TC - Item 4C - Line of Sight Review at the Intersection of Mission Drive and Bartlett Avenue�i
TRANSTEch
TO: City of Rosemead, Department of Public Works
FROM: Traffic Engineering, Transtech Engineers, Inc.
DATE: February 17, 2022
SUBJECT: LINE OF SIG HTREVIEW ATTHE INTERSECTION OF MISSION DRIVE AND BARTLETT AVEN U E
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The City of Rosemead received a resident request to evaluate the line of sight visibility and existing
roadway conditions at the intersection of Bartlett Avenue (north of Mission Drive) and Mission Drive. In
response to this request and on behalf of the City, engineering staff completed a traffic review and
recommended appropriate curb markings to increase visibility for drivers turning from Bartlett Avenue
onto Mission Drive. The resident reported that vehicles park up to the curb returns on Mission Drive
making it difficult to see approaching and oncoming traffic on Mission Drive. The traffic review included
an analysis of the existing roadway conditions, a review of approximately 5 -years of available collision
data, and a line of sight analysis. Please refer to Figure 1 below for a vicinity map of the subject location.
Figure 1: Vicinity Map
CITY OF ROSEMEAD
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LINE OF SIGHT REVIEW AT THE INTERSECTION OF MISSION DRIVE AND BARTLETT AVENUE
EXISTING CONDITIONS
Mission Drive: Within the City of Rosemead, Mission Drive runs east and west and is considered a minor
arterial road by the California Road Functional Classification Map with a posted speed limit of 35 mph.
Mission Drive is approximately 64 feet wide with two lanes in each direction and a marked double yellow
centerline. Parking is allowed on the north and south side of Mission Drive except in areas marked by red
curb and on Tuesdays from SAM — 10AM to allow for street sweeping. This segment of Mission Drive
travels through Single Family Residential zoning, per the City of Rosemead Official Zoning Map.
Bartlett Avenue: Within the City of Rosemead, Bartlett Avenue runs north and south and is considered a
local road by the California Road Functional Classification Map with a prima facie speed limit of 25 mph.
Bartlett Avenue is approximately 36 feet wide with one lane of travel in each direction and no marked
center line. Parking is allowed on the east and west side of Bartlett Avenue except in areas marked by red
curb and on Tuesdays from SAM —10AM to allow for street sweeping. Bartlett Avenue is stop controlled
at Mission Drive, and the northern and southern segments are offset at Mission Drive. Figure 2 illustrates
existing roadway conditions. This segment of Bartlett Avenue travels through Single Family Residential
zoning, per the City of Rosemead Official Zoning Map.
Figure 2: Existing Conditions at Bartlett Avenue and Mission Drive
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STOPI
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STOPStop uo
PARK�ING No Parking due to
TU 5W Existing Red Curb
6-10. Street Sweeping
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CITY OF ROSEMEAD
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LINE OF SIGHT REVIEW AT THE INTERSECTION OF MISSION DRIVE AND BARTLETT AVENUE
PICTURE SUMMARY
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Eastbound along Mission Drive towards
North Segment of Bartlett Avenue
Looking North at North Segment of Bartlett
Avenue toward Mission Drive
Eastbound along Mission Drive towards
South Segment of Bartlett Avenue
R03& AD
v M
Westbound along Mission Drive towards
North Segment of Bartlett Avenue
J,
Looking South at North Segment of Bartlett
Avenue toward Mission Drive
F.
Westbound along Mission Drive towards
South Segment of Bartlett Avenue
Southbound at South Segment of Bartlett
Avenue toward Mission Drive
CITY OF ROSEMEAD
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LINE OF SIGHT REVIEW AT THE INTERSECTION OF MISSION DRIVE AND BARTLETT AVENUE
LINE OF SIGHT ANALYSIS
The driver of a vehicle approaching or departing from an
intersection or driveway should have an unobstructed
view of the intersection, including any traffic control
devices, and sufficient lengths along the intersecting
highway to permit the driver to anticipate and avoid
potential collisions (Maze and Plazak 2000). These
unobstructed views form trian ular areas known as
g Figure 3: Example of Stopping Sight Distance Triangle
sight triangles as seen in Figure 3. Any object within the
sight triangle that would obstruct the driver's view of an approaching vehicle should be removed or
modified or appropriate traffic control devices should be installed as per the Manual on Uniform Traffic
Control Devices. Obstructions within sight triangles could be buildings, vehicles, hedges, trees, bushes, tall
crops, walls, fences, or parked cars. A parked vehicle extends approximately 7 -feet from the curb, so it's
necessary to consider the width of a vehicle when determining the amount of red curb needed to obtain
a clear sight triangle.
