CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on October X, 2024 DRAFT
CITY OF COMMERCE
2024 ENGINEERING
AND TRAFFIC SURVEY
CVC SECTION 627
Adopted by Commerce City Council
Resolution No. XX on December X, 2024
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CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
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TABLE OF CONTENTS
SECTION PAGE
Cover Page i
Table of Contents ii
Commerce City Council Adopted Resolution No. XX (Adopted November X, 2024) iii Preparer’s Certification (Engineer’s Stamp and Signature) v Section 1: Introduction
✓ Table 1: List of Segments in Speed Survey
1 Section 2: Overview 2
✓ California Vehicle Code 2
✓ Local Authority to Establish Prima Facie Speed Limits 3 ✓ Speed Trap 3
✓ Engineering and Traffic Survey 4
✓ California Manual on Uniform Traffic Control Devices 5 ✓ Data Collection 6
✓ Procedures 7
Section 3: Summary of Recommendations 9
✓ Table 2: City of Commerce 2024 Engineering and Traffic Survey Summary 10 Section 4: City of Commerce 2024 Citywide Speed Limit Map and Average Daily Traffic (ADT) Map 11
✓ City of Commerce 2024 Citywide Speed Limit Map 12
✓ City of Commerce 2024 Citywide Average Daily Traffic (ADT) Map 13 Section 5: Engineering and Traffic Survey Summary Forms 14 Section 6: Average Daily Traffic (ADT) Counts 29
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
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DRAFT RESOLUTION NO. XXXX
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF
COMMERCE, CALIFORNIA, APPROVING THE CITY OF COMMERCE’S 2024
ENGINEERING AND TRAFFIC SURVEY (SPEED SURVEY)
WHEREAS, pursuant to the California Vehicle Code Section, the City completed an Engineering and Traffic Survey (ETS) for 7 street segments citywide attached herein as Attachment A; and WHEREAS, the purpose of the ETS is to establish updated speed limits that can be legally enforced using radar at pre-determined locations; and
WHEREAS, the adoption of the City of Commerce’s 2024 ETS attached herein as (Attachment A) will allow the posted speed limit to be upheld by the courts and does not constitute a "Speed Trap" as defined by CVC Section 40802; and
WHEREAS, state and local agencies should conduct ETS at least once every 5, 7, or 14 years, in compliance with the California Vehicle Code (CVC Section 40802) to reevaluate non-statutory speed limits on segments of their roadways.
WHEREAS, ETS can be an enforceable document for a maximum of 14 years as long as there have not been any significant changes in the roadway; and WHEREAS, approval of the City’s ETS is required to establish citywide speed limits to be upheld by the courts; and
WHEREAS, the recommended speed limits are consistent with the prevailing behavior as demonstrated by the radar speed measurements; and
WHEREAS, based on the results of the ETS, one (1) of the studied segments’ speed limits will be lowered by 5 mph due to existing conditions, land use and collision rates; and WHEREAS, the recommendation contained in the ETS were intended to establish prima facie speed limits. Prima Facie limits advise the motorists and enforcement agencies of the reasonable speed for a section of highway for prevailing conditions.
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
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THE CITY COUNCIL OF THE CITY OF COMMERCE HEREBY RESOLVES AS FOLLOWS:
Section 1. The foregoing recitals are true and correct and are incorporated herein as if set forth in full.
Section 2. The City of Commerce 2024 Engineering and Traffic Survey for 7 street segments Citywide for the establishment of speed limits attached herein as Attachment A is hereby approved and adopted.
Section 3. This Resolution shall become effective immediately upon its adoption.
Section 4. The City Clerk is directed to certify the adoption of this Resolution.
SIGNED, APPROVED AND ADOPTED THIS DAY OF XX.
