silver Bluff
Area, any recommended traffic calming device must meet high aesthetic standards.
Therefore, many of the traffic calming alternatives considered are expected not only to
calm traffic, but also to blend into and accentuate the community landscaping and
aesthetic standards.
4.1 Type of Traffic Calming Measures
Traffic calming is a physical retrofit of traffic operations and management strategies on
existing streets, designed to reduce adverse traffic impacts such as speeding and
excessive volumes and to improve safety and amenity (Weinstein and Deakin, 1998).
There are two types of traffic calming measures, passive traffic control measures and
active traffic control measures.
Passive Control Measures: Passive control devices are the least restrictive and they
do not physically prevent an action. Thus, drivers easily violate the purpose of these
devices when the level -of -service deteriorates during peak periods. Their advantage,
besides their low installation costs, is that they can be enforced during selected time
periods of the day. Examples of the passive control measures are regulatory signs
such as stop signs, speed limit, turn prohibitions, one-way sign, school zone, and Dead
End sign, etc.
Active Physical Control Measures: These are devices that physically restrict drivers
from making a certain movement and force them to change their travel path. They also
create a visual impression that a street is not meant for through traffic and that other
users of the roadway (pedestrians, bicyclists and children) have an equal right to use
the road. Traffic calming alternatives designed to reduce speeding on a roadway
usually involve changes to the geometric character (vertical displacement) of that
particular segment of the road. Changes to the travel path (horizontal displacement) of
the vehicle or perceived width of the roadway typically result in lower speeds because
the motorist is required to attend more to the task of driving. Figure 2 presents different
traffic calming measures classified by purpose.
Marlin Engineering, Inc.
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City of Miami
The Silver Bluff Traffic Calming Study (Final)
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Traffic
Calming
Volume
Control
Measures
Full & Partial Closures
Oiverters
Median Barriers
Forced Turn Islands
Speed
Control
Measures
Active
Speed Control
Moos ures
Vertical
Deflection
Measures
Speed Humps/Tables
Raised Crosswalks
Raised Intersections
Speed Cusions
Horizontal
Deflection
Measures
Roundabouts
Mini Roundabouts
Chicanes
Alternate Side Parking
Realigned Intersection
Center Island Median
Constrictions
Curb Extensions
Neckdowns
Chokers
Slow Points
Gateways
Ped Refuge Islands
Passive
Speed Control
Measures
On -Street Parking
Bicycle Lanes
Narrowed Lanes
Streetscaping
Speed Gun wNMS
Special Signs
Forced Perspective
Rumble Strips
Rumble Stripes
Color Pavement
Textured Pavement
Textured Markings
Figure 2 - Different Traffic Calming Measures Classified by Purpose
A detailed description of selected physical traffic calming measures for the study area
including the advantages and disadvantages of each device is presented in Appendix
B, as part of the Traffic Calming Study Presentation.
4.2 Recommended Traffic Calming Locations
The recommended traffic calming devices and their locations are presented in the
following sections (see Table 5 and Figure 3 through Figure 7). By installing the
recommended calming devices, traffic is expected to slow down within the study area.
The data collection and qualification procedures for recommended traffic calming
devices are shown in Appendix C.
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City of Miami
The Silver Bluff Traffic Calming Study (Final)
16
r
Table 5 - Recommended Traffic Calming Devices by Locations
Street Name
Location(s)
Recommendation
SW 256 Ave'
@ SW 23r4 St., SW 24th Ter., SW 25th Ter., SW 26th
Lane t e
Circles (4)
SW 2441Ave /
./
@ SW 22 �T,er., SW 24th St.., SW 25th St., SW 26th St.,
SW 27th St.' / / f
Circles (5)
SW 23rd Ave.'
@ SW 23rd St., SW 24th Ter., SW 25th Ter.
Circles (3)
@ SW 26th Lane 1
Intersection Improvement tat
SW 280h Lane i
@ SW 27th St. /
Intersection Improvement CO
SW 2181 Ave,-1
@ SW 23rd Ter., SW 24{h Ter., SW 25th St.
Circles (3)
SW 19th Ave.1
@ SW 23rd Sit., SW 24th St`
r
Circles (2)
SW 18th Ave.!
�
@ SW 22nd Ter., SW 234er., SW 24th Ter."
