MFS Consulting Engineers & Surveyor, DPC (MFS) provide professional land surveying services for the Concept Development (CD) Phase for the U.S. Route 46 Over Hudson Branch, Structure No. 2108155, located in Independence Township, Warren County, New Jersey. This project involved preparing CD mapping and a control survey report to facilitate the improvement efforts for Structure No. 2108155 at milepost 16.55.
MFS employed photogrammetric methods to develop the topographic mapping for the project. Preflight targets were set and surveyed for location and elevation, and new low-level digital aerial imagery was acquired and processed using aero triangulation techniques. All visible planimetric features, including natural and man-made elements, were photogrammetrically compiled with a resolution of 1”=30’. Terrain breaklines and spot elevations were digitized and combined with ground-level planimetric data to create a digital terrain model (DTM) from which 1-foot contours were generated. Skilled technicians supervised by certified photogrammetrists ensured the mapping adhered to ASPRS Positional Accuracy Standards for Digital Geospatial Data. The final mapping was delivered in MicroStation V8i/SelectCAD format, with orthorectified aerial imagery provided in GeoTIFF or ECW format.
To complement the aerial mapping, MFS conducted supplemental field surveys 500 feet east and west of the structure along the U.S. Route 46 right-of-way. This process involved field editing the aerial base mapping, identifying mapped and non-mapped features, and collecting invert data for drainage structures.
Non-drainage structures were surveyed from the surface without entry. Additionally, MFS captured top-of-rail elevations for the abandoned railroad tracks extending approximately 100 feet from the bridge.
MFS also re-established the right-of-way (ROW) and roadway alignment for Route 46. This task required obtaining and reviewing ROW plans, roadway alignment documents, and “As Built” records from NJDOT. Field crews recovered evidence of ROW boundaries, and this evidence, combined with record documents, was analyzed to accurately re-establish the ROW and roadway alignment.
Survey control was a critical component of the project. MFS established primary and secondary survey control points using GNSS RTN and Leica SmartNet, adhering to the NJDOT Surveying Manual and Article 44. The horizontal control was tied to the New Jersey State Plane Coordinate System (NAD83), and vertical control was tied to NAVD88. Secondary control traverse baselines were established along the Route 46 corridor, with benchmarks set at staggered intervals. Differential leveling was performed to ensure accuracy. A Survey Control Report, signed and sealed by a licensed NJ surveyor, detailed computations, analysis, final coordinates, elevations, and diagrams for all semi-permanent control points.
Deliverables included orthorectified image files, topographic mapping, striping, breakline, 1-foot contour, Route 46 road alignment and ROW line files, and separate digital