Per A Policy on Geometric Design of Highways and Streets (AASHTO) Table 3-1, for a roadway with a
posted speed of 35 MPH the clear sight distance needed is 250 feet. Table 1 below summarizes the
Stopping Sight Distance based on design speeds and Figure 4 presents an example of a clear sight triangle
at an intersection.
Table 1: Stopping Sight Distance
Design
Speed
(MPH)
Brake reaction
distance
(ft)
Braking distance on
level
(ft)
sTRIEPeer
Calculated
(ft)
Design
(ft)
25
91.9
APPA TO DE MEAD Of
VIEW ONNTPUGTNIN
151.9
E EOOE Of eHWLDEP
—
\
�D
E!) EDGE OF PAVEMENT
196.7
® IY> STATE HIGHWAY
35
g Figure 3: Example of Stopping Sight Distance Triangle
sight triangles as seen in Figure 3. Any object within the
sight triangle that would obstruct the driver's view of an approaching vehicle should be removed or
modified or appropriate traffic control devices should be installed as per the Manual on Uniform Traffic
Control Devices. Obstructions within sight triangles could be buildings, vehicles, hedges, trees, bushes, tall
crops, walls, fences, or parked cars. A parked vehicle extends approximately 7 -feet from the curb, so it's
necessary to consider the width of a vehicle when determining the amount of red curb needed to obtain
a clear sight triangle.
Per A Policy on Geometric Design of Highways and Streets (AASHTO) Table 3-1, for a roadway with a
posted speed of 35 MPH the clear sight distance needed is 250 feet. Table 1 below summarizes the
Stopping Sight Distance based on design speeds and Figure 4 presents an example of a clear sight triangle
at an intersection.
Table 1: Stopping Sight Distance
Design
Speed
(MPH)
Brake reaction
distance
(ft)
Braking distance on
level
(ft)
Stopping Sight Distance
Calculated
(ft)
Design
(ft)
25
91.9
60.0
151.9
155
30
110.3
86.4
196.7
200
35
128.6
117.6
246.2
250
40
147.0
153.6
300.6
305
45
165.4
194.4
359.8
360
Note: Brake reaction distance predicated on a time of 2.5s; deceleration rate 11.2 ft/sect
Figure 4: Example of Stopping Sight Distance Triangle with Vehicles Parked Along Curb
Vehicle obstructing view
Slopping Si `...,_
Min 7distance for
vehicle clearance
Area to be clear of view
obstruction
CITY OF ROSEMEAD
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LINE OF SIGHT REVIEW AT THE INTERSECTION OF MISSION DRIVE AND BARTLETT AVENUE
Figure 5: Line of Sight Analysis for Vehicles Turning onto Mission Drive from SB Bartlett Avenue
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Legend x Existing Driveway
® Available curb space for parking (Approx. 178 feet)
Proposed Red Curb (35feet)
As shown in Figure 5 above, and based on the line of sight analysis, approximately 35 feet of red curb is
recommended to be installed on the north side of Mission Drive, just east of Bartlett Avenue. The red curb
will deter vehicles from parking up to the curb return and provide a clearer line of sight for vehicles exiting
Bartlett Avenue to see oncoming and approaching traffic on Mission Drive at this location. Mission Drive
is posted at 35 mph. The red curb installation equates to the removal of approximately 2 parking spaces.
There will still be approximately 178 feet of available curb space for vehicles to park along the north side
of Mission Drive between Bartlett Avenue and Dubonnet Avenue.