Circles (3)
SW 16th Ct. /
@ SW 23r4 St. )
Circle
SW 14th Ave,
@ SW 23rd St. Ni
Circle
SW 13th Ave. •
@ SW 22"d Ter. /
Circle
SW 3rd Ave.
@SW 23rd Ter. /
Intersection Improvement lc) .•
@SW 23rd St, a,,•
Intersection Improvement le)
@SW 22 Ter -
Intersection Improvement IGl
A „,
@SW 16th Ave. d
Intersection Improvement Idt
(Number of devices recommended to be installed)
(a) See the Figure 4.
(b) See the Figure 5.
(c) See the Figure 6.
(d) See the Figure 7.
Marlin Engineering, Inc.
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SW 22N0 TE
SW 23RD ST
SW 2fTH TE
SW 26TN LA
SW 27TN ST
5W 22ND TE
SW 23R0 5T
Legends
1
Study Area Boundary
Traffic Calming Plan
. chcte
Ina Improvement
FOOT Funclass
11111
MUM
Urban Priipal Arterial
Urban Minor ,arterial
Urban Collector
Urban Local
Local Residential Sheet
Figure 3 - Traffic Calming Plan
for Silver Bluff Area
City of Miami
The Silver Bluff Traffic Calming Study (Final)
18
Figure 4 - Proposed Intersection Improvement at SW 28th Lane & SW 27th St
Figure 5 - Proposed Intersection Improvement at SW 26th Lane & SW 23rd Ave
Marlin Engineering, Inc.
May 25, 2005
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Existing Intersection Condition and Lane Configuration
Proposed Intersection Improvement Plan
�endE
Median
.,
Figure 6 -
RLI
.„
Proposed Access
MINEER!MG Management
Along SW 3rd Avenue 1
Existing Intersection Condition and Lane Configuration
Proposed Intersection Improvement Plan
Expand Existing
Diveder to Make SW
23. ST ES One-way
Entei++g
MARLi
ENGINEERING
Figure 7 -
Proposed Access
Management
V.Along SW 3rd Avenue 2
Existing Intersection Condition and Lane Configuration
Proposed Intersection Improvement Plan
Realign Intersection In PrateGen-
street Parking, No Parking Mein 30' of
Approach to Slop Sign. Cub Bumpoul
So be 30' Back
MAR�!
ENGINEERING -
Figure 8 -
Proposed Access
Management
Along SW 3r4 Avenue 3
Existing Turning Lana
From SW 3itl Avenue to
SW 16. Avenue
Figure 9 -
Proposed Intersection
Improvement at SW 16th
Avenue and SW 311 Avenue
City of Miami
The Silver Bluff Traffic Calming Study (Final)
23
5.0 TRAFFIC CALMING GUIDELINES AND FUNDING STRATEGIES
This section of the report presents a summary of guidelines recommended for the
selection of traffic calming devices, regarding the selection criteria and prioritization
methodology. Also, several funding policies and sources for traffic calming projects are
presented below.
5.1 Guidelines for Traffic Calming Projects
After reviewing several traffic calming policies from other cities, and based on findings
of this study and coordination with the City and Miami -Dade County, the following traffic
calming study process is recommended for the Silver Bluff Area, to process any request
or petition for traffic calming (Figure 6).
1) The traffic calming process starts with receiving petitions from the residents of
specific location(s) or street segment(s), expressing their concerns and
identifying existing problem(s). If the location(s) is on a county or state
roadway, the City will forward their concern to the appropriate agency.
Otherwise, the City will study their concern;
2) General requirements should be met before the City starts with data collection
at the concerned location(s). After data collection, if at least two warrants are
met, the Iocation(s) is considered to be a candidate for a full-scale traffic
calming study;
3) After identifying the possible traffic alternative(s) for the specific location, the
City will score and rank all the candidate projects for funding prioritization;
4) After the City's decision on implementing the project, temporary traffic
calming alternative(s) will be installed at the selected Iocation(s) for a
maximum period of three months;
5) After this period, the City will conduct a post -implementation study to
determine the effectiveness of the devices, If the device(s) does not satisfy
its purpose, the City will try another traffic calming device(s). Otherwise, the
City will install a permanent device(s) at the concerned location.
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The Silver Bluff Traffic Calming Study (Final)
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RCSIdpnts Concerns
Petition
- Problem Identification
Refer to County lNo
or State
Na
Street Network
Classification
re Streets City
Collectors or Residentiat
Streets?
