Glenhardie Road Closure Update - October 2025

Published on October 02, 2025

OCTOBER 22, 2025 UPDATE: From the Township Engineer - Township contractors PJ Reilly and CGS will begin work during week on October 27, 2025 to remediate sinkholes along Glenhardie Road. Sinkhole remediation will be occurring in several locations along the roadway and in the stream near the Glenhardie Road Bridge over Trout Creek. Please be advised that the contractors will be mobilizing some of their equipment and material to the site on Friday, October 24th.

Work is expected to last approximately 3 weeks and is weather dependent. Glenhardie Road will remain closed to all through traffic while the sinkhole remediation work is performed. Local residents living on Glenhardie Road between the PA Turnpike overpass bridge and Trout Creek will still be able to access their properties from Glenhardie Road coming south under the Turnpike overpass bridge during construction.

The Township will post a final update once the repairs have been completed and a date for reopening of Glenhardie Road is determined.

The Township thanks residents for their patience and understanding as the sinkhole remediation is performed on Glenhardie Road. If anyone has questions, please contact the Engineering Department at EngineeringDept@tredyffrin.org or Hilliary Mallory in the Engineering Department at 610-408-3626.

October 2, 2025: Tredyffrin Township continues work to address additional sinkholes that have surfaced along Glenhardie Road by the Glenhardie Road North Bridge over Trout Creek, near the intersection of Richards Road. Subsurface testing was conducted over the past several weeks, and was completed on Monday, September 29, 2025. The Township is working with our design team at Michael Baker Intl. (MBI) and contractors PJ Reilly and CGS to implement sinkhole remediation work and road repairs in the upcoming weeks.

Background:

Over the past 4 years, the Pennsylvania Turnpike has been working to widen and reconstruct the Turnpike along this section of Tredyffrin Township, between Route 422 and Route 252 (Valley Forge Road). The PA Turnpike substantially completed their roadway and bridge work in September 2024 and subsequently completed their grading/seeding/stabilization/fencing, as well as their conversion of their Temporary Erosion and Sediment Control Basin over to a Permanent Stormwater Management Basin, which is located along Glenhardie Road. This SW Basin work was completed in June 2025.

Tredyffrin Township started construction activities to remove and replace the old stone arch bridge over Trout Creek in September 2024. The Township’s project was substantially completed in late December 2024 with final grading/seeding/stabilization/painting/and landscaping completed in the spring of 2025. 

Earlier this year, the PA Turnpike Commission (PTC) experienced multiple sinkholes in their Stormwater Management Basin. This stormwater basin is located in close proximity to Glenhardie Road and the Glenhardie Road North Bridge over Trout Creek. They subsequently hired a contractor (CGS) to perform extensive drilling and grouting within the limits of the stormwater basin and surrounding areas along the Turnpike. Those operations occurred for several months, as new sinkholes surfaced over time in their newly constructed Aboveground Stormwater Basin. After several months of work, the PTC completed their sinkhole repair work, including placement of a liner within the bottom and sides of their Stormwater Basin, in June 2025.

On June 11, 2025, the Township experienced a sinkhole on Glenhardie Road near the bridge, and several weeks later another sinkhole opened nearby. Tredyffrin Township closed the roadway to all traffic due to public safety concerns. The Township worked with Michael Baker Intl. (MBI),  the Township’s bridge design consultant, and Hager-Richter Geoscience (HRGS), to conduct subsurface Ground Penetrating Radar (GPR) testing along Glenhardie Road and on both sides of the bridge over Trout Creek. Following the testing, MBI recommended sinkhole remediation measures, which included drilling and grouting along sections of Glenhardie Road on both sides of the bridge. PJ Reilly and CGS were hired to perform the drilling and grouting operations. CGS completed their work by the end of July 2025. Grouting included both pressure grouting and high mobility grouting, but was limited in spots due to the presence of numerous underground utilities. PJ Reilly performed the final surface repairs and milling and overlay of the asphalt pavement. PJ Reilly completed work in early August 2025. 

In August/September, additional sinkholes surfaced on the Richards Road side of the bridge and in Trout Creek. These sinkholes were located in areas outside of the previous drilling/grouting operations.  The Township and MBI monitored these sinkholes holes as additional testing were discussed and scheduled.  On both occasions, the Township notified MBI and they performed immediate onsite inspections, and recommended the Township maintain closure of the roadway to ensure the safety of the public.

Currently:

The Township is currently working with MBI to implement sinkhole remediation measures for these newly surfaced sinkholes. HRGS conducted various onsite testing using multiple testing methods (Ground Penetrating Radar (GPR), Seismic Refraction Tomography (SRT) and Electrical Resistivity Imaging (ERI)). Multiple methods were selected after consultation with MBI and HRGS representatives to ensure a thorough testing protocol is followed because of the presence of Trout Creek, underground utilities, the bridge, the presence of the new sinkholes and the varied depth to bedrock, etc. Testing was conducted on September 19, 2025 (GPR), September 25, 2025 (SRT), and September 29, 2025 (ERI). The Township and MBI are awaiting the final testing results from HRGS prior to moving ahead with future sinkhole remediation work. Sinkhole remediation work is anticipated to begin before the end of October 2025.

In the meantime, the Township and MBI continue to monitor the bridge and roadway.  Following completion of the sinkhole repairs, the Township will await recommendation from MBI prior to opening the roadway and bridge to traffic flow. The Township understands the inconvenience the road closure causes the community and traveling public but is doing everything it can to test and remediate these sinkholes to ensure the bridge and roadway are safe before reopening the roadway to traffic. The Township asks for the residents patience and understanding as this work moves forward.

Additional updates will be made once the repairs are scheduled/completed and once the roadway is ready for reopening. If there are any questions, please contact the Township Engineering Department at EngineeringDept@tredyffrin.org, or call Hilliary Mallory at 610-408-3626. We thank you for your continued patience during this time.