Intersection Control Report, SPUI - Railroad

© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Intersection Control Evaluation Report
This report conforms to the Caltrans Traffic Operations Policy Directive 13-02.
Intersection Control Evaluation (ICE) is a directive issued by the California Department of
Transportation (Caltrans) for all proposed highway intersection projects, whether new or for
improvement. ICE is performed during the early stages of a project, allocating time to study
which types of intersection control alternatives would work. Control types listed by ICE include
stop, signal, roundabout and lane configuration changes. Each is to get ample time for
consideration.
Railroad Canyon Road Interchange Improvement
Single Point Urban Interchange, SPUI
Cal Poly Pomona
Client
An interchange at Interstate 15 with Railroad Canyon Road in the
Location
City of Lake Elsinore, California. Coordinates: 33° 39’ 44.53” N,
117° 17’ 55.17” W
Number of Intersections 3
Signalized
Current Control(s)
Project
Alternative
Need for Control
The project site is located in a heavily traveled corridor within the city of Lake Elsinore. The
interchange exit with Railroad Canyon Road serves as the main arterial between the residences
of the city and major commuting routes along Interstate 15. There are significant truck routes
that pass the area as well. Therefore, it is necessary to assess the feasibility of various control
types for this project.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Figure 1 – Overview image of the intersections under consideration, numbered 1-3. The SPUI
alternative replaces the two circled ramp intersections.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Figure 2 – Intersection 1, Diamond Drive and Lakeshore Drive/Mission Trail
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Figure 3 – Intersection 2, Diamond Drive and Auto Center Drive/Casino Drive
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Figure 4 – Intersection 3, Railroad Canyon Road and Grape Street/Summerhill Drive
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Alternative Description
A Single Point Urban Interchange (SPUI) will replace the existing ramp intersections. A SPUI is a
type of interchange where ramps leading from the freeway diverge into separate hooks for left or
right movements. All left turns onto the local road is directed into the center. Likewise, the local road
also meets at the center to conduct its through and left movements. The central point is controlled by
only by one signal, hence the name SPUI. There is enough right-of way to accommodate the ramp
flares and central area. Traffic analysis show that the level of service is better improved than that of
the no build condition and ideal since there is just one signal. Geometrically, the interchange best
accommodates for large truck traffic if including retaining walls and a widened bridge. Costs for
such an alternative may be high.
Figure 5 – Image of a SPUI in with levels of service for projected 2040 PM volumes.
Figure 6 – A SPUI modeled in AutoCAD.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Step 1 – Configuration Assessment/Screening
Control Alternative Overview Table:
Intersection 1
Diamond Drive
and Lakeshore Drive/Mission Trail
Intersection 2
Diamond Drive
and Auto Center Drive/Casino
Drive
Intersection 3
Railroad Canyon Road
and Grape Street/Summerhill Drive
Stop
Control
Roundabout
Control
Signalized
Control
No
Yes
Yes
No
Yes
Yes
No
Yes
Yes
Intersection 1 – Diamond Drive and Lakeshore Drive/Mission Trail

Stop Control
A stop controlled intersection involves placing stop signs at the intersection, making vehicles that
pass through it have to stop and pass with caution. Based on the existing control at the
intersection there is no possibility a stop controlled intersection can handle the volume and
complexity of traffic going through. This alternative will not be considered in engineering
analysis.

Roundabout Control
Yield control involves slowing vehicle speed to a safe level while making them pay attention to
other vehicles in the intersection. One type yield control is the roundabout, a typically circular
road where vehicles can enter and exit from different roads. A roundabout can be implemented at
this intersection. There is enough right of way to design a traditional roundabout, possibly with
an increase of interior lanes and a road diet of the surrounding area. This alternative will be
considered further in engineering analysis.

Signalized Control
A signalized control uses traffic lights to coordinate movements in an intersection. The
current control is of this type. A change in timing and/or coordination with other signals is
likely needed. This alternative will be considered further in engineering analysis.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Intersection 2 – Diamond Drive and Auto Center Drive/Casino Drive

Stop Control
A stop controlled intersection involves placing stop signs at the intersection, making vehicles that
pass through it have to stop and pass with caution. Based on the existing control at the
intersection there is no possibility a stop controlled intersection can handle the volume and
complexity of traffic going through. This alternative will not be considered in engineering
analysis.

Roundabout Control
Yield control involves slowing vehicle speed to a safe level while making them pay attention to
other vehicles in the intersection. One type yield control is the roundabout, a typically circular
road where vehicles can enter and exit from different roads. A roundabout can be implemented at
this intersection. There is enough-right of way to design a traditional roundabout, possibly with
an increase of interior lanes and a road diet of the surrounding area. This alternative will be
considered further in engineering analysis.

Signalized Control
A signalized control uses traffic lights to coordinate movements in an intersection. The current
control is of this type. A change in timing and/or coordination with other signals is likely needed.
This alternative will be considered further in engineering analysis.
Intersection 3 – Railroad Canyon Road and Grape Street/Summerhill Drive

Stop Control
A stop controlled intersection involves placing stop signs at the intersection, making vehicles that
pass through it have to stop and pass with caution. Based on the existing control being signalized,
there is no possibility a stop controlled interchange can handle the volume and complexity of
traffic going through. This alternative will not be considered in engineering analysis.