YES
Data Collection
City Residential
Collector
GENERAL REQUIREMENTS & CONSTRAINTS
• Limited la city residential collectors & local residential streets.
• Posted speed iimlt between 30 & 35 mph.
• Limited to streets with only two lanes of travel,
• Streets are not primary emergency routes.
• May not be installed If curved streets would create an unsafe
condition.
• Streets are not a truck route.
• No adverse effect an pedestrians and/or bicycles safely.
• No adverse effect on street drainage.
Local Residential
Street
• Traffic Volume' > 2,000 vpd
• 85th Percentile Speed > 10 mph over
posted Speed Limit
• Cut -Through Traffic> 50%
• Pedestrian Volume > 50 pph
• Correctable Accidents > 6/year
Warrants
• Traffic Volume' > 1,000 vpd
• 85th Percentile Speed > 10 mph
over posted Speed Limit
• Cut -Through Traffic > 25%
• Pedestrian Volume > 25 pph
• Correctable Accidents > 3/year
No
Remove Device
&
Test Another
YES
Identify Traffic
Calming
Alternatives
Project Scoring and
Ranking
Installation of
Temporary Devices
Post -Implementation
Study
Is Device
Effective?
PRIORITIZATION & SCORING
SYSTEM
Qategory point*
Speed (85th %) 0. 25
Current Vol. (vpd) 0. 25
Traffic Crash 0.25
Cul-through Traffic percentage 0.25
Total Points (max,) 100
'Detailed scoring calculation please see
report Table 4
YES
INSTALL
PERMANENT
DEVICE
Figure 10 - Recommended Traffic Calming Study Process
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The Silver Bluff Traffic Calming Study (Final)
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5.2 Funding Strategies
Funding for traffic calming is a key issue with many local governments. Traffic calming
installations often require the city staff to invest time in preparing design and
construction specifications. Moreover, costs for planning and citizen involvement in
many cases exceed construction costs for some traffic calming installations. In addition,
in some cases it is preferred to hire a consultant rather than assign local staff to do
planning and design work.
5.2.1 Local Funds
In a survey conducted by Weinstein and Deakin in 1999 as part of a research study
entitled "How Local Jurisdictions in the United States Finance Traffic Calming?" the
following was concluded.
• Some local governments pay for all traffic calming, on the grounds that mitigation of
the adverse impacts of auto travel is an appropriate city responsibility, under the fact
that residents have the right to live on quiet streets.
• In other cases, traffic calming is seen as a public responsibility when the problem is
severe, but a private benefit when it is milder.
• Cost -sharing approach is often used on a sliding scale according to the degree of
severity.
• It was also reported that the locality will pay for basic treatment but the residents will
pay for the costs of amenities such as landscaping or upgraded materials.
• Finally, some jurisdictions require residents to pay all the costs as a way to limit
traffic calming requests.
In the latest publication from Institute of Transportation Engineers (ITE) "Traffic
Calming: State of the Practice" it is concluded that anticipated applicants petitioning for
the implementation of traffic calming measures may be requested to participate in the
funding of the project process starting from traffic studies through construction.
Willingness of the residents to directly participate in the funding of traffic calming
measures may be the ultimate test of public support. However, there is debate over the
appropriate level of cost sharing, whether the level should vary with the circumstances,
and what circumstances are relevant.
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The Silver Bluff Traffic Calming Study (Final)
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Many featured programs offer cost -sharing options. A few programs have sought to
further local policies and priority by placing neighborhoods' share of costs on sliding
scales. Table 6 presents some creative cost -sharing formulas based on project
priority ratings, for several cities in the United States.
Landscaping adds a substantial increment to the cost of constructing traffic calming
measures. Thus, several cities in the United States came out with different landscaping
maintenance policies. The concept of most of these policies is that the City installs the
traffic calming measure and the neighborhood pay for the maintenance. Table 7
presents examples of different policies for landscaping maintenance programs.