___________________________________
HUGO A. ARGUMEDO, Mayor
ATTEST:
LENA SHUMWAY, City Clerk
I HEREBY CERTIFY that the above and foregoing resolution was duly passed and adopted by the Commerce City Council, its adjourned regular meeting held on the XX day of XXX, 2024, by the following vote, to wit:
AYES:
NOES:
ABSENT:
___________________________________
LENA SHUMWAY, City Clerk
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
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PREPARER’S CERTIFICATION
CITY OF COMMERCE, CALIFORNIA
ENGINEERING AND TRAFFIC SURVEY
CVC SECTION 627
EFFECTIVE DATE: NOVEMBER X, 2024
ADOPTED BY COMMERCE CITY COUNCIL RESOLUTION NO. XX ON NOVEMBER X, 2024 This report was prepared under the supervisions of:
Okan Demirci, PE
CERTIFICATION BY ENGINEER
__________________________
Okan Demirci, PE
License Type: Registered Professional Engineer
License Number: 90039
CERTIFICATION BY ENGINEER
I, Okan Demirci, contracted Traffic Engineering, do hereby certify that the November 2024 Engineering and Traffic Survey for the City of Commerce was performed under my supervision. I certify that I am both experienced in performing surveys of this type and am duly registered in the State of California as a professional Engineer. The survey has been conducted in strict compliance with guidelines contained in the California Vehicle Code and the California Manual on Uniform Traffic Control Devices. Data contained in this report represents a true and accurate description of traffic conditions existing on City of Commerce Streets. 06/30/25
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
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DRAFT
SECTION 1: INTRODUCTION
The purpose of this report is to prepare an Engineering and Traffic Survey at pre-determined locations in the City of Commerce to establish updated speed limits that can be enforced using radar. An Engineering and Traffic assessment was prepared for 7 street segments in the City of Commerce. Applicable sections of the California Vehicle Code (CVC) and Department of Transportation California Manual on Uniform Traffic Control Devices (CAMUTCD), as Revision 7 March 2023, have been followed so that the posted speed limits can be upheld by the courts and do not constitute a "Speed Trap" as defined by CVC Section 40802. The following table lists all of the street segments considered in the 2024 City-Wide Speed Survey.
SEGMENT SUMMARY
Table 1
List of Segments
No. Street Segment Roadway Classification
1. Atlantic Boulevard Washington Boulevard to Harbor Street Other Principal Arterial
2. Atlantic Boulevard Harbor Street to Goodrich Boulevard Other Principal Arterial
3. Commerce Way Eastern Avenue to Washington Boulevard Major Collector
4. Eastern Avenue Harbor Street to Sheila Street Other Principal Arterial
5. Eastern Avenue Sheila Street to Commerce Way Other Principal Arterial
6. Ferguson Drive Gerhart Avenue to East City Limit Major Collector
7. Triggs Street Marianna Avenue to McDonnell Avenue Major Collector Each of these segments are classified and defined with roadway classifications as listed in the California Road Systems (CRS) Maps that are approved by the Federal Highway Administration and maintained by the Department of Transportation (CVC 40802). Functional classifications are used in determining which type of roads are eligible for Federal funding to maintain the roads.
Usually Principal Arterials, Minor Arterial and Major Collectors are eligible.
Functional classification is the process by which streets and highways are grouped into classes, or systems, according to the character of service they are intended to provide. Basic to this process is the recognition that individual roads and streets do not serve travel independently in any major way. Rather, most travel involves movement through a network of roads. Functional classification defines how a particular road or street plays in serving the flow of trips through a highway network.
The four functional systems for urbanized areas are urban principal arterials, minor arterials, major collectors, and local roads.
Principal Arterials: Major Arterials carry most of the trips entering and leaving the City as well as serves the major centers of activity of a City, carries the highest traffic volume along its corridors while carrying the major portion of trips entering and leaving the urban area.
Minor Arterials: The minor arterial street system includes all arterials not classified as principal and contains facilities that place more emphasis on land access than the higher system and offer a lower level of traffic mobility. Such facilities may carry local bus routes and provide intracommunity continuity, but ideally should not penetrate identifiable neighborhoods. This system CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
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should include urban connections to rural collector roads where such connections have not been classified as urban principal arterials.
