Washington Circle Traffic Operations Presentation by District Department of Transportation

October 21, 2015

Agenda

• “Before” and “After” comparison of Circle Operations with the reconfiguration of the Circle in May 2014

• Efforts to-date to improve traffic operations at the Circle

• Most recent traffic observations and recommended future measures

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BEFORE

RECONSTRUCTION

3

New Hampshire and Circle (South Side) – July 2011 4

New Hampshire and Circle (South Side) – Aug 2007

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23rd and Circle (South Side) Aug 2007

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Washington Circle - Today

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Comparison of “Before” and “After” Geometric/Traffic Control Features

Geometric/Traffic Control Feature

“Before” Condition “After” Condition

Number of Crosswalks 12 18 Number of Signalized Crosswalks

6 18

Number of Full Signals 4 8 Number of Partial Signals

2 0

Number of “Yield” Control Intersections

2 0

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PM Peak: Primary Flows

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“Before” Reconstruction Signal Timing (PM)

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Signal Timing (PM) From May 2015

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New Hampshire and Circle (South Side) – Aug 2014

14 14

23rd St and Circle (South Side) Aug 2014

15 15

23rd St and Circle (south) – June 2015

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23rd St and Circle (south) – June 2015

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Modifications To Date

• Signal timing has been optimized three times since May 2014 to improve traffic operations in and around the Circle

• 23rd Street (south side): signal phasing was modified and two exclusive eastbound right-turn lanes were provided to improve the traffic exiting the Circle

• Pennsylvania Ave. Intersections (east and west sides): modified signal phasing to implement “overlap” phases and provide more time for traffic exiting the circle

• Implemented multiple hold phases to meter traffic entering the circle so to keep traffic moving once they enter

• New Hampshire Avenue (south side): revised signal phasing and lane striping to make it easier for traffic to exit the circle at 23rd St. Southern-most eastbound lane at the intersection was converted to shared “through-right”

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Modifications To Date (cont.)

• Most intersections : adjusted splits to balance competing flows • Adjusted offsets to provide smoother flow around the circle • Increased the percent of cycle available to exit the circle on 23rd St (south

side) in the PM to over 50%. • Improved the offsets on 23rd St. south leaving the circle to minimize

disruptions it might create within the circle. • Improved progression along 24th St adjacent to the Circle • Improved outbound K St traffic flow leaving the Circle on the west side • Improved eastbound traffic on L St, north of the Circle Recent Changes as Part of Downtown Optimization • Increased cycle length by 10 seconds in the AM and PM to provide wider band and

more green time to critical circle movements. • Modified timings to improve the flow for EB K St. entering the circle in the AM.

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Parking Restrictions – Recently Implemented

Restrict meter parking on the east -side

PM Peak Recommendations

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Comparison of Level of Service and Delay (in seconds) AM Peak Hour

Intersection Name “Before” LOS/Delay – Prior to May 2014

“After” LOS/Delay – May 2014

Following Modifications (May 2014-Present) – “Current” LOS/Delay

CIRCLE/PENN. AVE (WEST) A/6.3 B/13.8 A/3.8

CIRCLE/K STREET OFF RAMP (WEST)

A/(N/A) B/11.8 B/8.6

CIRCLE/NEW HAMP. AVE (SOUTH)

A/3.4 E/69.6 E/65.2

CIRCLE/23RD STREET (SOUTH)

A/2.0 D/48.6 C/22.5

CIRCLE/PENN. AVE (EAST) B/16.9 A/6.3 A/9.5

CIRCLE/K STREET OFF RAMP (EAST)

A/(N/A) A/3.2 A/4.5

CIRCLE/NEW HAMP. AVE (NORTH)

A/0.3 E/68.9 D/50.5

CIRCLE/23RD STREET (NORTH)

A/0.2 B/11.3 B/13.9

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Comparison of Level of Service and Delay (in seconds) PM Peak Hour

Intersection Name “Before” LOS/Delay – Prior to May 2014

“After” LOS/Delay – May 2014

Following Modifications (May 2014-Present) – “Current” LOS/Delay

CIRCLE/PENN. AVE (WEST) B/12.3 B/17.7 C/27.8

CIRCLE/K STREET OFF RAMP (WEST)

A/(N/A) A/7.4 A/9.6

CIRCLE/NEW HAMP. AVE (SOUTH)

A/1.2 D/10.9 B/11.7

CIRCLE/23RD STREET (SOUTH)

B/11.5 F/201.4 C/29.7

CIRCLE/PENN. AVE (EAST) B/10.4 B/10.1 B/13.4

CIRCLE/K STREET OFF RAMP (EAST)

A/(N/A) C/25.0 C/25.6

CIRCLE/NEW HAMP. AVE (NORTH)