Finally, the cost of traffic calming measures can be paid by developers in an existing
neighborhood, as part of the development approval process. Several jurisdictions have
identified traffic generated by a specific development as a negative environmental
impact that the developer must mitigate. Still few jurisdictions are now making the
evaluation of neighborhood traffic impacts a formal part of their development reviews
and are frequently assessing fees or requiring specific actions for traffic calming
(Weinstein and Deakin, 1999). For example, the development review committee in
Sarasota, FL, looks at impacts on nearby neighborhoods, utilizing data from impact
studies required of all development applications and an impact fee of $10,000 are
typically required. Los Angeles acquired a significant amount of money for traffic
calming from developers and expects this to become more frequent in the future.
Table 6 - Examples of Local Funds Including Cost -Sharing Programs
Location
Neighborhood Share
Basis for Neighborhood Share
Austin, TX
0-100% (sliding scale, based on point
score)
Priority of project (discontinued)
Boca Raton, FL
0% and up
Incremental cost of more elaborate
measures
Boulder, CO
50% (high priority)
100% (low priority)
Priority rating of project
Charlotte, NC
0% and up
Incremental cost of more elaborate
measures
Source: Traffic Calming: State of the Practice, 1TE, 1999.
Marlin Engineering, Inc.
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The Silver Bluff Traffic Calming Study (Final)
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Table 7 - Examples of Landscaping Maintenance Policies
Community
Policy
Dayton, OH
City installs - neighborhoods maintain
Eugene, OR
City installs - neighborhoods originally maintain but city assume
function when volunteer efforts end
Gainesville, FLCity
offers two options: free Xeriscape or plants of choice from city
nursery - city installs - neighborhoods maintain
Howard County, MD
County installs and maintains
Montgomery County, MD
Neighborhoods choose from approved list - county installs -
neighborhoods maintain
San Diego, CA
Neighborhoods choose landscape palette - city install - neighborhoods
maintain
Tallahassee, FL
Neighborhood install and maintain - policy is being reconsidered in
light of "uglies"
Source: Traffic Calming: State of the Practice, ITE, 1999.
5.2.2 Non -Local Funds
Federal Funds - Very few jurisdictions reported the use of federal funds for traffic
calming purposes. The fund received was from the Department of Housing and Urban
Development (HUD) rather than the Department of Transportation (DOT). Other
jurisdictions reported the use of Community Development Block Grant (CDBG) in
funding traffic calming. Local housing and redevelopment funding also is used
occasionally. For example, in Bridgeport, CT, the local housing authority paid for a
small amount of traffic calming in one of its projects.
Additional Funding Sources - Several cities have utilized additional sources of
funding for traffic calming. Table 8 summarizes other additional non -local funding
sources and their allocations for each city.
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The Silver Bluff Traffic Calming Study (Final)
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Table 8 - Examples of Non -Local Funds
Funding Source
City, State
Purpose
Federal Funds
Bridgeport, CT
Local Housing Authority paid for part of traffic calming
for one project
State Grants
Phoenix, AZ
State grant to pay for traffic counts and for presentation
equipment for public meetings
Sacramento, CA
Grants from the State Office of Traffic Safety and School
Safety Education to support neighborhood traffic
management program
Seattle, WA
Grants for hazard elimination to fund traffic calming
projects, including pedestrian improvements
Several Cities, OR
State transportation and growth management funds
administered by DOT to fund traffic calming
Bond Finance
Seattle, WA
1968 bond measure to renew deteriorating neighborhood
used to Fund traffic calming
Albuquerque, NM
Voter approved $100,000 bond issue for traffic calming
and additional bond initiatives have been proposed.
Tax Increment
Finance
Fresno, CA
Tax increment funds were used to pay for semi-diverters
installed as part of a redevelopment project
Minneapolis, MN
Excess tax -increment money to fund Neighborhood
a
Revitalization Program. (49% for traffic calming)
Source: "Now Local Jurisdictions in the United States Finance Traffic Calming", Weinstein and Deakin
1999.
5.2.3 Funding Policies
As a reference, the City of Coral Gables currently has a policy for traffic flow
modification (Appendix D). The policy mandates that applicants for traffic calming
projects should participate in all the associated costs, in addition to the costs of
landscaping and maintenance. The past experience of the City shows that residents
are willing to share the cost of the implementation. For existing street closures, traffic
studies were conducted by the City and residents paid for the installation of the
temporary and permanent barricades. Also, applicants for closure are responsible for
the maintenance of the closure area. Moreover, in case an additional traffic study is
needed or any additional engineering is required, the applicant must pay for all the
associated cost. It is recommended for the City of Miami to define a funding policy once
a decision on the appropriate funding strategy has been taken.