Major Collectors: The collector street system provides both land access service and traffic circulation within residential neighborhoods, commercial and industrial areas. It differs from the arterial system in that facilities on the collector system may penetrate residential neighborhoods, distributing trips from the arterials through the area to the ultimate destination. Conversely, the collector street also collects traffic from local streets in residential neighborhoods and channels it into the arterial system.
Local Roads: These roadways provide direct access to individual residential properties, schools, and churches typically with a posted speed of 25 MPH. Through traffic on local streets are usually discouraged. Local roads within residential and business district zones are not subject to Speed Trap provisions and are posted at the Prima Facie speed limit. Service to through traffic movement is usually deliberately discouraged.
SECTION 2: OVERVIEW
CALIFORNIA VEHICLE CODE:
Speed limits in California are governed by the California Vehicle Code (CVC), Sections 22348 through 22413. The statutes establish or provide means of establishing speed limits by:
1. Basic speed limit law.
Section 22350 of the CVC provides that no person shall drive a vehicle upon a highway at a speed greater than is reasonable or prudent having due regard for weather, visibility, traffic and the surface and width of the highway, and in no event at a speed which endangers the safety of persons or property. This is the basic speed limit law.
2. Prima facie speed limits are specified by statute or established by the State or local authorities within their respective jurisdictions on the basis of an engineering and traffic survey. Prima facie speed limits are specific limits stated in the CVC or specific limits established on the basis of an engineering and traffic survey authorized by the CVC. Prima facie speed limits are preempted by the basic speed limit law when the conditions in CVC Section 22350 are met.
Section 22352 of the CVC establishes prima facie speed limits as follows and shall be applicable unless changed as authorized in the CVC and if so changed, only when signs have been erected giving notice of the change:
a. Fifteen miles per hour.
• At a railroad grade crossing with an obstructed view. • At an uncontrolled highway intersection with an obstructed view. • In an alley.
b. Twenty-five miles per hour.
• On any highway other than a State highway, in any business or residence district, CVC CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
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Sections 235 and 515 define a "business district” and a “residence district” respectively.
Section 240 of CVC prescribes a method for determining whether a highway is within a business or residence district.
• Unless a different limit is established by procedures described elsewhere in the code. • In a school zone, posted with SCHOOL warning signs.
• When passing a facility primarily used by senior citizens and contiguous to a street other than a State highway and posted with a SENIOR warning sign.
Increase of local speed limits to 65 miles per hour
Section 22357.
(a) Whenever a local authority determines upon the basis of an engineering and traffic survey that a speed greater than 25 mph would facilitate the orderly movement of vehicular traffic and would be reasonable and safe upon any street other than a state highway otherwise subject to a prima facie limit of 25 mph, local authorities may by ordinance determine and declare a prima facie speed limit of 30, 35, 40, 45, 50, 55 or 60 mph or a maximum speed of 65mph, whichever is found most appropriate to facilitate the orderly movement of traffic and is reasonable and safe. The speed limit shall become effective when signs are installed on the street and not revised unless justified on the basis of an engineering and traffic survey.
LOCAL AUTHORITY TO ESTABLISH PRIMA FACIE SPEED LIMITS:
Sections 22357 and 22358 of CVC authorize local authorities to establish prima facie speed limits on streets and roads under their jurisdiction on the basis of an engineering and traffic survey. The declared prima Facie limits shall become effective when appropriate signs giving notice are erected upon the street.
SPEED TRAP:
Section 40802 2B(i) of the CVC provides that prima facie speed limits established under Sections 22352, 22354, 22357, 22358 and 22358.3 may not be enforced by radar unless the speed limit has been justified by an engineering and traffic survey conducted within one of the following time periods; five years to the date of the violation, within the last 7 years or if an engineering and traffic survey was conducted more than 7 years prior to the date of the alleged violation, and a registered engineer evaluates the section of the highway and determines that no significant changes in roadway or traffic conditions have occurred, including, but not limited to, changes in adjoining property or land use, roadway width, or traffic volume, the survey applies for 14 years.
The CAMUTCD Revision 7 and CVC Section 40802 has been formally adopted by the State, in June of 2024, the engineering and traffic survey may be extended to 14 years, using the same prerequisites.
