I-495 & I-270 Managed Lanes Study

I-495 & I-270 Managed Lanes Study

I-495 & I-270 Managed Lanes Study


Joint Federal/State Application (JPA)

MDOT SHA has submitted a Joint Federal/State Application for the Alteration of Any Floodplain, Waterway, Tidal or Nontidal Wetland in Maryland, also known as the Joint Federal/State Permit Application (JPA) for the I-495 & I-270 Managed Lanes Study. The JPA is a permit application to the federal government (US Army Corps of Engineers) and Maryland State government (Maryland Department of the Environment) for authorization to impact regulated wetlands, wetland buffers, waterways, and the FEMA 100-year floodplain to construct the I-495 & I-270 Managed Lanes Study. The JPA application package includes a summary of efforts to avoid and minimize impacts to these resources, the resulting unavoidable impacts, and a compensatory mitigation package of wetland and stream creation/restoration sites to compensate for the impacts by improving existing wetlands and waterways or creating new resources.

JPA INFORMATION: The US Army Corps of Engineers (USACE) and Maryland Department of the Environment (MDE) have received and are evaluating the JPA as described below for Department of the Army authorization pursuant to Section 404 of the Clean Water Act (33 U.S.C. 1344) and Section 10 of the Rivers and Harbors Act (33 U.S.C . 403); and State authorization pursuant to Title 5, Subtitle 5 (Waterway Construction) and Title 5, Subtitle 9 (Nontidal Wetlands) of the Environment Article, Annotated Code of Maryland.


Maryland Department of Transportation
State Highway Administration
Attn: Ms. Lisa B. Choplin, DBIA
707 North Calvert Street
Mail Stop P-601
Baltimore, MD 21202

LEAD FEDERAL AGENCY: The Federal Highway Administration, as the lead federal agency, is responsible for all coordination pursuant to applicable federal authorities.

WATERWAY AND LOCATION OF THE PROPOSED WORK: The proposed project is located in the Middle-Potomac-Anacostia-Occoquan (02070010), Middle Potomac-Catoctin (02070008), and Patuxent (02060006) HUC-8 watersheds in Prince George’s and Montgomery counties, Maryland and Fairfax County, Virginia.

I-495 & I-270 MANAGED LANES NEPA STUDY PROJECT PURPOSE: The purpose of the I-495 & I-270 Managed Lanes NEPA Study is to develop a travel demand management solution(s) that addresses congestion, improves trip reliability on I-495 and I-270 within the project limits and enhances existing and planned multimodal mobility. The needs for the Study are:

    • Accommodate existing traffic and long-term traffic growth;
    • Enhance trip reliability;
    • Provide additional roadway travel choices;
    • Accommodate homeland security; and
    • Movement of goods and services.

Two additional goals for the Study were identified: the use of alternative funding approaches for financial viability and environmental responsibility.

PROJECT DESCRIPTION: The project limits include: I-495 from south of the George Washington Memorial Parkway in Virginia, including improvements to the American Legion Bridge over the Potomac River, to west of MD 5 in Maryland and along I-270 from I-495 to north of I-370, including the east and west I-270 spurs. There are six Build Alternatives under consideration for improvements within these limits. They are Alternatives 8, 9, 9M, 10, 13B, and 13C. Please see the table below for a summary of aquatic resource impacts by Build Alternative. Due to the preliminary nature of some of the JPA information, a second opportunity for public comment via a separate MDE public notice is anticipated if there are significant changes to the proposed nature, location or amount of proposed impacts. Any public comments received from a second public notice will be part of the administrative record and considered by both the USACE and MDE in their permit evaluation and decision.

On I-495, all Build Alternatives would consist of adding two Express Toll Lanes (ETLs) or High-Occupancy Vehicle Toll (HOT) managed lanes (MLs) in each direction, except for 9M which would only add one additional ML in each direction between the I-270 West Spur and the I-95 interchange. On I-270, Build Alternatives 8, 9, and 9M would have the same roadway footprint, but Build Alternative 8 would include one new ETL and one existing High-Occupancy Vehicle (HOV) lane in each direction, while Build Alternatives 9 and 9M would convert the HOV lane to a HOT lane and add a HOT lane in each direction. Build Alternative 10 would maintain the one existing HOV lane and add two ETLs in each direction. On I-270, Build Alternative 13B would convert the existing HOV lane in both directions to two reversible HOT lanes in the middle of the highway, separated from the general-purpose lanes by concrete barriers. Build Alternative 13C would be similar to 13B with two barrier-separated, reversible ETLs, except the existing HOV lane would be retained in both directions. Additional information about the Build Alternatives can be found in the DEIS.