A/0.3 C/23.8 B/19.8

CIRCLE/23RD STREET (NORTH)

A/2.7 C/27.7 C/24.8

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Traffic Issues

Issue #1: Circle/23rd St (south-side) Placement of this crosswalk resulted in motorist’s confusion regd. where to stop along the

Circle

Issue #2: There is no stacking space between NH and 23rd – it restricts NB NH to get onto the

Circle

Issue #3: Circle/23rd St (south-side) Primary volume (1040/hr in PM peak – EB right turns) leaving

the Circle causing traffic congestion along the Circle, EB Penn (west side) and SB 23rd St

(north side)

Issue #4: Converting “yellow flash” operation to “green” signal (NB 23rd St) requires Circle traffic to stop unlike “before” condition – which

causes congestion along the Circle

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Alternatives

• Alt-1A: Retiming/Phasing (on the south-side), Marking/Parking/Signal Head Modifications

• Alt-1: Retiming/Phasing (on the south-side), Marking/Parking/Signal Head Modifications, Reduced “Green Cycle” on NB 23rd St

• Alt-2: Retiming/Phasing (on the south-side), Marking/Parking/Signal Head Modifications + Flash/Permissive Operation on NB 23rd St

• Alt-3: Crosswalk Relocation and Pedestrian Scramble + Flash/Permissive Operation on NB 23rd St

• Alt-4: Removal of the crosswalk from the south-side of the Circle at 23rd St + Flash/Permissive Operation on NB 23rd St

• Alt-5: Convert NB NH to one-way southbound + Flash/Permissive Operation on NB 23rd St

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Existing Condition

• All intersections currently performing at LOS “D” or better except for Circle/NH on the south side (LOS “E” in the AM peak)

• Traffic congestion issues at Circle/23rd on the south side has been reduced with the marking of double right-turn lanes and changes in parking regulation on SB 23rd St

• Short stacking space between New Hampshire and 23rd St (on the south side) continues to be an issue

• NB New Hampshire (on the south side) unable to utilize “green-time” to get onto the Circle

• EB right-turn traffic at the circle find it difficult to accomplish the turn due to heavy pedestrian activities on the south side

• NB 23rd St backs up due to curb-side parking on the east-side

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Retiming/Phasing (on the south-side) + Marking/Parking/Signal Head Modifications

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Pros • Provides more stacking space between NH and 23rd St (south side) and improved visibility to

signal heads; NB 23rd St queuing will be reduced with the parking restriction on the east-side of 23rd St

• Adjusting traffic progression between K St and 23rd St (south side) to prevent filling up short links

• South-side Ped at NH will be terminated during one of the phases to assist EBRT flow (south side)

Cons • While the NB NH flow will not change significantly, this alternative will create some

opportunities for NH traffic to get onto the Circle • Minor impact on the Circle due to the adjustment in progression

Provision to add future signal phasing

ALTERNATE – 1A

Alternative -1A: Signs/Marking Modifications

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ALTERNATE – 1

Retiming/Phasing (on the south-side) + Marking/Parking/Signal Head Modifications + Reduced Green on NB 23rd St

Pros • A short-phase added to existing condition to provide more opportunities for NB NH traffic to get

onto the Circle • Provides more stacking space between NH and 23rd St (south side) and improved visibility to signal

heads; NB 23rd St queuing will be reduced with the parking restriction on the east-side of 23rd St • Adjusting traffic progression between K St and 23rd St (south side) to prevent filling up short links • South-side Ped at NH will be terminated during one of the phases to assist EBRT flow (south side) Cons • NB 23rd St approach will be impacted with the reduction of “Green Arrow” phase; More queuing on

NB 23rd St approach • Potential for more traffic on NB NH approach • Minor impact on the Circle due to the adjustment in progression • Challenges with controller programming

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Pros • Provides more opportunities for NB NH traffic to get onto the Circle • Better level of service along the Circle with the reduction of NB 23rd St phase

Cons • NB 23rd has to rely on finding gaps in Circle Traffic (no signalized ROW). NB

23rd will be impacted mostly during the AM peak; Longer queuing on NB 23rd • Potential for more traffic on NB NH approach • Both crossings at 23rd St operating at the same time resulting in reduced

opportunity for pedestrians to travel between origin and destination points • Challenges with controller programming

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Retiming/Phasing (on the south-side) + Marking/Parking/Signal Head Modifications + Flash/Permissive Operation on NB 23rd St

ALTERNATE– 2

• Implement Alt-1A improvements by the end of 2015 • Observe new operations for a 60-day period • If NB NH problems continue to exist, consider

implementation of other feasible alternatives

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NEXT STEPS

Thank You