The Pennsylvania Turnpike Commission (PA Turnpike) will construct a new stretch of mainline roadway to increase safety, reduce congestion, and allow for the free flow of traffic through Allegheny and Stonycreek Townships in Somerset County to the south of the Allegheny Tunnel.
Safety is paramount to the project. The selected alignment was chosen to achieve the following objectives for the Allegheny Mountain Realignment project:
Reduce the frequency and severity of accidents in the vicinity of the tunnel
Eliminate rerouting of vehicles carrying hazardous materials
Accommodate existing and future traffic volumes
Minimize environmental impacts
The new alignment will reduce congestion and increase access and mobility for the region.
The alternatives analysis phase of the project has been completed, and the preferred alternative was selected. The preliminary design phase began in March 2024 after the Bowman Consulting Group Team was selected in 2023. It is expected to take four years to complete the preliminary design. Final design is targeted to begin in 2028. Please complete the Join Mailing List to receive email updates about the project.
The gray cut alternative was identified as the preferred alternative because it best meets the project needs and balances environmental, engineering, operational, cost, and safety considerations. Numerous alignments were evaluated and presented to resource agencies, elected officials, and the public. The northern alignments were primarily dismissed due to the adverse impacts to the Indiana Bat population. The Tunnel Alternatives were primarily dismissed because they did not meet the project needs, due to cost, similar environmental impacts, safety at the approaches, and the movement of hazardous materials. The gray cut alternative was chosen as a result of environmental agency input during the study phase completed in 2021.
How will water quality be monitored and protected during and after construction?
Watersheds will be studied in more detail during preliminary engineering. The PA Turnpike will establish a water quality monitoring program that builds on past research and will monitor quality and flow to protect the local water supply and water resources. This monitoring program will include pre-construction, construction and post-construction water sampling and reporting. All work will be approached in compliance with the Federal Clean Water Act and state regulations to protect the local water supply and water resources. This will include collaboration with the local water authorities, such as Berlin Water, and property owners with wells and septic systems.
Will property owners be notified when field crews are planning to work on properties?
Yes. Property owners south of the existing tunnel received formal notification letters in July 2024 regarding upcoming fieldwork in the project corridor. Before entering private property, owners will be contacted and informed of the work plan. Contact information was gathered for each property owner. If you are a property owner within the project area and have not received correspondence, please contact the team at Allegheny Mountain Realignment - Team & Contact Info
How will property impacts be addressed?
Every effort will be made to minimize property impacts as part of the preliminary engineering phase of work. Access to properties will be maintained at all times during preliminary engineering, final design and construction.
When will the extent of environmental impacts be identified, especially as it relates to the footprint, acid mine drainage, wildlife, wetlands, vegetation and streams?
Once preliminary engineering is completed in 2028, environmental impacts on the new alternative will be shared.
How will you minimize environmental impacts throughout the project’s development?
The PA Turnpike will continue to comply with state and federal environmental regulations and is working together with state and federal agencies as the project progresses. A US Army Corps of Engineers permit will be required for the project and involves compliance with the many environmental and community resources studied in the environmental document. Coordination and compliance related to environmental and community resources will continue through preliminary design, final design, construction and post-construction. Innovative solutions to protect the environment are being studied, such as wildlife crossings and habitat improvements for plants and animals. Mitigation options will be explored in collaboration with state and federal agencies for any resource that can't be avoided.
How can I keep informed of the study’s progress?
The project website will be updated regularly. Please join the mailing list to receive project updates.
What phase is the project in?
The Allegheny Mountain Realignment Project is in the Preliminary Design Phase, which is expected to last approximately four years.
Why is the project needed?
Five needs are established for this project:
Transportation Demand: The current and future transportation demands on the tunnel and its approaches result in an unacceptable Level of Service (LOS) and traffic congestion.
Existing Geometric Constraints: Some geometric features of the tunnel and its approaches do not meet current highway design standards with respect to lane width, termination of truck climbing lane, horizontal curvature, and sight distance.
Accident Rates: The accident rate for the tunnel and its approaches is higher than the entire turnpike system and PennDOT statewide rates.
Tunnel Conditions: Both the eastbound and westbound tunnels are in need of major rehabilitation.
System Linkage and Continuity (continuous travel without required exiting): Certain hazardous materials are not permitted through the Allegheny Tunnel. Travel on the Turnpike is currently disrupted because of diversion of hazmat haulers to local roads.
What is the purpose of the project?
The purpose of the project is to:
Improve safety and decrease accidents for motorists traveling through this section of the Turnpike
Relieve traffic congestion and improve the level of service
Improve system linkage and continuity for hazardous material carriers, which are not permitted in the tunnel.
Where is the Allegheny Mountain Realignment Project?
The project is located approximately 13 miles east of Exit 110 (Somerset) and 23 miles west of Exit 146 (Bedford) on the Pennsylvania Turnpike. It spans the townships of Allegheny and Stonycreek in Somerset County. Please refer to the location map found on this website.
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Design & Construction Details
Find out about planned design & construction activities for this project.
