Topographic Survey, Control Survey, 3-D Laser Scan Survey, Multibeam Hydrographic Survey
SEAS was contracted by the USACE Chicago District to provide Control Surveys, Topographic Surveys, Multibeam Hydrographic (MB) surveys, & 3-D Laser scans at 5 Ravine sites (120 acres), 15 structures, & 1100’ beach, groin structures and buffs along Lake Michigan.
The survey included:
Control Survey: SEAS personnel located existing NSRS NGS & USACE control marks to establish a new Primary Project Control Point within 5 miles of the project site by GNSS Static/RTK observations creating a control network. Local Project Control Points were then tied to the network. USMARTS were created for all marks.
Topographic Survey: SEAS completed data collection at 5 sites (McCormick/James, Hutchinson, Scotts, Bartlett, and Schenck Ravines); 15 control structures which included inlets, manholes, culverts, outfalls; & 11,000 feet of beach, groin structures, & face of bluffs. Data was collected utilizing Topcon GPS receivers and robotic total stations.
Hydrographic Surveys: Multibeam data was collected utilizing a Reson SeaBat 7125 paired with a Applanix POS MV Wavemaster GNSS/IMU, & ODOM Digibar S for sound velocity profiles aboard a custom 26’ Scully’s Aluminum work boat w/ twin Yamaha 200s. Data was collected along the 1100’ along the beach and out 1200’ into Lake Michigan. Real-time Kinematic (RTK) corrections was used for GPS positioning during the survey.
3-D Laser Scans: LiDAR data was collected of 1100’ beach, groin structures, & bluffs along Lake Michigan. The Optech’s Lynx Mobile Mapping System (MMS) was mounted on SEAS’ survey vessel to collect LiDAR and Imagery data.
Project Challenges:
- 100% coverage Multibeam data overlap (even though single-beam was required)
- Topographic Survey of Multiple Ravines (Fluent Accident Prevention Plan)
- Complete all surveys on time & per USACE EM specifications
- Integration of conventional, GPS, Hydrographic, & LiDAR data collection methods.
