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201 Santa Monica Boulevard, Suite 500 Santa Monica, CA 90401 (310) 458-9916 Fax (310) 394-7663 www.fehrandpeers.com
MEMORANDUM TO: John Kaliski and Takako Tajima, Urban Studio FROM: Tom Gaul and Jill Liu DATE: October 6, 2008 SUBJECT: Ocean Park Boulevard Streetscape Improvement Project Ref: LA08-2286 City of Santa Monica
This memorandum summarizes Fehr & Peers’ review and assessment of the preliminary concepts for Ocean Park Boulevard Streetscape Improvement Project (Project). PROJECT ALTERNATIVES Two conceptual alternatives are currently proposed for the Ocean Park Boulevard corridor from Lincoln Boulevard to Neilson Way (September 9, 2008 version):
• Alternative A – Adapted from the OPB Task Force Consensus Plan
• Alternative B – Maximize Medians and Consequent Curb Space
Figure 1 and Figure 2 depict the alternatives. Both alternatives are aimed at enhancing safety for pedestrian, bicycle and vehicular movement in the study corridor and provide opportunities for street landscaping and beautification. Alternative A provides a moderate landscaped median with curb extensions at the intersections to reduce pedestrian crossing distance, while Alternative B maximizes the medians and maintains consequent curb space (without major curb extension). Following are the design features related to traffic operations in both alternatives:
• Modification of the lane assignment on the west leg and/or the east leg of Ocean Park Boulevard at Lincoln Boulevard
• Restriction of southbound left turn at the one-way stop-controlled North 7th Street and Ocean Park Boulevard intersection
• Addition of a new traffic signal at the 5th Street and Ocean Park Boulevard intersection, with consideration of possible pedestrian crosswalk crossing the east leg of Ocean Park Boulevard
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• Installation of landscaped median or islands by modification of traffic lane alignment and removing currently limited curb parking spaces on Ocean Park Boulevard between Lincoln Boulevard and Neilson Way
• Installation of physical barriers at Highlands Avenue and Beverly Avenue to enforce the left-turn restriction in addition to the currently posted “Right Turn Only” signs
In addition, Alternative B proposes new pedestrian crosswalks crossing Ocean Park Boulevard at Highland Avenue and at South 7th Street. Based on our review of existing and projected future traffic conditions, street parking, land use, and transit information in the study area, the following discussion provides our input on transportation impacts/implications of the preliminary streetscape project concepts, identifies potential issues and opportunities for safety enhancements, and suggests appropriate modifications. PROPOSED GEOMETRY CHANGE AT LINCOLN BOULEVARD AND OCEAN PARK BOULEVARD INTERSECTION Both Alternatives A and B propose modification to the lane assignment on the west leg of Ocean Park Boulevard at the Lincoln Boulevard intersection. This intersection currently provides one left-turn lane, one through lane and one right-turn lane on the eastbound approach, and one left-turn lane, one through lane and one shared through/right-turn lane on the remaining approaches. Alternative A proposes to modify the eastbound approach to provide one left-turn lane, one through lane and one shared through/right-turn lane. The westbound departure would retain the current lane assignment with a merging section from two to one lane by dropping the curb lane approximately 260 feet west of the intersection. However, Alternative B proposes to restripe the eastbound approach to provide one left-turn lane and one shared through/right-turn lane. To maximize the central median, Alternative B also proposes to modify the merging section of the westbound departure by dropping the inner lane approximately 100 feet west of Lincoln Boulevard. Per the City’s request, a subset of Alternative B was evaluated to create a merging section on Ocean Park Boulevard east of Lincoln Boulevard to allow only a through traffic lane westbound at this intersection. Adequacy of the Merge Distance The posted speed limit for Ocean Park Boulevard east of Lincoln Boulevard is 35 miles per hour (mph) and 30 mph west of Lincoln Boulevard. Application of California Manual on Uniform Traffic Control Devices (CA MUTCD) (Caltrans, September 26, 2006) indicates that the merging section from two to one lane for a 30 mph section should be designed to provide a recommended transition length of at least 135 feet if there are no geometry constraints. Alternative A would retain the current merge distance of 140 feet, which meets the standard.