This section does not apply to local streets, roads or school zones which have been set at the Prima Facie speed limit. Local streets are defined to have the following characteristics:
• Width not more than 40 feet
• Not more than .5 miles of uninterrupted length
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• 1 lane in each direction
CVC Section 515. A residence district is that portion of a highway and the property contiguous thereto, other than a business district, (a) upon one side of which highway, within a distance of a quarter of a mile, the contiguous property fronting thereon is occupied by 13 or more separate dwelling houses or business structures, or (b) upon both sides of which highway, collectively, within a distance of a quarter of a mile, the contiguous property fronting thereon is occupied by 16 or more separate dwelling houses or business structures.
Those segments classified as a local street in the California Road System and are in a residential district have a prima facie speed limit of 25 mph and are not typically included in engineering and traffic studies.
ENGINEERING AND TRAFFIC SURVEY:
Section 627 of CVC defines the term engineering and traffic survey and lists its requirements.
Section 627 states: "An engineering and traffic survey shall include, among other requirements deemed necessary by the Department of Transportation, consideration of all of the following:
prevailing speeds as determined by traffic engineering measurements; accident records; highway traffic and roadside conditions not readily apparent to the driver." The Engineering and Traffic Survey should contain sufficient information to document that the conditions of CVC Section 627 have been complied with and that other conditions not readily apparent to motorists are properly identified.
In determining the speed limit, which most appropriately facilitates the orderly movement of traffic and is reasonable and prudent, crucial factors such as prevailing speeds, unexpected conditions, and collision records are examined.
Determination of posted speed limits follow the latest CAMUTCD Policy as Revision 7 March, 2023 by the State of California Department of Transportation. Speed limits shall be rounded to the nearest (5 MPH) increment of the 85th percentile speed of free-flowing traffic. However, in cases in which the speed limit needs to be rounded up to the nearest five miles per hour increment of the 85th percentile speed, the Department of Transportation or a local authority may decide to instead round down the speed limit to the lower five miles per hour increment, but then the Department of Transportation or a local authority shall not reduce the speed limit any further for any reason CVC 21400(4)(b).
An example of the application of this speed limit criteria is as follows:
• If the 85th percentile speed in a speed survey is (37 MPH) then the speed limit would be posted at 35 MPH or optionally reduced to 30 MPH. However, • If the 85th percentile speed in a speed survey is (38 MPH) then the speed limit would be posted at 40 MPH or optionally reduced to 35 MPH.
The 85th percentile speed is often referred to as the critical speed. Pace speed is defined as the 10-mile increment of speed containing the largest number of vehicles. Speed limits established on CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
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the basis of the 85th percentile conform to the consensus of those who drive highways as to what speed is reasonable and prudent and are not dependent on the judgment of one or a few individuals.
Basic speed law states that no person shall drive at a speed greater than is reasonable or prudent.
The majority of drivers comply with this law. Speed limits set at the 85th percentile speed provide law enforcement officers with a means of controlling drivers who will not conform to what the majority considers reasonable and prudent.
When roadside development results in traffic conflicts and unusual conditions which are not readily apparent to drivers, speed limits somewhat below the 85th percentile may be justified.
CALIFORNIA MANUAL ON UNIFORM TRAFFIC CONTROL DEVICES (CAMUTCD):
Section 2B.13 CAMUTCD: Reduction of 85th Percentile Speed by Justification of an Engineering and Traffic Study and Approved by a Civil or Traffic Engineer.
Standard:
12a: When a speed limit is to be posted, it shall be established at the nearest 5 MPH increment of the 85th-percentile speed of free-flowing traffic, except as shown in the Option below.
Option:
The posted speed may be reduced by 5 MPH from the nearest 5 MPH increment of the 85thpercentile speed, in compliance with CVC Sections 627 and 22358.5. See Standard below for documentation requirements.
Standard:
12b: If the speed limit to be posted has had the 5 MPH reduction applied, then an E&TS shall document in writing the conditions and justification for the lower speed limit and be approved by a registered Civil or Traffic Engineer. The reasons for the lower speed limit shall be in compliance with CVC Sections 627 and 22358-22358.5.
