Nych Road Emergency Culvert Replacement Project
Project Owner:
Lackawannock Township
1742 Mercer-West Middlesex Road
Mercer, PA 16137
724.981.5055
Project Highlights:
- Obtained emergency GP-11 Permit for culvert replacement.
- Culvert designed to convey the 100-year design storm event, 281 CFS.
- Culvert designed to HS25 load rating.
- Full-service project (planning through construction contract closeout).
Nych Road Emergency Culvert Replacement Project
The existing culvert crossing on Nych Road consisted of an elliptical Corrugated Metal Pipe (CMP) and was in a failing condition with the invert completely deteriorated and catching debris inside of the culvert, and holes opening up in the roadway surface. Nych Road is a dead-end roadway and the residents had no other route of ingress/egress. IAG obtained an emergency GP-11 Permit for the immediate replacement of the culvert. The culvert was replaced with a new Aluminum Alloy Structural Plate Box Culvert, with a 6-inch submerged full invert to provide for a natural streambed. The new culvert was installed in the same alignment as the existing culvert.
The existing concrete headwalls were deteriorated and were demolished. The new culvert was provided with aluminum alloy head walls and wingwalls. Influent and effluent riprap protection was provided to prevent erosion/scour protection. Other site improvements consisted of roadside ditch improvements, installation of guiderail at the culvert crossing, and paved and non-paved site restoration. The culvert was designed for HS25 load rating, which meets the Pennsylvania Department of Transportation design load requirements, which is important if Liquid Fuels funding is used on a project.
The culvert was designed to pass the 100-year design storm peak flow. The drainage area tributary to the culvert was 256 acres with a peak flow of 281 CFS for the 100-year design storm. While the project was designed to have a temporary single lane vehicle bypass, the contractor received an approval from the Township to perform the work with a road closure. The contractor preassembled the culvert, excavated the existing culvert, installed the bedding, placed the new culvert in the alignment, backfilled the culvert and had the roadway open to traffic in less than 8 hours.