USACE Anticipated Direct Effects On Regulated Aquatic Resources Of MLS Alternatives:

Proposed Alternative Totals Stream Impact Stream Impact Wetland Impact
Sq. Ft. Ac. Linear Feet Sq. Ft. Ac.
Alternative 8 1,751,484 40.21 135,192 702,478 16.18
Alternative 9 1,751,484 40.21 135,192 702,478 16.18
Alternative 9M 1,743,044 40.01 134,527 691,031 15.92
Alternative 10 1,762,105 40.45 136,245 710,212 16.35
Alternative 13B 1,750,538 40.19 135,104 701,290 16.15
Alternative 13C 1,757,140 40.34 135,902 708,562 16.32

MDE Anticipated Direct Effects On Regulated Aquatic Resources Of MLS Alternatives:

Proposed Alternative Totals Stream Impact Stream Impact Wetland Impact Wetland Buffer Impact Floodplain Impact
Sq. Ft. Ac. lf Sq. Ft. Ac. Sq. Ft. Ac. Sq. Ft. Ac.
Alternative 8 1,755,162 40.29 140,632 702,625 16.17 2,306,797 52.99 5,206,833 119.5
Alternative 9 1,755,162 40.29 140,632 702,625 16.17 2,306,797 52.99 5,206,833 119.5
Alternative 9M 1,752,947 40.24 141,116 691,178 15.91 2,285,645 52.50 5,075,288 116.5
Alternative 10 1,771,798 40.67 142,807 710,359 16.36 2,327,615 53.48 5,227,207 120.0
Alternative 13B 1,760,399 40.41 141,677 701,437 16.15 2,303,914 52.93 5,205,627 119.5
Alternative 13C 1,766,792 40.56 142,458 708,709 16.31 2,321,947 53.35 5,223,984 119.9

APPLICANT’S PROPOSED AVOIDANCE, MINIMIZATION, AND COMPENSATORY MITIGATION: Impacts to wetlands, their buffers, waterways, and the FEMA 100-year floodplain are being minimized to the greatest extent practicable at this stage of the project for all Build Alternatives. Avoidance and Minimization will continue throughout the design process.

Extensive design revisions were made to avoid and minimize direct impacts to natural resources including:

    • Elimination of the collector-distributor system on I-270;
    • Preliminary alignment shift designs;
    • Alterations to preliminary roadside ditch and grading designs;
    • Additions to preliminary retaining wall designs to minimize the roadway footprint;
    • Revisions to preliminary ramp designs, construction access areas, and preliminary stormwater management (SWM) facility locations; and
    • Relocations of preliminary managed lane access locations.

Wetland mitigation requirements in Maryland and Virginia were developed using USACE and MDE standard practices. For any chosen alternative, the mitigation requirement in Maryland is approximately 29.44 acres of wetland mitigation and 99,348 linear feet of stream mitigation. Several mitigation opportunities were explored including on-site mitigation for open channels, mitigation banking, in-lieu fee programs, and off-site permittee-responsible mitigation on public and private lands. Permittee-responsible mitigation sites were chosen for the Draft Compensatory Mitigation Plan based on their potential for functional uplift, construction feasibility, proximity to the study area, mitigation credits, and replacement of lost functions and values resulting from roadway improvements.

Thirteen wetland and stream mitigation sites are proposed in the three HUC-8 watersheds where the project is located. Six of the mitigation sites are located in the Middle Potomac-Anacostia-Occoquan watershed in Montgomery and Prince George’s counties, five sites are located in the Middle Potomac-Catoctin watershed in Montgomery and Frederick counties, and two sites are located in the Patuxent watershed in Prince George’s and Anne Arundel counties. Construction of the proposed wetland and stream mitigation sites would temporarily impact approximately 85 acres of wetland and approximately 90,000 linear feet of stream.

View the JPA Documents

The documents that comprise the JPA, and the USACE/MDE Public Notice follow:

View the JPA

Public Notice  
Part 1 Permit Application
Part 2

Impact Plates (a)

Impact Plates (b)

Part 3 MDE Impact Tables
Part 4 USACE Impact Tables
Part 5

Wetland Delineation Memo

Part 6: Wetland Delineation Memo Appendix A

Part 7: Wetland Delineation Memo Appendix B

Part 8: Wetland Delineation Memo Appendix C

Part 9: Wetland Delineation Memo Appendix D and E

Part 10A: Wetland Delineation Memo Appendix F (a)

Part 10B: Wetland Delineation Memo Appendix F (b)

Part 11A: Wetland Delineation Memo Appendix G (a)

Part 11B: Wetland Delineation Memo Appendix G (b)

Part 11C: Wetland Delineation Memo Appendix G (c)

Part 12 Avoidance Minimization and Impacts Report and Appendices
Part 13

Draft Compensatory Mitigation Plan

Part 14: Appendices A & B

Part 15: Appendices C & D

Part 16: Appendix E

Part 17: Appendices F, G and H

Part 18: Appendices I and J

Part 19: Appendix K

Part 20: Appendix L

Part 21: Appendix M