Gates Begin Operating Tuesday as Part of Bay Bridge ALCS Phased Implementation


Automated Lane Closure System/MDOT
Dynamic Messaging Sign / MDOT

On Tuesday, drivers crossing the Bay Bridge will experience the latest phase of an innovative project designed to improve safety and accelerate the process of opening and closing lanes on the bridge. Westbound drivers will see the use of new gates which are part of the Automated Lane Closure System (ALCS). This new system will eliminate the time consuming use of manually placing barrels to close off lanes.

Additional information from MDOT:

The Automated Lane Closure System uses horizontal swing gates, illuminated pavement markers, full-color dynamic message signs and overhead lane-use control signals to alert and guide motorists when lanes are opening and closing to accommodate two-way traffic operations on the westbound span.

The new gates and the entire ALCS helps protect Maryland Transportation Authority (MDTA) employees by replacing a manual process with automation, and improves safety for drivers as well by giving them more time to move into the correct lanes, allowing for safer lane changes and helping prevent secondary crashes during incidents. The ALCS also enhances incident response, enabling crews to switch between lane closure scenarios more rapidly during incidents. For a video simulation of the new system, visit

MDTA began to implement the system in November, when new overhead lane-use control signals and full-color dynamic message signs – a first in Maryland – became available on the Eastern Shore. Starting 1.5 miles before the westbound span, these devices give drivers more notice than ever before of bridge lane closures ahead.

This month, additional portions of the system are being rolled out on the Eastern Shore side of the bridge. To help drivers get used to this new system, the horizontal swing gates and illuminated pavement markers are being phased in.

In addition, during this transition period barrels still will be used – along with the new gates (see images below). Throughout the course of winter 2022/2023, the MDTA will complete phasing the system to include the Western Shore. For more information, visit