Support:
12c: The following example is provided to explain the application of this speed limit criteria:
A. If the 85th percentile speed in a speed survey for a location was 37 MPH, then the speed limit would be established at 35 MPH since it is the closest 5 MPH increment to the 37 MPH speed. As indicated by the option, this 35 MPH established speed limit could be reduced by 5 MPH to 30 MPH if the conditions and justification for using this lower speed limit are documented in the E&TS and approved by a registered Civil or Traffic Engineer.
The fundamentals used to establish speed limits recognize that the majority of drivers behave in a safe and reasonable manner but need to be advised of conditions which may not be readily apparent. For this reason, collision history, roadway conditions, traffic characteristics, and land use must be analyzed along with speed measurements to determine speed limits. Speed limit CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
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changes are usually coordinated with visible changes in roadway conditions or roadside developments.
In general, speed limits cannot be successfully enforced without voluntary compliance by a majority of drivers. Consequently, only the driver whose behavior is clearly out of line with the normal flow of traffic is considered a violator for enforcement purposes.
DATA COLLECTION:
Data was obtained regarding the prevailing speed of vehicles, traffic collisions, visibility restrictions, roadway conditions, pedestrian activities, on-street parking, and land use adjacent to the roadways. Radar speed measurements were conducted during the month of July 2024. On the segment of Eastern Avenue from Harbor Street to Sheila Street, the radar was taken in October of 2024 due to a change in roadway conditions.
Highway, traffic, and roadside land uses were analyzed for conditions not readily apparent to motorists. The criteria and procedures described below were applied when using the electronic radar to measure vehicle speeds on selected streets within the City of Commerce. Traffic volume and speed in both directions were recorded.
The hours of radar operation were restricted to off-peak period for heavily traveled streets, and to non-congested peak periods on lightly traveled streets on a weekday. The radar measurements were taken from an unmarked vehicle so as not to alter or impede the free flow of traffic.
A total of 100 samples were obtained for each street segment surveyed, where possible. In no case were sample sizes less than 50 vehicles for each direction. For lower volume streets, samples of free-flowing speeds were taken over several periods/days in order to gather the required survey samples.
Collision data was obtained from the computerized accident records system maintained by the State of California Statewide Integrated Traffic Records System (SWITRS). For purposes of this study, information available for the most recent 4.0-year period was used to develop the collision statistics as a part of the Engineering and Traffic Surveys. Collision data was obtained for the years of January of 2020 to December 2023.
Average Daily Traffic (ADT) data at all (7) locations were obtained from counts taken by a private traffic counting firm in August 2024. These counts were taken while school was in session. Any unusual counts were checked and redone in order to verify the amount of traffic each segment carries. The ADT counts were taken by NDS Services.
National Data & Surveying Services
8370 Wilshire Blvd. Ste, 205
Beverly Hills, CA 90211
Tel (323) 782-0090
www.ndsdata.com
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PROCEDURES:
The radar equipment used to collect speed measurements was a SCOUT-MPH Traffic Radar, SHD04287 serial number, manufactured by Decatur. The unit was calibrated before each series of measurements were taken. Tests of the unit were conducted in accordance with the manufacturer’s specifications.
The results of the radar speed measurements were computed, analyzed, and summarized on standard Traffic Survey Forms. Significant values obtained from computations are as follows:
• The Critical Speed or 85th percentile speed, is that speed at which 85 percent of the traffic is moving. The Critical Speed is the primary guide in determining what the majority of drivers believe is safe and reasonable. Speed limits set higher than the Critical Speed are not considered reasonable and safe. The accepted practice is to set the speed limit at the nearest 5 MPH increment to the Critical Speed or 85th percentile speed unless other factors require a lower limit.
• The 5 or 10 MPH pace is a measure of the dispersion of speeds within the survey sample and is that 5 or 10 MPH increment containing the highest percentage of speeds in the total sample. The accepted practice is to keep the speed limit within the 10 MPH pace after considering the Critical Speed and any factors requiring a speed lower than the Critical Speed.