A Collision History Analysis was conducted for the subject location. Collision data was obtained from the
computerized collision records system maintained by the State of California called the Statewide
Integrated Traffic Records Systems (SWITRS). The collision analysis was conducted over approximately a
5.5 -year period between January 2016 through December 2021 (available data at the time of traffic
review). Based on the information provided, a summary breakdown of the number of collisions within the
studied segment are listed below and shown in Table 2.
2021-1 collision 2020-0 collisions 2019-0 collisions
2018 — 0 collisions 2017 — 0 collisions TOTAL: 1 COLLISION
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CITY OF ROSEMEAD
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LINE OF SIGHT REVIEW AT THE INTERSECTION OF MISSION DRIVE AND BARTLETT AVENUE
Table 2: Collision History Table for the Intersection of Mission Drive at Bartlett Avenue
Per the Collision History Analysis, there was a total of 1 collision reported within the 5 -year period for the
intersection at Mission Drive and Bartlett Avenue. This reported collision was a broadside collision that
resulted in property damage only. Please refer to Figure 6 provides a collision diagram of the collision that
occurred near the intersection of Bartlett Avenue and Mission Drive.
Figure 6: Collision Diagram for Mission Drive at Bartlett Avenue
CITY OF ROSEMEAD
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Severity
1- Fatal
2 -Severe Injury
Motor
Lighting
Collision
3 -Other Visible
Vehicle,
Collison Factor
Primary
IDN
Date
Primary
Secondary
Dist.
Time
DaY of the
(Day, Night,
type
Injury
Pedestrian,
and Detail
Collision
dlnj
Roatl
floatl
Week
Etc.)
C - Complaint of
Biryde
Descriptions
Factor
Pain
Involved
5 -Prop Dam
On PDO
WBENTTRAF
1
5/23/2021
MISSION DR
BARTLETT AVE
300'E
11:08
SUNDAY
DAYLIGHT
BROADSIDE
5
MOTOR
DRVRHITWB
R -O -W AUTO
0
VEHICLE
THRU DRVR
Per the Collision History Analysis, there was a total of 1 collision reported within the 5 -year period for the
intersection at Mission Drive and Bartlett Avenue. This reported collision was a broadside collision that
resulted in property damage only. Please refer to Figure 6 provides a collision diagram of the collision that
occurred near the intersection of Bartlett Avenue and Mission Drive.
Figure 6: Collision Diagram for Mission Drive at Bartlett Avenue
CITY OF ROSEMEAD
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LINE OF SIGHT REVIEW AT THE INTERSECTION OF MISSION DRIVE AND BARTLETT AVENUE
RECOMMENDATIONS
After a thorough review of existing field and traffic conditions and per the guidelines in the California
Manual on Uniform Traffic Control Devices (CAMUTCD), California Vehicle Code (CVC), and based on
engineering judgement, it was determined that the intersection of Bartlett Avenue (North of Mission
Drive) and Mission Drive would benefit from the installation of red curb along the northside of Mission
Drive, just east of Bartlett Avenue. The red curb will deter vehicles from parking up to the curb return and
provide a clearer line of sight for vehicles exiting Bartlett Avenue to see oncoming and approaching traffic
on Mission Drive at this location. Please refer to Figure 7 for a street view of the proposed
recommendations and Figure 8 for an aerial view of the proposed recommendations.
1. INSTALL RED CURB: Install approximately 35' of red curb on the north side of Mission Drive, east
of Bartlett Avenue. Please refer to Figure 7 & Figure 8.
Figure 7: Proposed Recommendations Diagram (Street View)
Figure 8: Proposed Recommendations Diagram (Aerial View)
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I
Legend O INSTALL APPROXIMATELY 35 FEET OF RED CURB ON THE NORTH SIDE OF MISSION DRIVE,
EAST OF BARTLETT AVENUE, AS SHOWN IN FIGURE 7 & FIGURE 8
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CITY OF ROSEMEAD
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1
Mission Dr
Figure 8: Proposed Recommendations Diagram (Aerial View)
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Legend O INSTALL APPROXIMATELY 35 FEET OF RED CURB ON THE NORTH SIDE OF MISSION DRIVE,
EAST OF BARTLETT AVENUE, AS SHOWN IN FIGURE 7 & FIGURE 8
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CITY OF ROSEMEAD
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