TO: Traffic Commission
SUBJECT: Speed Hump Installation Request Along Dunham Street between Duncan Avenue and McDonnell Avenue
MEETING DATE: August 11, 2021
RECOMMENDATION:
It is recommended that the Traffic Commission review the attached traffic study and approve the following recommendations:
1. Deny request for Speed Hump request along Dunham Street between Duncan Avenue and McDonnel Avenue.
2. Install “25” Speed Limit (R2-1) Regulatory signs with “25” pavement markings along Dunham Street for eastbound and westbound directions.
3. Repaint existing faded STOP Line and “STOP” pavement markings at the east leg of the Duncan Avenue and Dunham Street intersection and at the west leg of the McDonnell Avenue and Dunham Street intersection.
4. Install “CROSS TRAFFIC DOES NOT STOP” (W4-4P) Warning plaques below STOP signs at the north and south legs of the McBride Avenue and Dunham Street intersection.
CITY OF COMMERCE
AGENDA REPORT
Item No. 2
Traffic Commission Agenda Report – Meeting of 08/11/2021 Speed Hump Installation Request Dunham Street between Duncan Avenue and McDonnell Avenue
Figure 1. Proposed Recommendations Diagram
BACKGROUND:
The City of Commerce received a resident request regarding traffic control along Dunham Street between Duncan Avenue and McDonnell Avenue. The resident stated that speed humps were installed in the nearby streets, and vehicles are now diverting to Dunham Street and speeding down Dunham Street to avoid the speed humps in the adjacent streets. The resident has requested that speed humps be installed along Dunham Street to slow traffic. As part of the traffic review the following items were looked at: existing roadway conditions, 3 years of collision history, 24-hour traffic counts, and 24-hour speed survey at the segment of Dunham Street between Duncan Avenue and McDonnell Avenue. Please refer to the attached Traffic Study for the detailed analysis.
Within the City of Commerce, Dunham Street runs east/west and is considered a Local Road with a posted speed limit of 25mph. Dunham Street is approximately 35-feet wide with one lane in each direction and no marked centerline. The street has concrete cross gutters at McBride Avenue which acts as a natural speed deterrent.
As a part of the traffic study, the Average Daily Traffic (ADT) data was obtained from counts taken on Thursday, July 22, 2021, for Dunham St between Duncan Ave and McDonnell Ave which showed a total ADT volume of 306 vehicles per day along Dunham Street. A review of all collisions that occurred at the segment of Dunham Street from Duncan Avenue to McDonnell Avenue was conducted over a 3-year period between January 2018 through December 2020. According to the review of the collision history, there were a total of 5 accidents along the segment of Dunham Street between Duncan Avenue and McDonnell Avenue within the 3-year period. Of the 7 accidents, 2 collisions involved a parked car, 1 collision was due to unknown circumstances, 1 collision was due to a vehicle backing out into traffic, and 1 collision was due to automobile right of way issues. All collisions resulted in property damage only and no collision was due to speeding.
Traffic Commission Agenda Report – Meeting of 08/11/2021 Speed Hump Installation Request Dunham Street between Duncan Avenue and McDonnell Avenue
In order to assess the speed at which vehicles are traveling along Dunham Street from Duncan Avenue to McDonnell Avenue, a 24-hour speed survey was taken on Thursday, July 22, 2021, which determined that the 85th percentile speed of vehicles along Dunham Street is at 18 MPH which falls below the posted speed limit of 25 mph. There was no significant speeding observed, during the 24-hour period there was only 1 vehicle observed traveling over the speed limit, between the speeds of 25-29 MPH, during the hours of 5:00am to 6:00am. This data will be provided to the CSO and Sheriff Department which will allow for added enforcement as speeding occurs ANALYSIS:
COMMERCE SPEED HUMP POLICY:
The Speed Hump Policy states that the Public Works Department will determine which streets are eligible for speed humps based on site and roadway conditions, traffic conditions and proper engineering principles including, but not limited to, the following:
