2022 and 2024 Lidar Digital Elevation Models Acquired via Small Unoccupied Aerial System Surveys of Maurice River, NJ Beneficial Use of Dredged Material Placement Site 1

To assess the pre- and post-placement surface elevations of the area of the Maurice River marsh and mudflat adjacent to the Heislerville Dike nourished in October 2023 to January 2024 , unmanned aerial systems (UAS) lidar surveys were performed. The projected coordinate system for the datasets is NAD 1983 StatePlane New Jersey FIPS 2900 (US Feet) and the vertical coordinate system in the datasets is the North American Vertical Datum of 1988 (US survey feet), which is ~ 0.46 ft (0.14 m) below local mean sea level. The following data summary is from the authors' manuscript submitted to ASCE's Journal of Waterway, Port, Coastal, and Ocean Engineering: "The low-tide (i.e., mudflat was exposed) pre-placement lidar survey was performed on May 17, 2022 with a FreeFly Alta X outfitted with a Phoenix Lidar Systems MiniRanger Lite with a RIEGL miniVUX-3UAV sensor. The low-tide post-placement lidar survey was performed on March 15, 2024 (3-months post-placement) with a UAS mounted GeoCue True View 640 carried on an Inspired Flight 1200. The True View 640 contains a Riegel miniVUX-3UAV sensor and Applanix APX-20 GNSS with dual Inertial Measurement Units). The 2022 lidar was processed in Phoenix Lidar System’s LiDARMill software while the 2024 lidar was processed in GeoCue’s LP360 software. Classification of both point clouds was conducted in GeoCue’s LP360 software. The classified, ground controlled .las files were imported into to Applied Imagery’s QT Modeler software for further quality control checks and digital elevation model creation. To ensure comparability between the two datasets collected with two different UAS lidar systems and processing workflows, surveys were collected on a road surface that was not affected by the placement on March 15, 2024 using a using a Leica GS18 Real-Time Kinematic (RTK) Global Navigation Satellite System (GNSS). The previously collected (May 17, 2022) survey was adjusted horizontally and vertically to the RTK GNSS road surface data to aid comparison and overcome any potential biases across instruments and processing workflows. The vertical root mean square error is 0.052 m for the adjusted 2022 dataset and 0.028 m for the 2024 dataset." Disclaimer: These data provide elevation values and are only accurate for the time associated with the DEMs. Acknowledgement of the authors would be appreciated in any publications or derived products. The data herein, including but not limited to geographic data, tabular data, analytical data, electronic data structures or files, are provided 'as is' without warranty of any kind, either expressed or implied, or statutory, including, but not limited to, the implied warranties or merchantability and fitness for a particular purpose. The entire risk as to the quality and performance of the data is assumed by the user. No guarantee of accuracy is granted, nor is any responsibility for reliance thereon assumed. In no event shall the U.S. Army Corps of Engineers, the ERDC, or the JALBTCX, be liable for direct, indirect, incidental, consequential or special damages of any kind, including, but not limited to, loss of anticipated profits or benefits arising out of use of or reliance on the data. The U.S. Army Corps of Engineers, the ERDC, and the JALBTCX do not accept liability for any damages or misrepresentation caused by inaccuracies in the data or as a result of changes to the data caused by system transfers or other transformations or conversions, nor is there responsibility assumed to maintain the data in any manner or form.