A map of proposed work to replace the Allens Lane Bridge at Allens Lane Station in Mt. Airy.

by Sue Ann Rybak

 PennDOT announced at the Mt. Airy-Nippon-Bryan-Cresheim Town Watch meeting on Feb. 1 that it is planning to replace the Allens Lane Bridge over SEPTA’s Chestnut Hill West Lane in the fall of 2018. The new structure is expected to be completed in Spring 2020.

The existing substructure was built in 1893, and the existing superstructure was built in 1908, according to Michael Holva, project manager for PennDOT, He added that the concrete bridge was replaced in 1961 with “routine maintenance completed over the years as needed.”

With Holva at the packed Town Watch meeting held in a member's home were Mehrdad Vahedi, transportation construction manager for PennDOT; Michael Duddy, principal at TranSystems; and Lee Wolfe, senior project manager for TranSystems.

Wolfe handed out copies of a PowerPoint presentation detailing the project and the proposed bridge, including discussing complications related to an existing gas line, which will be maintained during construction and maintenance of vehicular and pedestrian traffic.

The estimated construction cost is roughly $4 million. The new bridge will consist of reinforced concrete abutments, pre-stressed concrete box beams, a reinforced concrete deck and concrete bridge barriers. A geosynthetic reinforced slope will be installed parallel to the railroad tracks at the northwest corner of the bridge to stabilize the existing steep slope.

Holva said PennDOT anticipated that bids would be opened in Summer 2018.

“It typically takes about two to three months from bid opening to award the contract, execute the contract and the grant the contract notice to proceed and begin construction in the fall of 2018 (roughly late September),” he wrote in an email. “It is estimated that the total construction duration will be about 18 months, from fall 2018 to spring 2020.”

Residents voiced concerns about increased traffic while the road is temporarily closed and the noise level of construction.

Holva told attendees that the road will not close “immediately upon the start of construction in the fall of 2018.”

“There is work regarding the railroad catenary that must occur prior to beginning the bridge demolition,” he said. “It is anticipated the road would likely close beginning early 2019 and be closed for about a year.”

Several attendees expressed a desire for signage and suggested that “No Thruway” or “Local Traffic Only” signs be installed.

Holva told attendees the detour signage will include “Local Traffic Only” signs in advance of the road closure where the detour begins.

“Once the detour is put into place, traffic adjustments and the new traffic patterns are observed,” he said.  “PennDOT will look to make sure if any adjustments to the detour signage may be necessary. We plan to notify the school district well in advance of the closure, so that they have adequate time to plan for the closure.”

He added that most of the construction will occur during the day and trains will continue to operate.

“However, there are certain activities, such as placing or removing elements immediately over or adjacent to tracks that need to occur overnight when the trains are not running,” Holva said.  “PennDOT has a construction agreement with SEPTA for this project in which they will provide flagman for safety during construction. PennDOT's contractor will be required to follow SEPTA's safety regulations for work within their railroad right-of-way.”

If you have questions or concerns about this project, email Michael Holva at mholva@pa.gov.