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However, Alternative B would only have 100 feet, which would not meet the recommended practice for safe merge distance. Alternative B should be modified to include a safe merge section, which would require reducing the proposed median size. Furthermore, the lane drop by terminating the inner lane (the fast lane) is not a typical design, which may result in motorist confusion when first implemented. Intersection Level of Service and Queuing Conditions
The City’s TRAFFIX database provides year 2004 volume data and future 2014 projections for the Ocean Park Boulevard and Lincoln Boulevard intersection. Field observations were conducted to review existing 2008 operating conditions at this location. The City’s database was used to assess intersection level of service (LOS) and queuing conditions under future year 2014 baseline conditions and future with proposed alternative conditions. Table 1 summarizes 2014 intersection LOS and queuing results. Analysis of year 2004 volume data indicated that this intersection operated at LOS E (average vehicle delay of 60 seconds) in the AM peak hour and LOS F (average vehicle delay of 83 seconds) in the PM peak hour. On a typical weekday morning under existing conditions, the average queuing condition on the eastbound approach on Ocean Park Boulevard at Lincoln Boulevard was observed to be seven to eight vehicles at 8:00 AM. This average queue generally dispersed at the end of each signal cycle. From about 8:40 AM to 8:50 AM, the maximum queue length was observed for the eastbound through movement such the queue spilled back to halfway between South 7th Street and Highland Avenue. This maximum queue once interrupted the vehicles that intended to exit 7th Street. The eastbound left-turn pocket was fully utilized. It took two cycles to disperse this maximum queue. However, the eastbound right-turn pocket (starting from 7th Street to Lincoln Boulevard) was less utilized during the morning peak hour. In the PM peak hour, extensive queuing conditions were observed for all eastbound movements such that the queue spilled back to Highland Avenue. On average, two cycles were needed to clear out the eastbound queue. On the westbound approach, the average queue length was about four to five vehicles in the AM peak hour, with the maximum queue length extending beyond 10th Street. However, in the AM peak hour, an extensive westbound left-turn queue was observed such that it spilled back to halfway between 10th Street and 11th Street. Based on future year 2014 analysis shown in Table 1, Alternative A, with an additional eastbound through lane, would improve future LOS and queuing conditions from LOS F during peak both hours to LOS D during the AM peak hour and LOS E during the PM peak hour. However, with Alternative B, proposed removal of the eastbound right-turn pocket would result in an increase in average vehicle delay by approximately 20 seconds in both peak hours, and would extend the queue length by seven to eight vehicles on average. The maximum queue for the eastbound movement is expected to extend beyond Beverly Avenue. If a merging section was created for the westbound approach of Ocean Park Boulevard to allow only one through traffic lane passing Lincoln Boulevard, the effect of the merging would be noticeable in the PM peak hour such that an additional 10 seconds of average vehicle delay and extended queue length of almost 42 vehicles (beyond 11th Street) are expected.
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RESTRICTION OF THE LEFT TURN FROM NORTH 7TH STREET TO OCEAN PARK BOULEVARD In the project corridor, restrictions of the left turn from side streets to Ocean Park Boulevard are currently implemented at:
• South 6th Street (with “right-turn only” signage and physical barrier)
• South 7th Street (with “right-turn only” signage)
• Highland Avenue (with “right-turn only” signage)
• Beverly Avenue (with “right-turn only” signage)
Both Alternatives A and B propose installation of physical barriers at Highlands Avenue and Beverly Avenue to further enforce the left-turn restriction at these two locations. The intersection of North 7th Street and Ocean Park Boulevard does not have a restriction on the left-turn movement. Both Alternatives A and B propose restriction of the southbound left-turn movement at the one-way stop-controlled North 7th Street and Ocean Park Boulevard intersection. Restriction of the left turn from North 7th Street may result in additional neighborhood traffic circulation north of Ocean Park Boulevard or additional U-turn vehicles in the westbound left-turn pocket in front of Highland Avenue. Because this left-turn pocket is immediately east of the peak of Ocean Park Boulevard (with grade changes of approximately 8.32% on the south curb and up to approximately 9.32% on the north curb according to the City’s as-built plans), the visibility between oncoming eastbound traffic and a vehicle intending to make a U-turn is less than 250 feet. If southbound left turns were restricted at North 7th Street, consideration should be given to the prohibition of the westbound U-turn in the left-turn pocket in front of Highland Avenue. SIGNALIZATION OF 5TH STREET AND OPPORTUNITIES FOR A NEW PEDESTRIAN CROSSWALK Both Alternatives A and B propose a new traffic signal at the two-way stop-controlled 5th Street and Ocean Park Boulevard intersection. A new pedestrian crosswalk crossing is considered for the east leg of Ocean Park Boulevard. The reason for this new signal is to increase pedestrian connectivity for the surrounding communities and provide safe pedestrian crossing in this area. There are several issues to consider for the proposed signal and crosswalk at 5th Street. One is whether a crossing should be installed at all based on community needs, and second, whether a signal is the appropriate treatment for the crossing. Following is our review of existing intersection operations near this proposed crossing and our recommendations.
