Under an open-end surveying contract awarded to Larson Design Group (LDG) in 1996, we have performed numerous surveying projects for DCNR. LDG has been involved in numerous surveys for the replacement of bridges on roads in the State Forests.
These surveys were located across the entire eastern and northern sections of the state. The typical survey required establishing control that would allow the new structure to be located.
Our survey crews established horizontal and vertical control points on each side of the structure. The vertical benchmarks were generally spikes in the roots of trees, while the horizontal control points were steel pins driven flush and referenced to nearby trees or other features.
The existing structure and roadway were located. Topography around the bridge and at the proposed structure location was acquired.
One of the projects assigned was a survey for the construction of a snowmobile bridge to be constructed in the Poe Paddy area in Centre County.
This project required a survey to be performed across Penn’s Creek. The location of the eastern end of the proposed bridge was known within a few feet, but the western end was going to be dependent upon the environmental impact.
Our survey located significant trees in the possible project corridor and acquired topography on both sides of Penn’s Creek to allow design to be developed. A high water channel was located near the western end of the bridge and had to be taken into design consideration. A private cabin was also located near the western “tie out” on an existing snowmobile trail.
