BALTIMORE, MD (June 17, 2022) – The Maryland Department of Transportation State Highway Administration (MDOT SHA) and Federal Highway Administration (FHWA) today published the Final Environmental Impact Statement (FEIS) and Final Section 4(f) Evaluation for the I-495 & I-270 Managed Lanes Study. The FEIS provides responses to comments received on the Draft Environmental Impact Statement (DEIS) and the Supplemental DEIS, as well as final traffic, engineering and environmental analyses related to the Preferred Alternative – Alternative 9 – Phase 1 South.
The FEIS also details the comprehensive mitigation plan for natural, cultural and socio-economic impacts. The FEIS and Final Section 4(f) Evaluation is available online at
The Preferred Alternative would
replace the more than 60-year-old American Legion Bridge, address existing traffic and long-term traffic growth, reduce congestion, enhance trip reliability, improve the movement of goods and services, support regional transit improvements, foster new opportunities for transit and increase carpool/vanpool/ridesharing opportunities to reduce reliance on single occupancy vehicles in the National Capital Region.
The FEIS also reflects successful efforts to
avoid all residential and business displacements with the Preferred Alternative, and reduce impact on parkland, right of way and other acreage within the study area. On Plummers Island, a research site for the Washington Biologists Field Club, the Preferred Alternative would reduce impacts by 90% to approximately 0.2 of an acre by strategically locating piers for the new American Legion Bridge.
Regarding traffic benefits, the FEIS traffic analysis concludes:
“The Preferred Alternative is projected to provide meaningful operational benefits to the system even though it includes no action or no improvements for a large portion of the study area to avoid and minimize environmental and property impacts. This alternative would significantly increase throughput across the (American Legion Bridge) and on the southern section of I-270 while reducing congestion. It would also increase speeds, improve reliability, and reduce travel times and delays along the majority of I-495, I-270, and the surrounding roadway network compared to the No-Build Alternative.”
Along with other new or upgraded pedestrian and bicycle improvements within the area of Phase 1 South, the Preferred Alternative would include a new shared-use path on the American Legion Bridge across the Potomac River along the east side. A direct connection of the shared-use path from the bridge to the Chesapeake and Ohio Canal towpath has been incorporated into the alternative. [FEIS, page 3-29]
On I-495, the Preferred Alternative would include two new High Occupancy Toll (HOT) managed lanes in each direction from south of the George Washington Memorial Parkway in Fairfax County, Va., to west of MD 187 (Old Georgetown Road) in Montgomery County, Md.
On I-270, the alternative would convert the existing high occupancy vehicle (HOV) lane in each direction to a HOT managed lane, and add one new HOT managed lane in each direction on I-270 from I-495 to north of I-370, and on the I-270 east and west spurs. No action or no improvements would be included at this time on I-495 east of the I-270 east spur to MD 5. [FEIS Chapter 3, Preferred Alternative]
As outlined in the FEIS, Alternative 9 – Phase 1 South is projected to do the following:
Reduce system-wide delay for the entire study area by 13% during the AM peak period and by 38% during the PM peak period compared to 2045 No Build conditions. [FEIS, page 4-10]
Improve travel speeds and provide the option for a free flow trip in the HOT managed lanes with an average speed of 60 mph, see Table 4-6 [FEIS, page 4-12], and provide benefits to the existing lanes by improving average speeds in the general purpose lanes. Detailed corridor travel speed results by peak hour and direction for the general purpose lanes and the managed lanes are provided in Table 4-7. [FEIS, page 4-13]
increased throughput by 2,000 vehicles per hour compared to the No Build Alternative, from an average of 15,700 vehicles per hour to an average of 17,700 vehicles across the American Legion Bridge and on I-270 north to I-370 while reducing congestion. [FEIS, page 4-15]
Reduce delay on surrounding local roadways, including a 4.8% reduction in daily delay on the arterials in Montgomery County, with some localized increases in arterial traffic near the managed lane access interchanges. [FEIS, page 4-16]
Some congestion would still be present during the PM peak period on I-270 northbound and the I-495 inner loop in the design year of 2045 due to downstream bottlenecks outside of the Preferred Alternative limits, but travelers on most corridors would experience significantly faster, more reliable trips.