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Operating Conditions at 5th Street & Ocean Park Boulevard Per the City’s TRAFFIX model, future year 2014 peak hour volumes on Ocean Park Boulevard between 5th Street and 6th Street are estimated to range between 650 to 700 vehicles in each direction. With these estimated volumes on Ocean Park Boulevard, a minimum of 180 vehicles per hour exiting North or South 5th Streets would be needed to satisfy the CA MUTCD signal warrants. Based on the field observations, existing vehicle and pedestrian volumes exiting 5th Street are relatively low such that it may not meet the daily and the peak hour signal warrants if the traffic and land use density remain at similar levels. Pedestrian crossing of Ocean Park Boulevard is prohibited at 5th Street. There is a marked school crosswalk at the adjacent signalized intersection of 6th Street and Ocean Park Boulevard (approximately 220 feet east of 5th Street). There are signs posted on the southwest and southeast corners of the 5th Street and Ocean Park Boulevard intersection stating “No crossing, use crosswalks” pointing to the marked crosswalk at 6th Street. Also at the southwest corner, there is a speed limit sign posted for reduced speed of 25 mph for the school zone. Immediately west of the 5th Street and Ocean Park Boulevard intersection, there are westbound and eastbound ramps connecting Ocean Park Boulevard to the 4th Street overpass bridge. The City’s TRAFFIX database indicated that, in year 2004, approximately 155 vehicles were using the eastbound off-ramp at 5th Street during both the AM and PM peak hours. By year 2014, approximately 185 vehicles (three to four vehicles every minute) may use this eastbound off-ramp. Vehicles exiting the off-ramp are required to stop fully, then move forward and find a safe gap before they merge with Ocean Park Boulevard. Vehicles exiting the off-ramp were often observed to speed up when weaving into the travel lanes. Fehr & Peers also reviewed the City’s accident history for the project corridor from October 2004 to September 2007 (Attachment A). A total of 17 accidents were identified in the project corridor, and none of them involved pedestrians. One vehicle accident was filed at the intersection of 5th Street and Ocean Park Boulevard due to driving under the influence (DUI). Six accidents were filed at the 6th Street and Ocean Park Boulevard intersection, including one case involving bike motorist injury due to improper turning made by a car and other cases involving vehicle rear or side collisions due to unsafe speed, disobeying the traffic signal, following too close or improper turning. Four of the 17 cases (23%) involved unsafe speed issues. Therefore, the City’s recent accident data has not identified major traffic safety issues related to pedestrian violation of the posted signs, nor pedestrian-vehicle conflict at the unmarked crosswalks at other unsignalized intersections in the study area. Operating Conditions at 6th Street & Ocean Park Boulevard John Muir Elementary School and Santa Monica’s Alternative High School (SMASH) currently deploy two crossing guards to facilitate the pedestrian crossings on (1) the north and west legs of the 6th Street and Ocean Park Boulevard intersection, (2) the crossing at the north leg of 5th Street/Ocean Park Boulevard, and (3) the short crossing on the 4th Street westbound on-ramp that connects to the sidewalk on Ocean Park Boulevard. SMASH operates a bell schedule that starts at 8:20 AM and ends with multiple dismissals starting from 1:25 PM for kindergarteners, 2:35 PM for the 1st to 3rd graders and 2:50 PM for 4th and 5th graders. According to the City’s 2004 pedestrian count data at the 6th Street and Ocean Park Boulevard intersection, during the
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AM peak period, 98 pedestrians were crossing Ocean Park Boulevard, and approximately 113 pedestrians were crossing 6th Street. In the PM peak hour, approximately 15 pedestrians were crossing Ocean Park Boulevard, and 22 pedestrians were crossing 6th Street. This volume data is consistent with our recent field observations. Analysis of 2014 traffic projections indicates that this location would continue to operate at LOS B or better during both peak hours. Recommended Treatments for New Crosswalk at 5th Street The communities have asked the question if a marked crosswalk should be installed at 5th Street without appropriate treatments under both project alternatives. Three options are provided for further consideration: Option 1: Maintain Current Prohibition of Crossing. The existing school crosswalk at 6th Street is utilized by the school students and parents and is facilitated by the traffic signal and school crossing guards. With the observed four to five pedestrians per signal cycle during the morning peak hour (the