16th Street Express
| Company type | Public transit service |
|---|---|
| Industry | Public transportation |
| Headquarters | Washington, D.C. , United States |
Area served | Washington, D.C., Maryland |
Key people | Washington Metropolitan Area Transit Authority |
| Products | Limited-stop Metrobus service |
| Parent | Washington Metropolitan Area Transit Authority |
The 16th Street Express, identified as Route D6X, is a limited-stop Metrobus service managed by the Washington Metropolitan Area Transit Authority. It links Silver Spring station on the Red Line with Federal Triangle located in Downtown Washington, D.C.. During peak hours, buses run every 5 to 12 minutes, with a 12-minute frequency during weekday midday periods and weekends from 7 AM to 9 PM. After 9 PM, service intervals extend to every 15 minutes. The duration of each trip generally ranges between 30 and 40 minutes. This route operates alongside route D60 to enhance transit options along the 16th Street corridor.
Background
Route D6X provides daily service connecting Silver Spring station and Federal Triangle, primarily following the 16th Street corridor. It functions as a limited-stop alternative to the local D60 route.
Since 2019, operations have been based out of the Montgomery division, having previously been managed by the Northern division. The fleet mainly consists of 2009 New Flyer DE40LFA buses, supplemented by other vehicles from Montgomery's inventory.
Route D6X Stops
<section begin=d6x-table/>
| Bus stop | Direction | Connections | ||
|---|---|---|---|---|
| Northwest Washington D.C. | ||||
| K Street NW / 13th Street NW (Franklin Square) |
Northbound station, Southbound terminal |
Template:Bus icon Metrobus: 3F, 3Y, 16E, 16Y, 80, D4, D6, S2, X2 Template:Bus icon DC Circulator: Georgetown–Union Station Woodley Park – Adams Morgan – McPherson Square Metro Template:Rint Washington Metro: Template:WMATA iconTemplate:WMATA iconTemplate:WMATA icon at McPherson Square | ||
| Franklin Square Bus Bay A |
Northbound | Template:Bus icon Metrobus: 3F, 3Y, 16E, 16Y, 52, 54, 59, 80, D4, D6, G8, S2, X2 Template:Bus icon DC Circulator: Woodley Park – Adams Morgan – McPherson Square Metro Georgetown–Union Station Template:Rint Washington Metro: Template:WMATA iconTemplate:WMATA iconTemplate:WMATA icon at McPherson Square | ||
| K Street NW / 15th Street NW | Northbound | Template:Bus icon Metrobus: 3Y, 16Y, 32, 33, 36, 80, D6, S2 Template:Bus icon DC Circulator: Georgetown–Union Station | ||
| K Street NW / 16th Street NW | Southbound | Template:Bus icon Metrobus: 3Y, 16Y, 32, 33, 36, 80, D6, S2 Template:Bus icon DC Circulator: Georgetown–Union Station | ||
| 16th Street NW / M Street NW | Bidirectional | Template:Bus icon Metrobus: S2 | ||
| 16th Street NW / P Street NW | Bidirectional | Template:Bus icon Metrobus: G2, S2 | ||
| 16th Street NW / U Street NW | Bidirectional | Template:Bus icon Metrobus: 90, 92 (Late night & early morning), 96, S2 | ||
| 16th Street NW / Euclid Street NW | Bidirectional | Template:Bus icon Metrobus: S2 | ||
| 16th Street NW / Irving Street NW (Columbia Heights station) |
Bidirectional | Template:Bus icon Metrobus: 52, 54, 59, D32, H2, H4, H8, S2, W45, W47 Template:Rint Washington Metro: Template:WMATA icon | ||
| 16th Street NW / Park Road NW | Bidirectional | Template:Bus icon Metrobus: H8, S2 | ||
| 16th Street NW / Spring Road NW | Northbound | Template:Bus icon Metrobus: S2 | ||
| 16th Street NW / #3636 | Southbound | Template:Bus icon Metrobus: S2 | ||
| 16th Street NW / Buchanan Street NW | Bidirectional | Template:Bus icon Metrobus: D33, S2, W45 | ||
| 16th Street NW / Colorado Avenue NW | Bidirectional | Template:Bus icon Metrobus: D33, S2 | ||
| 16th Street NW / Missouri Avenue NW | Bidirectional | Template:Bus icon Metrobus: D31, D33, D34, E4, S2, W45 | ||