1. The street must be functionally classified as a residential, local, or collector street.
The street cannot be designated as an arterial or higher classification. (met, Dunham St is a residential street)
2. The street should be primarily residential in nature, but streets in commercially or industrially zoned areas can be eligible for speed humps, consistent with engineering analysis and safety concerns. (met)
3. The street should not be a truck, transit (bus) route, or emergency service route. (met, Dunham St is a local street and not a truck route or emergency service route, although it does serve as a local a transit route)
4. The street does not have more than one traffic lane in each direction. (met)
5. The street should have a minimum length of at least 500 feet, preferably 750 feet. (met, the segment of Dunham St between Duncan Ave and McDonnell Ave is approximately 585-feet)
6. The street must have a posted or prima facie speed limit not exceeding 30 milesper- hour. (met, the speed limit on Dunham St in 25 MPH)
7. The street must have a minimum ADT volume of 500 average daily vehicle trips and a maximum ADT volume of 4,000 vehicles per day and with additional assessment of potential impacts on streets with 4,000 to 10,000 average daily vehicle trips. (does not meet criteria, minimum ADT volume is lower)
8. The street must have adequate drainage and ADA access at street entrances and intersections. (met)
9. The street must have roadway pavement, curbs, gutters, adjoining parkways and sidewalks in good condition. (met)
10.The street cannot have any alignment, grade or sight-distance problems that would Traffic Commission Agenda Report – Meeting of 08/11/2021 Speed Hump Installation Request Dunham Street between Duncan Avenue and McDonnell Avenue
be affected or created by speed humps. (met)
11.Speed humps should not be spaced closer than 200 feet when two humps are installed on a single block and should not be spaced closer than 350 feet when three humps are installed on a single block. A speed hump should not be placed within 150 feet of any intersection. A speed hump shall never be installed within any intersection. (does not meet criteria, installing a speed hump right at the center of the block would place the speed hump at approximately 137-feet from the nearest intersections)
12.A speed hump should not be installed if it conflicts or interferes with:
• Drainage features including gutters, channels, drains, catch basins and manholes.
• Compliance with NPDES regulations for storm water run-off. • Fire hydrants, water valves, water meters, utility manholes or other utility facilities.
• Traffic control devices, including in-pavement signal detector devices. • Driveways, crosswalks, ramps and/or other ADA facilities/regulations. • Bicycle lanes.
• Horizontal or vertical curves in the street alignment or street profile
13.The City will attempt to not place a speed hump within 35 feet of any property edge where the resident of the subject property failed to endorse the petition or had specifically submitted a written objection to the speed hump. If needed, the City will adjust the spacing in between the speed humps accordingly for optimal.
14.The installation and final locations of Speed Humps should be based on the general guidelines in the Commerce Speed Hump Policy as well as Engineering Judgment and field conditions.
In addition to the items stated above, the Speed Hump Policy requires signatures of at least 75% of residents fronting the street where the Speed Humps are being requested demonstrating that they agree with the Speed Hump installation. The applicant submitted signatures of residents living along Dunham Street between Duncan Avenue and McDonnell Avenue. There are a total of 18 units fronting Dunham Street between Duncan Avenue and McDonnell Avenue. A minimum of 13 signatures is required for this segment.
The applicant obtained a total of 19 signatures, however, a few of which are from the same family and same address. Any signatures obtained from the same residence were excluded. The applicant obtained a total of 11 applicable signatures which does not meet the 75% requirement set by the Speed Hump Policy. This does not demonstrate that the majority of residents are in favor of having Speed Humps installed along Dunham Street between Duncan Avenue and McDonnell Avenue.
This segment of Dunham Street does not meet the criteria set by the Speed Hump Policy and the City may elect to not install speed humps. The block segments along Dunham Traffic Commission Agenda Report – Meeting of 08/11/2021 Speed Hump Installation Request Dunham Street between Duncan Avenue and McDonnell Avenue
Street between Duncan Avenue and McDonnell Avenue are approximately 275-feet in length and installing a speed hump right at the center of the block would place the speed hump at approximately 137-feet from the nearest intersections and based on the Speed Hump Policy the criteria states that “A speed hump should not be placed within 150-feet of any intersection”. Dunham Street also has an ADT volume of 306 vehicles per day which is slightly lower that the minimum recommended ADT volume of 500 vehicles per day.
Counts were conducted in July of 2021. It is important to note, there is less traffic overall on streets with residents working from home and children out from school. During these times it has been observed that traffic in most Cities has been reduced by 30 to 40%.
ALTERNATIVES:
1. Approve staff recommendation
2. Reject staff recommendation
3. Provide staff with further direction
FISCAL IMPACT:
No fiscal impact at this time. The preliminary construction cost and soft costs is estimated to be approximately $3,500.
Respectfully submitted,
Daniel Hernandez,
Director of Public Works
Recommended & prepared by:
Traffic Engineering
ATTACHMENTS:
1. Traffic Study