Rocky Mountain Road over West Branch of Antietam Creek Culvert Replacement

County: Franklin
Municipality: Guilford Township
State Route: Route 233-023
Local Name: Rocky Mountain Road
Project Type: Culvert Replacement
MPMS Number: 90847
Proposed Construction Start:  March 2028
Proposed Construction End:  October 2028
Last Updated: September 2026

The project includes the replacement of an existing stone masonry and corrugated metal plate arch culvert, approach roadway pavement work and rehabilitation of Route 233-023 (Rocky Mountain Road) over West Branch of Antietam Creek in Guilford Township, Franklin County. The purpose of the project is to provide a sustainable crossing which addresses facility deficiencies.

Within the project area, Route 233 is a two-lane roadway located in a predominately wooded setting on rolling terrain and is classified as a Rural Major Collector. The land use surrounding the roadway is predominantly wooded areas within Michaux State Forest. The roadway within the project limits has a posted speed limit of 40 miles per hour and an average daily traffic volume of 1060 vehicles per day.

The existing structure was built in 1940 and reconstructed in 1961. The existing structure is 42’-0” in length and consists of a 25’-0” long stone masonry arch with a 9’-0” span at the downstream end and a 17’-0” long corrugated steel multi-plate pipe-arch with an 8’-9¾” span at the upstream end.

The proposed structure is an open bottom 10’-0” x 4’-10” aluminum box culvert with a length of 52’-0” between headwalls. The roadway across the drainage structure will consist of two 12’-0” lanes and 6’-0” shoulders and roadway work will include full-depth pavement reconstruction within the limits of work, which extend approximately 47 feet on the south approach and 43 feet on the north approach, measured from the culvert centerline.

Route 233 will be detoured during construction.

The project is currently in design, and construction is expected to occur during the 2028 construction season.

The purpose of the plans display is to introduce the project and solicit public input, questions, or concerns regarding the project.

Environmental

The project is in a predominately wooded setting on rolling terrain within Michaux State Forest. Wetlands and watercourse studies were conducted. No wetlands were determined to be present within the anticipated project limits of disturbance. West Branch Antietam Creek was identified to support the natural reproduction of trout.  In order to limit potential impacts to trout, the project will include a mitigation commitment preventing any in-stream work from occurring between the dates of October 1 and December 31 of any given year. A Pennsylvania Natural Diversity Index Environmental Review indicated the possible presence of endangered bat species. A Bat Assessment was conducted and it was concluded that bats are not using the existing culvert as roosting habitat.  No bicycle or pedestrian facilities exist within the project limits.  The State Forest land that will be impacted by the planned project on the south side of Route 233 was identified as a being purchased using Land and Water Conservation Fund [Section 6(f)] recreation grant funding.  No developed recreational facilities are currently present in the impacted area.  However, in order to minimize impacts to this Section 6(f) resource, the Pennsylvania Department of Transportation has coordinated with the Pennsylvania Department of Conservation and Natural Resources regarding culvert design.  In addition, it is anticipated that a Memorandum of Understanding will be developed, between both Departments, to provide for joint jurisdiction of the portion of the Section 6(f) property needed for construction and continued maintenance of the culvert.

Utilities

Utility coordination has been completed for the project. No utility relocations are required, and no known utility conflicts exist within the project limits. The project has received utility clearance, and excavation may proceed without anticipated utility-related restrictions.

Right-of-way

Permanent right-of-way acquisitions are anticipated to allow the construction of the project.

Maintenance and Protection of Traffic

Route 233 will be closed within the project limits for the duration of construction. An 11.4-mile detour is proposed, using Route 997, Route 30, and Route 233.

Schedule and Cost

Overall construction is anticipated to last approximately 4 to 6 months during the spring and summer of 2028 at an estimated cost of $350,000.