The collision data for each street segment was compared to collision rates that can be reasonably expected to occur on streets and highways of the same characteristics. These anticipated collision rates have been developed by Caltrans and are applicable for use in the City of Commerce. The collision rates used for this study are as follows Current collision rates are shown in terms of “accidents per 1,000,000 vehicle miles of travel” for each segment. The rate was calculated for each segment using the following formula:
CALIFORNIA STATE HIGHWAYS
STATEWIDE TRAVEL AND COLLISION RATES*
URBAN (Inside City)
2 and 3 lanes
4 or more undivided
4 or more divided
EXPECTED COLLISION RATES
1.69 0.82
0.89 *Source: 2021 Prepared 2023 Crash Summary for District 7 on California State Highways published by State of California, Business, Transportation and Housing Agency, Department of Transportation, Division of Traffic Operations CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
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The Crossroads Software Collision Program calculated the collision rate for each segment.
As previously indicated, speed limits are usually set at or near the Critical Speed unless there are other factors not readily apparent to a reasonable motorist which may justify a lower limit. The field review of the selected street segments in the City of Commerce considered the following factors:
1. Street width and alignment.
2. Pedestrian activity and traffic flow characteristics.
3. Number of lanes, and other channelization and striping patterns.
4. Frequency of intersections, driveways, and on-street parking.
5. Location of stop signs, traffic signals, and other regulatory traffic control devices.
6. Visibility obstructions.
7. Land use and the proximity of schools.
8. Uniformity with existing speed zones in adjacent jurisdictions.
9. Any other unusual condition not readily apparent to the driver.
10. Location of any uncontrolled Crosswalks.
11. Bike lanes, bike routes.
COLLISION RATE = (N x 5,280 x 1,000,000)/ (ADT x L x Y x 365) N: number of collisions within the study segment
ADT: average daily traffic volume
L: length of segment in feet
Y: number of years of accident history
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SECTION 3: SUMMARY OF RECOMMENDATIONS
The Engineering and Traffic Survey summaries presented in this report illustrate the results of a thorough evaluation of the data collected and provides a recommended speed limit for each street segment surveyed. In each case, the recommended speed limit is consistent with the prevailing behavior as demonstrated by the radar speed measurements.
The Legislature, in adopting Section 22358.5 of the California Vehicle Code, has made it clear that it is their intent that physical conditions such as width, curvature, grade and surface conditions, or any other condition readily apparent to a driver, in the absence of other factors, would not require special downward speed zoning. The basic rule of Section 22350 is sufficient regulation as to such conditions.
The recommendations contained in this report were intended to establish prima facie speed limits.
Prima Facie limits advise the motorist and enforcement agencies of the reasonable speed for a section of highway for prevailing conditions. They are not intended to be absolute. All violations of these speed limits are violations of the basic speed law (Section 22350 of California Vehicle Code). This statute states that a person shall not drive a vehicle as a speed greater than is safe having regard for traffic, roadway, and weather conditions. A prima facie limit merely suggests a safe speed under normal conditions.
Out of the above 7 segments surveyed, based on the 2024 Engineering and Radar Speed survey results, it was determined that one (1) of the speed limits on the studied segments is proposed to be changed.
Ferguson Drive between Gerhart Avenue and the East City Limit (east of Concourse Avenue), justifies a 5-mph reduction in the existing speed limit from 30 mph to 25 mph based on roadway conditions. Although Ferguson Drive is classified as a collector, several segments along Ferguson are lined with single family units. Traffic calming measures such as speed humps and side stripes have been installed to combat speeding vehicles. Parking is very dense on both sides of the street with pockets for manufacturing with trucks in the mix. There are also all-way stops at regular intervals along the segment.
The following Table 2 provides a summary of each of the segments included in the engineering and traffic survey indicating the existing posted speed limit, ADT, number of collisions, collision rates, 85th percentile speed, change in limit and proposed 2024 speed limit.