| 16th Street NW / Somerset Place NW | Northbound | Template:Bus icon Metrobus: D31, S2 | ||
| 16th Street NW / Sheridan Street NW | Southbound | Template:Bus icon Metrobus: D31, S2 | ||
| 16th Street NW / Aspen Street NW | Bidirectional | Template:Bus icon Metrobus: D31, S2 | ||
| 16th Street NW / Alaska Avenue NW | Bidirectional | Template:Bus icon Metrobus: D31, S2 | ||
| 16th Street NW / Hemlock Street NW | Northbound | Template:Bus icon Metrobus: D31 | ||
| 16th Street NW / Holly Street NW | Southbound | Template:Bus icon Metrobus: D31 | ||
| 16th Street NW / Juniper Street NW | Bidirectional | Template:Bus icon Metrobus: D31 | ||
| 16th Street NW / Kalmia Road NW | Bidirectional | Template:Bus icon Metrobus: D31 | ||
| 16th Street NW / Leegate Road NW | Northbound | Template:Bus icon Metrobus: D31 | ||
| 16th Street NW / Myrtle Street NW | Southbound | Template:Bus icon Metrobus: D31 | ||
| 16th Street NW / Primrose Road NW | Bidirectional | Template:Bus icon Metrobus: D31 | ||
| 16th Street NW / Eastern Avenue (Washington, D.C.) | Northbound | Template:Bus icon Metrobus: D31, S2 | ||
| 16th Street NW / Portal Drive NW | Southbound | Template:Bus icon Metrobus: D31,S2 | ||
| Montgomery County, Maryland | ||||
| Silver Spring station Bus Bay 104 |
Southbound station, Northbound terminal |
Template:Bus icon Metrobus (Washington,D.C.): 70,79,F4,J1,J2,Q2,Q4,S2,Y2,Y7,Y8,Z2,Z6,Z7,Z8 Template:Bus icon Ride On: routes 1-22 and Flash BRT (Blue & Orange) Template:Bus icon MTA Maryland Bus:915 ,929 Template:RintWashington Metro : Template:WMATA icon Template:RintMARC Train : Brunswick Line Template:RintMaryland Transit Administration: Purple Line (Planned) | ||
<section end=d6x-table/>
History
Prior to the implementation of WMATA's Better Bus Redesign, the route now designated as D6X was formerly identified as Route S9. Initially, express transit service along the 16th Street corridor was offered by routes S3 and S5, which connected Silver Spring station to Franklin Square. These routes were phased out during the 1990s and replaced by routes S1, S2, and S4.
In 2008, WMATA partnered with the District Department of Transportation to conduct a comprehensive study aimed at enhancing service on the 16th Street corridor, which accommodates an average weekday ridership of approximately 16,000 passengers—ranking it as the third busiest Metrobus line. The study proposed introducing a new route S3 to shorten the existing routes S1, S2, and S4, alongside launching a limited-stop service designated as route S9.
S9
- Objective: Created to address lengthy travel durations and boost capacity during peak periods, route S9 operates similarly to the MetroExtra Georgia Avenue Limited Line (route 79), employing limited stops to accelerate transit compared to local services.
- Route Overview: The S9 traverses 16th Street between downtown Washington and the Maryland boundary, extending onto Alaska Avenue and Eastern Avenue. Unlike route S2, its southern endpoint is located near McPherson Square on Eye Street between 13th and 14th Streets (not continuing to Federal Triangle). The northern terminus is positioned close to Silver Spring station on Colesville Road just west of East-West Highway due to ongoing construction at the Paul S. Sarbanes Transit Center.
- Stops Served: The service includes only 16 stops in each travel direction.
- Service Frequency: During Phase 1, buses run every 10 minutes during weekday peak times; Phase 2 expanded this with additional peak frequency at 10-minute intervals plus service every 20 minutes during midday and late evening hours.
- Advantages: By limiting stops approximately every quarter mile, route S9 provides quicker travel times and greater capacity during peak periods for riders along the corridor.
S3
- Objective: Proposed to alleviate overcrowding concerns on the 16th Street Line by supplementing peak capacity in conjunction with route S9.