busiest hour), the signalized crossing at 6th Street satisfies the school’s crossing demand. This signalized crosswalk is within reasonable walking distance (~220 feet) from 5th Street. Since the City’s recent accident data has not identified major traffic safety issues related to pedestrian violation of the posted signs nor pedestrian-vehicular conflict, the current direction for pedestrians to the marked crossing at 6th Street should still be considered as a option unless a citizen survey or walkability audits overwhelmingly suggest the need for a marked crosswalk with proactive treatment at this location. Option 2: Provision of HAWK Beacon Signal. Fehr & Peers examined several sources regarding the installation of crosswalks at uncontrolled/midblock intersections, including: (1) Improving Pedestrian Safety at Unsignalized Crossings (Transportation Research Board, 2006), and (2) A Technical Guide for Conducting Pedestrian Safety Assessments for California Cities (UC Berkeley, May 2008). If a marked crosswalk were installed at 5th Street, some of the estimated 100 pedestrians currently using 6th Street may choose to cross Ocean Park Boulevard via 5th Street. If more than 40 pedestrians per hour or 120 pedestrians per 4-hour period are expected to cross 5th Street, a High Intensity Activated Crosswalk (HAWK) Beacon Signal would be a candidate for pedestrian crossing treatment at this location, based on the review of the projected traffic conditions, pedestrian volume, speed limit, sight distance at 5th Street and motorists’ compliance. HAWKs are pedestrian-actuated signals that are a combination of a beacon flasher and a traffic control signal. When actuated, HAWK displays a yellow (warning) indication followed by a solid red light. During pedestrian clearance, the driver sees a flashing red “wig-wag” pattern until the clearance interval has ended and the signal goes dark. This application provides a pedestrian crossing without signal control for the side streets. Attachment B provides details on HAWK Beacon Signals. In addition, the presence of a median on Ocean Park Boulevard (as shown in Alternative B) and curb extension (bulb-out) at the northeast corner of the 5th Street and Ocean Park Boulevard intersection can also be considered to increase the visibility of the crossing and reduce the crossing distance. This would require pushing the curb out to match the same width as the parking lane, but should avoid interrupting the bike lane. A pedestrian crossing warning sign in
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advance of this intersection on Ocean Park Boulevard and a down ramp from 4th Street would also be required. If this option is implemented, SMASH may be required to deploy additional crossing guards to facilitate pedestrian movement at this marked crossing. Option 3: Install Conventional Traffic Signal and Marked Crosswalk. According to the above-mentioned traffic signal warrant criteria, 5th Street is not expected to meet the warrant based on the estimated traffic and pedestrian volumes. An exception is possible based on demonstrated pedestrian safety concerns or collision history, however, the City’s recent accident data has not identified major traffic safety issues related to pedestrian violation of the posted signs nor pedestrian-vehicular conflict. If the anticipated pedestrian crossing demand at 5th Street is expected to be over 75 pedestrians per hour, the proposed HAWK signal under Option 2 may be activated frequently such that it may result in a long vehicle queue on the stop-controlled down ramp from 4th Street because those vehicles (including the Big Blue Bus) cannot find a gap to merge with the vehicle flow on Ocean Park Boulevard. Then, installation of conventional traffic signal and marked crosswalk should be considered. This new signal should be coordinated with the adjacent signal at 6th Street. A separate signal phase should be provided for traffic exiting the down ramp from 4th Street. The above-mentioned central median (see Alternative B) and curb extension at the northeast corner of the 5th Street and Ocean Park Boulevard intersection could also be considered in this option. If this option is implemented, SMASH may be required to deploy additional crossing guards to facilitate pedestrian movement at this crossing. In summary, our analysis indicates that a crosswalk is not required at 5th Street. If the community and the City desire that a protected crossing should be provided at 5th Street, either Option 2 or Option 3 could be implemented, depending on the projected pedestrian and traffic volume data at this intersection (an uncontrolled crosswalk should not be provided). Peak hour and daily traffic and pedestrian counts should also be collected at the 5th Street and Ocean Park Boulevard intersection for further analysis before installation of