Slide One


I-495 & I-270 Managed Lanes Study

Purpose and Need

The purpose of the I-495 & I-270 Managed Lanes Study was to develop a travel demand management solution(s) that addresses congestion, improves trip reliability on I-495 and I-270 within the study limits and enhances existing and planned multimodal mobility and connectivity. The study addressed the following needs.

    • Accommodate Existing Traffic and Long-Term Traffic Growth. High travel demand from commuter, business, and recreational trips results in severe congestion from 7 to 10 hours per day on the study corridors, which is expected to deteriorate further by the planning horizon year of 2040. Additional capacity is needed to address existing and future travel demand and to allow travelers to use the facilities efficiently.
    • Enhance Trip Reliability. Congestion on I-495 and I-270 results in unpredictable travel times. Travelers and freight commodities place a high value on reaching their destinations in a timely and safe manner, and in recent years, the study corridors have become so unreliable that uncertain travel times are experienced daily. More dependable travel times are needed to ensure trip reliability.
    • Provide Additional Roadway Travel Choices. Travelers on I-495 and I-270 do not have enough options for efficient travel during extensive periods of congestion. Additional roadway management options are needed to improve travel choices, while retaining the general-purpose lanes.
    • Accommodate Homeland Security. The National Capital Region is considered the main hub of government, military, and community installations related to homeland security. These agencies and installations rely on quick, unobstructed roadway access during a homeland security threat. Additional capacity would assist in accommodating a population evacuation and improving emergency response access should an event related to homeland security occur.
    • Improve Movement of Goods and Services. I-495 and I-270 are major regional transportation networks that support the movement of passenger and freight travel within the National Capital Region. Existing congestion along both corridors increases the cost of doing business due to longer travel times and unreliable trips. The effects of this congestion on the movement of goods and services is a detriment to the health of the local, regional, and national economy. Efficient and reliable highway movement is necessary to accommodate passenger and freight travel, moving goods and services through the region.

Additional capacity and improvements to enhance reliability must be financially viable. MDOT’s traditional funding sources would be unable to effectively finance, construct, operate, and maintain improvements of this magnitude. Revenue sources that provide adequate funding, such as pricing options, are needed to achieve congestion relief and address existing high travel demand.

Given the highly constrained area surrounding the interstates in the study area, MDOT SHA recognized the need to plan and design this project in an environmentally responsible manner. The MDOT SHA strived to avoid and minimize community, natural, cultural, and other environmental impacts, and mitigate for these unavoidable impacts at an equal or greater value. The MDOT SHA worked with our federal, state, and local resource agency partners in a streamlined, collaborative, and cooperative way to meet all regulatory requirements to ensure the protection of significant environmental resources.  Any build alternatives would adequately offset unavoidable impacts while prioritizing and coordinating comprehensive mitigation measures near the study area which are meaningful to the environment and the community.