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
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Table 2 City of Commerce 2024 Engineering and Traffic Survey Summary Adopted by Commerce City Council Resolution No. XX on November X, 2024 ID Primary
Location
Limits
Street Class.
(A)
Posted
Speed
2024
ADT
No.
of
Acc.
in
4.0/yr
per.
Collision
Rate
Expected
Collision
Rate
85%
Speed
10 MPH
Pace
Limit
Per
85% Change
in Limit?
Yes/No
Adopted
2024
Speed
Limit
Beginning Ending
1 Atlantic
Boulevard
Washington
Boulevard
Harbor
Street
Other
Principal
Arterial
40 23277 31 3.021 0.89 43.9 35-
44 40 No 40
2 Atlantic
Boulevard
Harbor
Street
Goodrich
Boulevard
Other
Principal
Arterial
40 24814 33 1.807 0.89 43.1 35-
44 40 No 40
3 Commerce
Way
Eastern
Avenue
Washington
Boulevard
Major
Collector 35 5053 5 2.845 0.82 38.9 31-
40 35 No 35
4 Eastern
Avenue
Harbor
Street
Sheila
Street
Other
Principal
Arterial
40 12689 24 4.827 0.82 42.0 33-
42 40 No 40
5 Eastern
Avenue
Sheila
Street
Commerce
Way
Other
Principal
Arterial
40 14859 13 4.827 0.82 41.8 33-
42 40 No 40
6 Ferguson
Drive
Gerhart
Avenue
East City
Limit
Major
Collector 30 4517 9 1.188 1.69 32.5 24-
33 30 Yes 252
7 Triggs Street Marianna
Avenue
McDonnell
Avenue
Major
Collector 25 6737 9 2.643 1.69 28.1 20-
29 25 No 25
(A): Street Classifications taken from the California Road Systems Map – FHA and Caltrans Reason for Reducing Speed from 85th% (Shown in Recommendations):
1 CVC 21400 (b) allows a 5 MPH Reduction in 85th% speed by 5 MPH for Rounding Down to Nearest Posted Limit. 2 CVC 627, 22358.5 and CAMUTCD 2B.13 allows the posted speed to be reduced by 5 MPH due to road conditions, land use. 3 CVC 627, 22358.5 posted speed may be set 5 MPH lower than 85th% based on a higher than expected collision rate, land use and roadway conditions.
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
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SECTION 4: CITY OF COMMERCE 2024 CITYWIDE SPEED LIMIT MAP AND AVERAGE DAILY TRAFFIC (ADT) MAP
The following pages consist of:
• City of Commerce 2024 Citywide Speed Limit Map
• City of Commerce 2024 Average Daily Traffic (ADT) Map.
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
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CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
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CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
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DRAFT
SECTION 5: ENGINEERING AND TRAFFIC SURVEY SUMMARY FORMS The following pages consist of the Engineering and Traffic Survey Grid and Summary Forms for each segment included in the Citywide Survey.
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 15 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 16 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 17 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 18 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 19 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 20 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 21 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 22 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 23 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 24 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 25 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 26 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 27 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 28 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 29 of 43
DRAFT
SECTION 6: AVERAGE DAILY TRAFFIC (ADT) COUNTS
The following pages consist of the ADT count sheets for all segments.
The Average Daily Traffic (ADT) data was obtained from counts taken by a private traffic counting firm in August 2024. These counts were taken while school was in session.
ADT counts were taken by NDS Services.
National Data & Surveying Services
8370 Wilshire Blvd. Ste, 205
Beverly Hills, CA 90211
Tel (323) 782-0090
Fax (323)375-1666
www.ndsdata.com
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 30 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 31 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 32 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 33 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 34 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 35 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 36 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 37 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 38 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 39 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 40 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 41 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 42 of 43
DRAFT
CITY OF COMMERCE 2024 ENGINEERING AND TRAFFIC SURVEY
Adopted by Commerce City Council Resolution No. XX on November X, 2024
CITY OF COMMERCE
Prepared By: Transtech Engineers, Inc. | Page 43 of 43
DRAFT