any proactive crossing treatment. NEW PEDESTRIAN CROSSWALKS CROSSING HIGHLAND AVENUE AND SOUTH 7TH STREET As part of the Alternative B design features, new marked crosswalks are proposed at uncontrolled intersections at Highland Avenue and South 7th Street. Following is our review of the feasibility of these two crossings. Feasibility of Crossing at Highland Avenue Highland Avenue & Ocean Park Boulevard is a T-intersection, with a stop sign and “right-turn only” signage for Highland Avenue. On the north side of the intersection, an Overhead Flashing Beacon is installed to provide advance warning for the traffic signal at the 6th Street & Ocean Park Boulevard intersection. A Big Blue Bus stop is provided on the southwest corner of this intersection. This bus stop happens to be at the highest peaking point on Ocean Park Boulevard in terms of topography. The nearest marked crosswalks are at the 6th Street &
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Ocean Park intersection (approximately 430 feet to the west) and the Lincoln Boulevard & Ocean Park Boulevard intersection (approximately 740 feet to the east). Alternative B proposes to construct a landscaped median on Ocean Park Boulevard, a pedestrian crosswalk on the east leg of the intersection, and a physical island to prohibit the left-turn movement exiting Highland Avenue. Due to the vertical crest on Ocean Park Boulevard just west of the intersection, the visibility distance for motorists traveling eastbound to see pedestrians at the intersection is less than 250 feet (generally used for safe pedestrian planning purposes). No issue has been found with the visibility distance for motorists traveling westbound to see pedestrians at the intersection (~285 feet). Motorists in the westbound left-turn pocket on Ocean Park Boulevard as well as those making the northbound right turn exiting Highland Avenue would have to yield to pedestrians in this crossing. It is our understanding that this crossing is to provide access to the Big Blue Bus stop and increase pedestrian connectivity in this area. Given the topography changes and operating conditions at this intersection, an unsignalized marked crosswalk would not be recommended. We recommend that a proactive pedestrian treatment such as HAWK Beacon Signal be installed at this location. Along with the HAWK, installation of median (as shown in Alternative B) and installation of reduced speed sign and pedestrian crossing sign in advance of this location are also recommended. In addition, Fehr & Peers reviewed the possibility of moving the crosswalk to cross Ocean Park Boulevard on the west leg of the intersection. This would bring the pedestrian crossing closer to the bus stop and eliminate the conflict with the westbound left-turning and northbound right-turning vehicles. The proposed wide median could be designed to extend beyond the crosswalk to provide an enclosed pedestrian refuge. A six-foot wide median is the minimum width for provision of a pedestrian refuge. However, a solid median nose on Ocean Park Boulevard may affect fire truck or emergency vehicle access from Highland Avenue. To resolve this issue, the proposed physical island to prohibit left turns on Highland Avenue could be modified to provide painted markings on the pavement with a posted “Right-Turn Only” sign, unless the City has history that suggests low motorist compliance in this area. The pedestrian refuge area could also be provided as painted median such that the proposed physical barrier on Highland could be retained. This option would also require proactive pedestrian crosswalk treatment such as the HAWK Beacon Signal. Feasibility of Crossing at South 7th Street South 7th Street and Ocean Park Boulevard is a T-intersection with a stop sign, with posted signs for “Right-Turn Only.” The nearest crosswalk is at the Lincoln Boulevard and Ocean Park Boulevard intersection, approximately 330 feet to the east. The proposed new crosswalk at Highland Avenue would be approximately 350 feet to the west. Alternative B proposes to construct a pedestrian crosswalk crossing the west leg of the intersection and a landscaped median nose to provide a pedestrian refuge area. The nearest Big Blue Bus stop is the far side stop on the northwest corner of Lincoln Boulevard and Ocean Park Boulevard or the far side stop on the southeast corner of the Lincoln Boulevard and Ocean Park Boulevard intersection. As mentioned, the existing traffic queue for the eastbound
