Consultants Advise CJ on Response to Beltway Expansion Report

Cabin John residents have until Nov. 9 to submit comments in response to the the 19,000-page draft environmental impact statement (DEIS) on the state’s massive plan to expand I-495 and I-270 using variablepricing toll lanes.

Given the size of the DEIS and the complexity of all the potential impacts to our community, the Cabin John Citizens Association hired VHBMetroDC, a transportation, design, engineering and
consulting firm in mid-September to provide guidance.

The consulting contract came after a Sept. 10 emergency CJCA meeting, held via Zoom, during which the community authorized up to $2,000 for consultants to develop technical points that focus on the negative impacts to traffic on MacArthur Blvd., Seven Locks Rd. and Persimmon Tree Rd., both during construction and in the longer term.

The community also approved $1,000 to be given to help CJ’s Evergreen neighborhood on Cypress Grove Lane with their efforts to oppose any property takings on their street as well as to argue for noise barriers, storm water management and tree canopy replacement. The Carderock Springs Community Association also contracted with VHB for assistance with their comments. VHB is also providing pro bono consulting services to the Friends of Moses Hall & Cemetery to develop their written comments. Final comment letters from all of these groups will be posted as they become available.

The concerns raised in the DEIS are many. There is the overarching question of whether this project, estimated at $11 billion or more, is needed given the commuting changes brought about by the pandemic. Other serious concerns for Cabin John, including property takings, noise pollution, stormwater runoff, local road congestion, parkland loss, and negative impacts on our
cultural resources, such as the Moses Hall & Cemetery site and the C&O Canal. (See below for the various points that you could raise in your comment letter.)

Cabin John residents are urged to submit comments either via email to, or by letter to: Lisa Choplin, DBIA, I-495 & I-270 P3 Program Director, MDOT State Highway Administration I-495 & I-270 P3 Office, 707 North Calvert Street, Mail Stop P-601, Baltimore, MD 21202.

Whichever way you comment, it is most impactful if you share a copy of your comments with County Executive Marc Elrich and members of the County Council as well as our state delegates and congressional delegation. The CJCA would also be interested in a copy of your comment letter. Please send it to Susan Shipp at

Comment Letter: What to Say?

Here are points you could raise in a number of key areas:

The replacement of I-495 bridges over local roadways and the reconstruction of local roadway bridges over the highway could have substantial impact on our community’s commutes and quality of life. The Final EIS must detail potential roadway closures and needed modifications in these locations.

The current construction analysis fails to explain how construction materials would be stored and staged along I-495 between the C&C Canal and Seven Locks Rd. as well as the means and methods of constructing the new River Rd. (MD 190) off-ramp. A Supplement DEIS and Final EIS needs these disclosures and a Construction Management Plan. Cabin John would object to any staging/storage that causes disruption for our residents and/or affects sensitive areas like parkland and seeks a commitment to avoid such uses in the Final EIS.

The induced traffic created by the project could cause substantial long-term harm to our community. In the Traffic Technical Report, Figure 5-73 indicates that the Clara Barton Parkway and River Rd., would see greater than 10% increases in delays with the project. Despite this clear impact, this effect is not reported in the Draft EIS and is not proposed for mitigations. This failure must be addressed in a Supplemental DEIS with community impacts substantively resolved.

The analysis of arterials that do not intersect I-495 is limited and inconsistent, as reported in Figure 5-73. While MD 410 is analyzed for traffic impacts, other state highways like Wilson Rd. (MD 188) and Goldsboro Rd. (MD 614) are not evaluated.

MacArthur Blvd. and Seven Locks Rd., both critical non-state road commuter routes, do not receive any traffic impact analysis. This glaring omission is especially egregious as Appendix A of the Traffic Technical Report, states that the River Rd., Cabin John Parkway, and Clara Barton Parkway exit ramps will see
increases of up to 55% over existing volumes and up to 40% over volumes in the No-Build Alternative. No substantial modifications to the parkways are planned by SHA, Montgomery County, or the National Park Service. A Supplemental DEIS is needed to model the traffic impacts on Seven Locks and MacArthur and the Final EIS needs to include appropriate mitigation.

Future Clara Barton Parkway traffic would make use of MacArthur Blvd. at the Cabin John and Glen Echo exits, which are at unacceptable peak-hour operating conditions today. The constrained infrastructure in the area, including the one-lane Union Arch Bridge and the reversible lane management at Glen Echo, means limited ways to address the increased volumes. The Supplemental and Final EIS must include mitigations to minimize the impacts of commuter traffic spillover into our community.

The noise impacts as well as the visual impacts of the new MD 190 off-ramp are inadequately analyzed in the Draft EIS. More detailed noise analysis and a Visual Impact Assessment should be prepared and incorporated into a Supplemental DEIS for review and comment.

The MD 190 off-ramp would negatively affect sensitive wetlands and parkland, as shown in Appendix D. Section 4(f) considerations require the evaluation of approaches to avoid the use of such parkland. Because of the unacceptable visual and property impacts, the Final EIS should remove an eastbound flyover off-ramp onto MD 190 and replace it with an at-grade exit.

Past promises to provide noise barriers along I-495 in our vicinity have not been kept. While the Noise Analysis Technical Report (Appendix J) indicates it is feasible and reasonable to construct noise barriers along both sides of I-495 between Persimmon Tree Lane and Seven Locks Rd., the Final EIS, Record of Decision, and project implementation need to include a commitment by the SHA that noise barriers are constructed at no direct cost to residents.

The noise barrier design should include information about the location, height, grading, tree takings and its acoustical effectiveness so that it can be assessed by our community.

Even if the project does not move forward, we implore SHA and Montgomery County officials to develop a program and associated funding for “Type II” noise barriers to address the unconscionable onslaught of noise already subjected on our community.

The Moses Hall & Cemetery property is described in the DEIS as being “adversely affected” by all build alternatives. As currently designed, the limits of disturbance (LOD) would significantly impact the historic property, including portions of the Moses Hall foundation wall, a section of the access way from Seven Locks Rd, and grave locations. This is unacceptable and the final EIS must offer mitigation that protects this historic property.

We are concerned by the impacts to parks surrounding our community and insufficient efforts to avoid their use. Consistent with Section 4(f) of the Department of Transportation Act, use of Federal and local parkland should be avoided wherever possible. As indicated in the Environmental Resource Mapping (Appendix D), the construction of the project would affect meaningful portions of the C&O Canal. The off-ramp from I-495 to MD 190 would require substantial use of Cabin John Park.

The Draft Section 4(f) Evaluation (Appendix F) fails to document any efforts to avoid this use. Further avoidance measures must be pursued and described in the Final EIS.

The tree canopy and bucolic setting define Cabin John and substantial tree removal would alter the visual character of the community. Avoidance measures must be taken to reduce the number of trees affected by the project and should be documented in detail.

The stormwater analysis in the Draft EIS is inadequate to ensure that existing and future stormwater issues associated with the project are properly managed. According to the Natural Resources Technical Report, the Cabin John Creek watershed would see substantial impacts (Table 2.3-8). These impacts would result from additional impervious surfaces from the Alternatives (Table 2.9-60). The Final EIS must contain more detailed information regarding the Preferred Alternative approach to addressing stormwater in Cabin John and its environs.

CJCA President

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