Mayor and Council

   For the meeting on:

  February 24, 2014
   Department:   Public Works
   Division:  Traffic and Transportation
   Responsible staff:  Emad Elshafei, Chief of Traffic and Transportation
  phone: (240) 314 - 8508

Safety Concerns at the Intersection of Great Falls Road/Maryland Avenue and the I-270/Falls Road Interchange

Receive staff presentation and discuss the intersection of Great Falls Road/Maryland Avenue and the I-270/Falls Road interchange

The Mayor and Council expressed a desire to discuss safety concerns at the intersection of Great Falls Road/Maryland Avenue and the interchange of I-270/Falls Road. In response to that request, staff has compiled information on accident and speeding data, as well as traffic configuration issues.

Intersection of Great Falls Road and Maryland Avenue

Concerns were raised about safety at the intersection of Great Falls Road/Maryland Avenue when two pedestrians were involved in a collision at the north leg of this intersection on the evening of January 31, 2013. This intersection, along with the crosswalks and a portion of each of all its four legs, is owned by the State Highway Administration (SHA). The traffic signal is operated and maintained by Montgomery County. City staff reviewed the crash report of the January 31, 2013 incident and examined the intersection. This review indicated that the crash was caused by the driver, who was making a left turn onto Great Falls Road and did not yield on green as required. The pedestrians had the right of way to cross Great Falls Road as the WALK signal was displayed.

Another crash took place at the same intersection in December 2013. This incident involved a vehicle traveling eastbound on Falls Road toward Town Center and a vehicle coming from Maryland Avenue turning left onto Potomac Valley Road. The crash was caused by the driver traveling on Maryland Avenue, who failed to yield the right of way to the eastbound traveling vehicle when turning onto Potomac Valley Road.

A review of State crash records for the three most recent available years (2010 - 2012) revealed eight crashes, including two in 2012 involving a vehicle turning left onto Great Falls Road. The crashes during this time frame are summarized below:

2010 2011 2012
Southbound Rear End: 2 Westbound Backing: 1 Eastbound Left Turn: 2
Eastbound Rear End: 1 Westbound Rear End: 1
Southbound Rear End: 1
Total in 2010: 3 crashes Total in 2011: 1 crash Total in 2012: 4 crashes

Potential Solutions

Since the Great Falls/Maryland intersection is owned by SHA, any changes to it would require SHA review and approval. Staff analyzed the intersection and identified a possible solution to improve safety at the intersection. This solution would entail making the left turn signal from Falls Road to Great Falls Road an exclusive left signal, meaning that drivers would not be able to turn left unless they have a green left arrow signal. In this scenario, pedestrians would be able to safely cross Great Falls Road while the WALK signal is displayed; at the same time, the left arrow would be red for drivers intending to turn left onto Great Falls Road. This measure would also prevent angle collisions between westbound traffic coming on Maryland Avenue from Town Center and eastbound left-turning traffic turning onto Great Falls Road. A down side of this measure is the potential reduction in the signal capacity and traffic efficiency and the possible creation of a longer queue for this left-turn movement.

Additionally, staff recommended to SHA that it consider the possible elimination of (or hatching) the second left turn lane coming from Falls Road to Great Falls Road as it creates confusion for drivers.

SHA Response

SHA has acknowledged the receipt of the City’s correspondence on 2/11/2013 regarding these issues and started reviewing possible improvements. SHA was in the process of upgrading the intersection during this time period, and a new streetlight was added. SHA also hatched one of the 2 exclusive left-turning lanes going from Falls Road to Great Falls Road, and placed delineators to force vehicles to use only the far left lane to make this left-turn movement. Finally, in January 2014, SHA added the long anticipated "Turning Vehicles Yield To Peds" sign for eastbound left-turning traffic as a short-term solution to protect pedestrians crossing the north leg of this intersection.

For a long-term solution, SHA was willing to consider the exclusive left-turn signal for eastbound traffic from Falls Road onto Great Falls Road at the subject intersection. SHA, however, would require two left-turn lanes to alleviate any queue for this left-turn movement. City staff reviewed this solution and expressed concern that adding a second left turn lane would force vehicles to merge quickly once they reach Great Falls Road as the merging distance is very short. Staff also had concerns that vehicles traveling close to the curb could create an unsafe situation for Julius West Middle School students who might be walking or present near the sidewalk on Great Falls Road.

City staff reviewed the traffic volume at this intersection and conducted a Synchro (traffic simulation model) analysis. The study revealed that the queue during the afternoon peak period is more critical than the morning period. However, a long queue is not expected and should not be a concern. Therefore, City staff recommended that only one left-turn lane be used with an exclusive left-turn signal.

SHA District 3 sent the City's recommendation to the SHA Office of Traffic and Safety (OOTS) for a design request. On February 10, 2014, SHA informed City staff that the design request was returned by OOTS as they would prefer to first determine if the “Turning Traffic Yield to Peds” sign is effective before considering any phasing change. If the sign does not work, it has been suggested that a Flashing Red operation could be considered. The flashing red signal would require drivers to stop before making a left turn movement onto Great Falls Road, but they could proceed after yielding to traffic traveling on Maryland Avenue from Town Center. This would eliminate the excessive speed for this left-turn movement and thus improve safety.