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movement at Ocean Park Boulevard and Lincoln Boulevard frequently extends beyond South 7th Street during the peak hours. Due to the significant grade drop from Highland Avenue to Lincoln Boulevard in this area, the eastbound travel speed of the motorists passing this location may be a concern. If the community has advocated strong desire for a pedestrian crossing at South 7th Street, we recommend that a speed survey and traffic and pedestrian count data be collected before installing a marked crosswalk. If the data and the survey suggest problems with speeding or motorist compliance issues in this area, a Stutter Flash design, an enhanced Overhead Flashing Beacon with rapid flashing LED lamps and powered by solar panel, could be considered along with the pedestrian refuge area. The beacons may be push-button activated or activated with pedestrian detection. OPPORTUNITIES FOR ROUNDABOUTS OR TRAFFIC CIRCLES As part of the project development, questions have been raised regarding the feasibility of roundabouts or traffic circles on Ocean Park Boulevard at 3rd Street , 5th Street, Highland Avenue, Neilson Way or elsewhere. Both roundabouts and traffic circles are used to slow intersection speeds to improve safety for pedestrians. Roundabouts A roundabout is a circular intersection with yield control for entering traffic, channelized at approaches, and travel speeds in the circulatory roadway of less than 20 mph. The roundabout dimension is the inscribed circle diameter, which includes the circulatory roadway. Depending on the size of the roundabout and the recommended speed operation, three types of roundabouts are generally considered, including:
• Single-lane roundabout (with inscribed diameter of 100 to 130 feet and recommended speed of 20 mph)
• Urban compact roundabout (with inscribed diameter of 80 to 100 feet and recommended speed of 15 mph)
• Mini roundabout (with inscribed diameter of 45 to 80 mph and suggested speed of 15 mph)
Attachment C provides more details for the geometry requirement for the above-mentioned types of roundabouts. Figures 3A and 3B demonstrate the geometry requirements for possible roundabout locations along Ocean Park Boulevard. Following are our review results:
• Neilson Way: This intersection can accommodate a compact roundabout. However, it requires conversion of the northbound and southbound approaches to single lane, which would result in extensive queuing conditions on Neilson Way during the peak hours due to the high traffic volumes on Neilson Way. Analysis of year 2014 conditions indicates this roundabout would operate at unacceptable LOS F during both peak hours (with
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average delay of 251 seconds in the AM peak hour and 130 seconds in the PM peak hour). Therefore, a roundabout would not be feasible at this location.
• Main Street: This intersection could accommodate a single-lane roundabout. However, it would also require conversion of the northbound and southbound approaches to single lanes, which would result in extensive queuing conditions on Main Street during the peak hours because of the relatively high traffic volumes on Main Street. Analysis of year 2014 conditions indicates this roundabout would operate at unacceptable LOS F in both the AM and PM peak hours (with average delay of 76 seconds in the AM peak hour and 68 seconds in the PM peak hour). Therefore, a roundabout is not feasible at this location.
• 2nd Street: This intersection would be a good candidate for a compact roundabout, with an inscribed diameter of 80 feet. The one-way operation on 2nd Street would simplify the traffic flow. The central island of the roundabout would provide landscape opportunities.
• 3rd Street and 5th Street: Both intersections have room for a compact roundabout. However, because of the small angle between Ocean Park Boulevard and the up- and down-ramps to the 4th Street Overpass, the splitter islands between two legs cannot be accommodated. Therefore, a roundabout is not recommended at this location.
• North 6th Street: A mini-roundabout has been reviewed for this location. However, because of the high pedestrian volumes to SMASH, it is recommended that the signalized crosswalk continue to be provided at this location. Therefore, a roundabout would not be recommended.
• Beverly Avenue, Highland Avenue, North 7th Street, South 7th Street: The possibility of installing a mini-roundabout was reviewed at these locations. Due to the proximity to the signal at 6th Street, the westbound queuing in the AM peak hour during the drop-off period often spills back to Beverly Avenue, which could interrupt the circulatory flow of a roundabout at Beverly Avenue. Similarly, the eastbound queuing on Ocean Park Boulevard at Lincoln Boulevard affects the operating conditions at South 7th Street. Because of the grade changes on Ocean Park Boulevard from Beverly Avenue to North 7th Street, vehicle speed at the mini-roundabouts would be difficult to control at Beverly Avenue, Highland Avenue and North 7th Street. Therefore, none of the intersections east of 6th Street and west of Lincoln Boulevard would be recommended for installation of roundabouts.