New opportunities to support, expand transit
Beyond the travel benefits, the Preferred Alternative will create
new opportunities for regional transit bus service through a reliable trip in the HOT managed lanes, and would support carpooling by allowing HOV3+ vehicles and transit vehicles to travel in the HOT managed lanes toll free.
Other multimodal benefits identified in the FEIS include commitments to increase the number of bus bays at WMATA Shady Grove Metrorail Station and parking capacity at Westfield Montgomery Mall Transit Center. As part of the previously approved Phase Public-Private Partnership (P3) Agreement, the Phase Developer and MDOT SHA agreed to additional transit commitments when a Section P3 Agreement is approved by the Maryland Board of Public Works and financial close is achieved. These include an estimated $300 million for transit services in Montgomery County over the operating term of Phase 1 South.
After achieving financial close of the Section P3 Agreement for Phase 1 South, MDOT would fund not less than $60 million from the Development Rights Fee, provided by the developer, for design and permitting of high priority transit investments in Montgomery County, and would deliver the Metropolitan Grove Bus Operations and Maintenance Facility, including the necessary bus fleet.
Research will continue at Morningstar Tabernacle No. 88 Moses Hall and Cemetery
Regarding the historic Morningstar Tabernacle No. 88 Moses Hall and Cemetery in the Cabin John area, investigation to date indicates that the Preferred Alternative avoids impacts to the Morningstar Tabernacle No. 88 Moses Hall cemetery boundary and the known and suspected burial locations. MDOT SHA and FHWA will continue to work with the Maryland Historical Trust and consulting parties and will conduct additional archaeological surveys to support an ultimate determination of the effects.
MDOT SHA and FHWA remain committed to ongoing collaboration with stakeholders and pursuing community enhancements such as improved and new pedestrian connections between the cemetery and Gibson Grove Church, context sensitive design treatment of the proposed noise barrier adjacent to the cemetery, and improved drainage compatible with and beneficial to the property. MDOT SHA will continue working with the developer to ensure protection of the cemetery property.
The Preferred Alternative avoids the area within the cemetery’s historic boundary and includes a buffer zone for additional protection. After the historical research and archaeological surveys, MDOT and FHWA have determined there is a low potential for graves within the project’s limits of disturbance outside of the cemetery’s historic boundary. Regardless, MDOT SHA and FHWA have agreed that further investigations of this area outside of the cemetery’s historic boundary are appropriate.
Publication of the FEIS is the next major milestone in a four-year NEPA process that included 16 public workshops and seven public hearings with established public comment periods. Additionally, more than 200 stakeholder, community, elected official and business meetings were held to present study information and hear concerns and feedback.
In response to public and agency comments received over the course of the Managed Lanes Study, MDOT SHA and FHWA have modified analysis methodologies, conducted new analyses, studied new or modified existing alternatives, refined design to avoid and minimize environmental and community impacts, and identified meaningful mitigation to address unavoidable impacts.
The FEIS and Final Section 4(f) Evaluation are available online at
OpLanesMD.com/FEIS. Hard copies of the FEIS, as well as electronic copies of the FEIS technical reports and Final Section 4(f) Evaluation also are available for review at multiple library locations in Montgomery and Prince George’s counties, as well as one in Fairfax County, Va., and one in Washington, D.C. For a list of these locations, please visit
After an availability period for the FEIS, it is anticipated that FHWA will issue a Record of Decision (ROD) identifying the Selected Alternative, based on consideration of the range of reasonable alternatives, efforts to avoid and minimize impacts, and final mitigation measures designed to address potential environmental impacts. The ROD would conclude the NEPA process and document the commitments to be carried forth during final design and construction.
From intersection improvements to widening and new interchange construction, MDOT SHA is investing in projects to enhance the commute and daily travel for millions of Marylanders. MDOT SHA maintains more than 2,500 bridges and 17,000 miles of non-toll state roads – the interstate, US and state numbered routes in Maryland’s 23 counties.