Interchange of I-270 and Falls Road

SHA also reviewed two concerns recently sent by City staff concerning the I-270/Falls Road interchange. SHA provided the following responses:

1) To alleviate the confusion for drivers in the center of the interchange of I-270/Falls Road, SHA staff is currently studying the City's request to install additional median treatment for the two left-turn movements at the interchange. SHA anticipates completion of this study within 30 days (mid-March 2014), and will provide their findings to the City upon completion.

2) With regard to the issue of pedestrian and vehicular safety at the top of the I-270 northbound exit ramp, for traffic going eastbound on Maryland Ave toward Rockville, SHA recently assigned a study of this ramp to a consultant to determine what could be done to address the issue of motorists not yielding to pedestrians within the crosswalk. SHA anticipates completion of the study in April 2014.

Speeding on Maryland Avenue

City staff examined speeding on Maryland Avenue to assess if a speeding issue exists. The posted speed limit on the section of Maryland Avenue between Great Falls Road and Argyle Street is 30 MPH for the eastbound direction and 35 MPH for the westbound direction. The 85th percentile speeds, (the speed that 85% of drivers travel at or below and which and is considered to be the national standard for assessing the speed of traffic) recorded at two different locations in November 2011 and April 2012 are summarized below:

Maryland Avenue, west of Monument Ave (November 2011)
Eastbound: 38.0 MPH (speed limit 30 MPH)
Westbound: 39.8 MPH (speed limit 35 MPH)

Maryland Avenue, east of Monument Ave (April 2012)
Eastbound: 40. 9 MPH (speed limit 30 MPH)
Westbound: 36.7 MPH (speed limit 35 MPH)

Based on the information above, the 85th percentile speed along the section of Maryland Avenue between Great Falls Road and Argyle Street is within the range between 1.7 and 10.9 MPH over the posted speed limits. Since Maryland Avenue is classified as an arterial road, with the purpose of carrying through traffic, there are limited speed reduction options. The road does not qualify for traffic calming measures based on the City Guidelines for Neighborhood Traffic Management. Even a primary residential street class I would not be considered for speed control unless the 85th percentile speed is at least 14 MPH over the speed limit.

To address speeding on Maryland Avenue, the City’s Traffic and Transportation Division posted a speed indicator sign for eastbound traffic on Maryland Avenue during the summer of 2013. New traffic counts were conducted in December 2013. The following results indicate that speed was reduced from 40.9 to 37.8 MPH for the eastbound direction:

Maryland Avenue, east of Monument Ave (December 2013)
Eastbound: 37.8 MPH (speed limit 30 MPH)
Westbound: 36.5 MPH (speed limit 35 MPH)

The Rockville City Police Department monitors Maryland Avenue as much as practical and possible. Speeding on this stretch of road has been a concern and an area of focus for the Police Department for some time. Since 1994, the Department has issued 8404 tickets and 8705 warnings on Maryland Avenue. In calendar year 2013, the Rockville City Police Department issued 171 tickets and 512 warnings. In addition, over the past three years, the Police Department has assigned staff to conduct specific traffic enforcement details in the area for targeted enforcement based upon citizen concerns. Information on those traffic enforcement details is provided below:

4 Traffic Details at:

  • Monument Park/550 Maryland Avenue
  • 150 Maryland Ave/100 Fleet Street
  • 200 Maryland Ave/104 W. Argyle Street
  • 500 Block of Maryland Avenue

Results of the traffic enforcement details:
92 Traffic Stops
10 Traffic Offenses/Traffic problems

No Traffic Details were scheduled but patrol checks of traffic offenses results in:
57 Traffic Stops
17 Traffic Offenses/Traffic Problems

2 Traffic Details at:

200 Maryland Ave at 104 W. Argyle Street
Maryland Ave @ Fleet Street

Results of the traffic enforcement details:
39 Traffic Stops
8 Traffic Offenses/Traffic Problems

School Zone on Maryland Avenue

Interest has been expressed in increased traffic enforcement on Maryland Avenue and the possible designation of a section of the road as a school zone - due to its proximity to Julius West Middle School – to allow for the installation of a speed camera. In response to this suggestion, staff reviewed the Maryland State Highway Administration Guidelines for Automated Speed Enforcement Systems in School Zones, dated January 2011. Based on that review, staff does not recommend the installation of a speed camera on Maryland Avenue. A joint memorandum from the Public Works Department and the Rockville City Police Department concerning this matter was provided to the Mayor and Council in December 2013 (Attachment A).

Mayor and Council History
This is the first time this item has been brought before the Mayor and Council.

Boards and Commissions Review
On February 26, 2013, the Traffic and Transportation Commission listened to the resident who was involved in the pedestrian crash of January 31, 2013 and discussed possible improvement options with staff. The Commission is interested in following up on SHA's suggestions to improve safety at this intersection.

Next Steps
Staff will continue to work with SHA staff and coordinate the implementation of some measures to improve safety at the locations referenced in this agenda item.

Attachment A - Speeding - MD Avenue.pdfAttachment A - Speeding - MD Avenue.pdf

Department Head:

Craig Simoneau, Director of Public Works
Approved on: 02/18/2014

City Manager:

Barbara B. Matthews, City Manager
Approved on: 02/20/2014