Roundabout Control
Yield control involves slowing vehicle speed to a safe level while making them pay attention to
other vehicles in the intersection. One type yield control is the roundabout, a typically circular
road where vehicles can enter and exit from different roads. A roundabout can be implemented at
this intersection. There is enough right of way to design a traditional roundabout, possibly with
an increase of interior lanes and a road diet of the surrounding area. This alternative will be
considered further in engineering analysis.

Signalized Control
A signalized control uses traffic lights to coordinate movements in an intersection. The current
control is of this type. A change in timing and/or coordination with other signals is likely needed.
This alternative will be considered further in engineering analysis.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Step 2 – Engineering Analysis
Intersection 1 – Diamond Drive and Lakeshore Drive/Mission Trail

Roundabout Control
A traffic simulation was run using a traditional roundabout using yield control for entry points.
Lanes from all streets were reduced to two before entering the two lane roundabout. Existing and
predicted 2040 peak hour traffic volume was used. Results from this analysis concluded that the
roundabout will breakdown. Therefore, this alternative will not be considered.
Figure 7 – A roundabout simulation using projected 2040 volumes.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project

Signalized
A traffic simulation was run using a signalized control. Signals were re-implemented at this
intersection, but with a change of lane configurations of the surrounding streets and a change in
phasing/timing of the signal. Existing and predicted 2040 peak hour traffic volume was used.
Results from this analysis concluded that signalized control can handle the input. The Level of
Service at this intersection, along with other employed alternatives, during peak hours reaches a
D. This is an improvement from the existing conditions at a LOS of F.
Figure 8 – The existing signalized intersection with projected 2040 PM traffic volumes.

Other Considerations
Other intersection control methods, including left turn offsets, are likely to fail do to the need for
drastic lane configuration changes and purchase of considerable right of way.
It is recommended that the alternative selections be put into the study area network of
intersections to gauge its effect. However, since the standalone analysis already fails, then
inclusion into the network is not necessary.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Intersection 2 – Diamond Drive and Auto Center Drive/Casino Drive

Roundabout Control
A traffic simulation was run using a traditional roundabout using yield control for entry points.
Lanes from all streets were reduced to two before entering the two lane roundabout. Existing and
predicted 2040 peak hour traffic volume was used. Results from this analysis concluded that the
roundabout will breakdown. Therefore, this alternative will not be considered.
Figure 9 – A roundabout using projected 2040 volumes.

Signalized
A traffic simulation was run using a signalized control. Signals were re-implemented at this
intersection, but with a change of lane configurations of the surrounding streets and a change in
phasing/timing of the signal. Existing and predicted 2040 peak hour traffic volume was used.
Results from this analysis concluded that signalized control can handle the input. The Level of
Service at this intersection, along with other employed alternatives, during peak hours reaches a
D. This is an improvement from the existing conditions at a LOS of F.
Figure 10 – The existing signalized intersection with projected 2040 PM traffic volumes.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project

Other Considerations
Other intersection control methods, including left turn offsets, are likely to fail do to the need for
drastic lane configuration changes and purchase of considerable right of way.
It is recommended that the alternative selections be put into the study area network of
intersections to gauge its effect. However, since the standalone analysis already fails, then
inclusion into the network is not necessary.
Intersection 3 – Railroad Canyon Road and Grape Street/Summerhill Drive

Roundabout Control.
A traffic simulation was run using a traditional roundabout using yield control for entry points.
Lanes from all streets were reduced to two before entering the two lane roundabout. Existing and
predicted 2040 peak hour traffic volume was used. Results from this analysis concluded that the
roundabout will breakdown. Therefore, this alternative will not be considered.
Figure 11 – A roundabout using projected 2040 volumes.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project

Signalized
A traffic simulation was run using a signalized control. Signals were re-implemented at this
intersection, but with a change of lane configurations of the surrounding streets and a change in
phasing/timing of the signal. Existing and predicted 2040 peak hour traffic volume was used.
Results from this analysis concluded that signalized control can handle the input. The Level of
Service at this intersection, along with other employed alternatives, during peak hours reaches a
D. This is an improvement from the existing conditions at a LOS of F.
Figure 12 – The existing signalized intersection with projected 2040 PM traffic volumes.

Other Considerations
Other intersection control methods, including left turn offsets, are likely to fail do to the need for
drastic lane configuration changes and purchase of considerable right of way.
It is recommended that the alternative selections be put into the study area network of
intersections to gauge its effect. However, since the standalone analysis already fails, then
inclusion into the network is not necessary.
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© 2014 Cal Poly Pomona, Civil Engineering, Railroad Canyon Road Senior Project
Evaluation Summary
Stop control, roundabout control and non-traditional control at intersections 1, 2 and 3 are not likely
to work due to high volumes that are projected to exist within the life of the proposed project, year
2040. Therefore these alternatives will be rejected.
Based on an evaluation using predicted traffic conditions, signalized control for all intersections is
the likely candidate to be chosen for the SPUI and therefore recommended for the project.
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