Traffic Circles Traffic circles are used to deflect and slow traffic, usually for traffic calming purposes. In the project corridor, traffic circles could be placed at some of the unsignalized intersections. However, the effectiveness of traffic circles in slowing traffic would be reduced with a wide street (generally 60 feet) such as Ocean Park Boulevard, but could present landscape opportunities. Attachment C provides a template for traffic circles.
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A traffic circle is possible at the unsignalized location on 2nd Street. Based on the existing street width of 62 feet from curb to curb on Ocean Park Boulevard, a traffic circle could be considered at this location. Because of the topography and grade changes on Ocean Park Boulevard, traffic circles would not be feasible at unsignalized 3rd Street, 5th Street, South 6th Street, Beverly Avenue, Highland Avenue and North 7th Street. The traffic circle at 2nd Street and South 7th Street may not work well either because of the queuing traffic spilling back from Lincoln Boulevard during the peak hour. OTHER ISSUES At the intersection of Ocean Park Boulevard and 3rd Street, vehicles making the southbound right turn from 3rd Street and vehicles coming from the down ramp are required to stop, and then yield to pedestrians and bicycles before they stop and merge with the westbound traffic on Ocean Park Boulevard. Because of the constrained geometry, the merging area at this location is narrow and difficult. To reduce the risks of vehicle conflict in this area, it is recommend a “Merge” sign be installed to warn the motorists traveling westbound on Ocean Park Boulevard in advance of 3rd Street that merging movements might be encountered at 3rd Street. A similar merging issue was observed at the 4th Street off-ramp at the 5th Street and Ocean Park Boulevard intersection. Even though this is a stop sign for the traffic exiting the 4th Street down-ramp, an advanced warning sign could be installed to alert the motorists traveling eastbound on Ocean Park Boulevard in advance of 5th Street to reduce potential vehicle conflict there. As part of the streetscape project Alternative B, several metered parking spaces on both the north and south curbs of Ocean Park Boulevard between Neilson Way and Main Street and on the south curb of Ocean Park Boulevard between Main Street and 2nd Street would be removed. The street parking in front of SMASH between 5th Street and 6th Street would also be removed as a result of the proposed median. We suggest that the City communicate with the adjacent retail owners or residents before removal of these spaces.
EB approach 1 LT, 1TH, 1RT 1 LT, 1TH, 1TH/RT 1 LT, 1TH/RT 1 LT, 1TH/RT
WB approach 1 LT, 1TH, 1TH/RT 1 LT, 1TH, 1TH/RT 1 LT, 1TH, 1TH/RT 1 LT, 1TH, 1RT
a.m. peak hour F, 81 seconds D, 49 seconds F, 106 seconds F, 107 seconds
p.m. peak hour F, 108 seconds E, 77 seconds F, 130 seconds F, 140 seconds
a.m. peak hour 28 cars/46 cars 15 cars/27 cars 37 cars/58 cars 37 cars/58 cars
p.m. peak hour 31 cars/49 cars 17cars/30 cars 38 cars/59 cars 38 cars/59 cars
a.m. peak hour 5 cars/11 cars 6 cars/12 cars 5 cars/10 cars 8 cars/15 cars
p.m. peak hour 9 cars/18 cars 12 cars/22 cars 9 cars/16 cars 26 cars/42 cars
Source: City of Santa Monica TRAFFIX database
Notes: LT: left-turn lane, TH: through lane, RT: right-turn lane, TH/RT: shared through and right-turn lane. EB: eastbound. WB: westbound
TABLE 1
INTERSECTION LOS AND QUEUING CONDITIONS AT OCEAN PARK & LINCOLN BOULEVARDS
Average and 95th percentile Queue Length
(number of cars per lane) for WB through
Year 2014 with
Subset of Alternative
B
2014 BaselineYear 2014 with
Alternative A
Year 2014 with
Alternative B
Peak Hour Intersection LOS and Delay
Proposed Geometry
Comparison of Alternatives
Average and 95th percentile Queue Length
(number of cars per lane) for EB through
ATTACHMENT A
ACCIDENT DATA
ATTACHMENT B
EXAMPLE OF HAWK BEACON SIGNAL
ATTACHMENT C
ROUNDABOUT AND TRAFFIC CIRCLE TEMPLATES