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The Silver Bluff Traffic Calming Study (Final)
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6.0 RECOMMENDATIONS
This report documents the City of Miami Silver Bluff Area Traffic Calming Study and
addresses traffic problems in selected locations with public concerns related to
speeding, accidents and traffic intrusions. Also, the report provides the City with a
methodology to warrant and prioritize traffic calming projects, and potential funding
sources. The study process, the requirements and constraints, and selected projects
recommended for implementation have been presented in this study for the City's
review and commissioners' approval. Table 9 shows the estimated cost for
implementing traffic calming devices within the study area. Typical design drawings for
recommended traffic calming devices are presented in Appendix E.
Table 9 - Cost Estimate of Recommended Traffic Calming Devices
Type of Device
Total Number
Unit Cost
Estimated Cost
Traffic Circles
23
$ 15,000
$ 345,000
Intersection Improvements
6
$ 20,000
$ 120,000
Total
$ 465,000
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The Silver Blaff Traffic Calming Study (Final)
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REFERENCES
• Atkins, Crysttal, and Michael Coleman. The Influence of Traffic Calming on
Emergency Response Times. ITE Journal, Institute of Transportation Engineers,
Washington, D.C., August, 1997, pp. 42-47.
• Castellone, Anthony J., and Muhammad M. Hasan. Neighborhood Traffic
Management: Dade County, Florida's Street Closure Experience. ITE Journal,
Institute of Transportation Engineers, Washington, D.C., January, 1998, pp. 28-32.
• Ewing, Reid, Edith McClintock and Richard A. Hall. U.S. Experience with Traffic
Calming. Institute of Transportation Engineers, International Conference, Tampa,
FL, March, 1997, pp. 16-20.
• Ewing, Reid, and Charles Kooshian. Traffic Calming Measures: What, Why, Where,
and How. Transportation Research Board 78th Annual Meeting, Washington, D..C.,
January, 1999.
• Hoyle, Cynthia L. Traffic Calming. American Planning Association, Planning
Advisory Service, Report Number 456, July, 1995.
• J.P. Braaksma & Associates Ltd., 1995. Reclaiming the Streets: Setting the Stage
for a Traffic Calming Policy in Ottawa. Proceeding of a Symposium: Calming
Cascadia, Victoria, B.C., Canada, September, 1995.
• Leonard, John, and W. Jeffrey Davis. Urban Traffic Calming Measures
Conformance with AASHTO and MUCTD Guidelines. Conference proceedings:
Traffic Congestion and Traffic Safety in the 21st Century Challenging, Innovations,
and Opportunities, ASCE, Chicago, IL, June, 1997, pp. 14-20.
• Leonard, John, and W. Jeffrey Davis. Urban Traffic Calming Measures
Conformance with AASHTO and MUCTD Guidelines. Conference proceedings:
Traffic Congestion and Traffic Safety in the 21st Century Challenging, Innovations,
and Opportunities, ASCE, Chicago, IL, June, 1997, pp. 14-20.
Marlin Engineering, Inc.
May 25, 2005
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The Silver Bluff Traffic Calming Study (Final)
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• Lockwood, Ian A. ITE Trafif Calming Definition. ITE Journal, Institute of
Transportation Engineers, Washington, D.C., July, 1997, pp. 22-24.
• Neighborhood Traffic Management Program. Miami -Dade County Public Works
Department, Highway Division, Traffic Engineering Section, Miami, FL, 1999.
• Neighborhood Traffic Management and Calming Program. City of San
Buenaventura, Department of Community Services, Engineering Division 01 Poll
Street, Ventura, CA 93001, June, 1997.
• Weinstein, Asha and Elizabeth Deakin, 1998. A Survey of Traffic Calming Practices
in the United States. University of California at Berkeley, March, 1998.
• Street Closure/Traffic Flow Modification Study. Dade County Public Works
Department, Metropolitan Planning Organization, Miami, FL, 1996.
• Traffic Calming Program. City of Portland, Oregon, 1999.
• Traffic Calming: State -of -the -Practice. Institute of Transportation Engineers,
Washington, D.C., 1999.
• Citywide Traffic Study -Calming and Mitigation. City of Coral Gables, FL, 1999.
Marlin Engineering, Inc.
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