- Route Overview: The S3 would overlap with routes S2 and S4 from Federal Triangle through mid-corridor areas, with its northern terminus anticipated near Colorado Avenue.
- Stops Served: It would make stops identical to those on local routes S2 and S4.
- Service Frequency: Phase 2 planned included 10-minute intervals during peaks and 15-minute off-peak service; Phase 3 aimed for increased frequency with buses every 5 minutes at peak times and every 11 minutes off-peak.
- Advantages: This short-turn service was designed to reduce passenger congestion on existing lines by increasing bus frequency along 16th Street.
The concept for route S3 reemerged in corridor improvement discussions in 2013.
New Route S9
Launched on March 30, 2009, route S9 operates as a limited-stop express service running between Silver Spring station and McPherson Square via 16th Street NW. It serves sixteen stops during weekday peak periods, complementing routes S1, S2, and S4.
This introduction coincided with the deployment of hybrid New Flyer DE40LFA buses featuring a distinctive blue "express" paint scheme.
Following the June 2009 Red Line train collision, the S9 service was temporarily expanded to operate throughout weekdays but reverted back to peak-only operation by June 29 of that year.
In June 2012, WMATA incorporated the limited-stop express branding into its MetroExtra program; subsequently, route S9 was rebranded under this initiative in fall 2012.
With the opening of the Paul S. Sarbanes Transit Center in Silver Spring in 2015, route S9 was rerouted to serve Bus Bay 104 at this new facility.
WMATA’s FY2018 budget proposal introduced midday and Saturday service for route S9 at twenty-minute intervals and increased peak frequency to address overcrowding and improve travel times based on DDOT’s transit priority recommendations:
- Align limited-stop MetroExtra service more closely with passenger demand.
- Reduce congestion along the corridor by increasing faster trips.
- Streamline services for better customer comprehension.
Performance evaluations demonstrated strong ridership levels and cost recovery surpassing WMATA’s benchmarks:
| Performance Measure | Routes S2, S4 | Route S9 | WMATA Guideline | Result |
|---|---|---|---|---|
| Average Weekday Ridership | 13,258 | 3,913 | 432 | Pass |
| Cost Recovery Rate | 38.79% | 39.76% | 16.6% | Pass |
| Subsidy per Passenger | $1.85 | $1.77 | $4.81 | Pass |
| Riders per Trip | 36.9 | 37.0 | 10.7 | Pass |
| Riders per Revenue Mile | 4.8 | 4.8 | 1.3 | Pass |
Peak-hour trips frequently exceeded WMATA’s maximum load threshold of 120%, underscoring high demand pressures.
On June 25, 2017, midday and Saturday services were officially introduced alongside additional peak trips running between Missouri/Colorado avenues NW and Franklin Square.
In a 2019 proposal, WMATA suggested rerouting the S9 to continue directly along 16th Street (taking over from route S4) while extending evening hours and adding Sunday service at twenty-minute frequencies:
- Enhance speed and reduce travel time based on rider feedback.
- Strengthen connectivity between Downtown DC and Silver Spring.
- Mitigate traffic congestion through more frequent MetroExtra trips.
- Increase reliability and decrease bus bunching occurrences.
- Simplify routing for easier passenger understanding.
- Operate all trips end-to-end along the corridor.
This change would impact under one percent of riders using stops north of Alaska Avenue NW that would be discontinued but maintain nearby access via routes such as the S2.
Later in that year, WMATA proposed raising MetroExtra fares from $2.00 to $3.00 concurrent with extended operating hours for route S9.
Due to the COVID-19 pandemic, starting March 16, 2020, route S9 operated on a reduced Saturday schedule before full suspension on March 18 under modified Sunday schedules.
Service resumed on August 23, 2020 with a permanent reroute along alternate streets following Black Lives Matter Plaza's designation; evening hours were extended until 11:00 PM Monday through Saturday while Sunday service was added operating from 7:00 AM to 7:00 PM every twenty minutes.
On September 5, 2021, service frequency improved to twelve-minute intervals daily.
As part of WMATA’s Better Bus Redesign effective June 29, 2025, route S9 will be renamed D6X with an extension reaching Federal Triangle; simultaneously, route S2 will be shortened to terminate at McPherson Square and renamed D60.