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William Preston Lane Jr. Memorial (Bay) Bridge Automated Lane Closure System Project

The Bay Bridge automated lane closure system (ALCS) is a project constructed for opening and closing lanes including two-way traffic operations on the bridge. Since two-way operations were implemented, lane closures have been done manually. The ALCS will enhance the current manual system for motorists by allowing maintenance crews to remotely implement and discontinue two-way traffic on the Bay Bridge’s Eastern and Western Shores.

The ALCS includes overhead lane-use control signals, dynamic message signs, horizontal swing gates, and illuminated pavement markers. These enhancements are integrated into the existing bridge traffic control system.

Work on the project, such as conduit boring and installation, began in February 2020 on the Eastern Shore and January 2021 on the Western Shore. In Fall 2022, the MDTA began a phased implementation of the Bay Bridge ALCS to familiarize motorists to the new system. This transitional period includes some manual support of the system, with cones and barrels still present. Throughout the course of winter 2022/2023, additional phases of the system will be implemented on the Eastern and Western Shores.

The MDTA reminds those traveling on the Bay Bridge to adhere to overhead lane-use control signals for the safety of traffic operations and motorists.

Overhead Lane-Use Control Signals

  •  RED X - Lane is closed. Do not enter or travel in lane.
  • YELLOW X - Vacate lane. Move to a lane with DOWNWARD GREEN ARROW.
  • DOWNWARD GREEN ARROW - Lane is open.

*Failure to obey overhead lane-use control signals is subject to citation under Transportation Article, Section 21-204.1 – Lane direction control signals: “Where lane direction control signals are placed over the individual lanes of a highway, vehicular traffic may travel in any lane over which a green signal is shown, but may not enter or travel in any lane over which a red signal is shown." 

ALCS Lane Use Signals at the Bay Bridge

Dynamic message sign, overhead lane-use control signals and horizontal swing gates along westbound US 50/301 approaching the Bay Bridge.



(Westbound US 50/301) Driver’s Update

The Bay Bridge Automated Lane Closure System (ALCS) – designed to improve safety and the efficiency of bridge lane closures – is rolling out in phases, starting with westbound US 50/301 approaching the Bay Bridge from the Eastern Shore. Effective Dec. 20, 2022, the ALCS horizontal swing gates, illuminated pavement markers, full-color dynamic message signs (DMS) and overhead lane-use control signals now work in tandem to alert and guide motorists when lanes are opening and closing to accommodate two-way traffic operations on the westbound span. In November 2022, the new larger overhead lane-use control signals and DMS were activated.

  • Stay alert, obey posted speeds and keep moving through the open lanes.
  • Overhead lane-use control signals warn drivers of lane closures starting 1.5 miles before the westbound span.
  • During this transition period barrels still will be used.
  • Additional phases of the system will be implemented on the Eastern and Western Shores throughout the course of Winter 2022/2023.

For 24/7 Bay Bridge traffic information, call 1-877-BAYSPAN (1-877-229-7726) or visit For real-time updates on major incidents follow us on Twitter at Sign up for email/ text alerts at Find us at

Illuminated pavement markers.


Public Calendar

May 27

DriveEzMD Team - Orioles Game at Camden Yards

11 AM

Oriole Park at Camden Yards
333 W. Camden Street
Baltimore MD 21201

Hot Dog Race Shirt Day

11am – 1:05pm

Our DriveEzMD Team is in your community! Come talk with us about everything tolling – E-ZPass, Pay-By-Plate & Video Tolling. Pick up an E-ZPass On the Go and save up to 77% on your toll trips.

E-ZPass Pig With O's Bird

May 30

MDTA Board Meeting - May 30, 2024

9 AM


This public meeting is livestreamed and archived on the MDTA Board Meeting Homepage. The MDTA Board Meeting homepage also provides access to the meeting schedule, materials, agenda and minutes.

Jun 06

Capital Committee Meeting - June 6, 2024

9 AM


This public meeting is livestreamed and archived on the Capital Committee Meeting Homepage. The Capital Committee Meeting homepage also provides access to the virtual meeting, schedule, agenda, materials and minutes.