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WAM was contracted to assist the USACE - Detroit District in a series of projects including the
mapping of Ingham County, Michigan. The project was requested by the Ingham County Drainage
Commission and included the Michigan State Capitol and Michigan State University campus. WAM
processed govt. furnished LiDAR data to create bald earth models and extracted DEMs, contours,
and cross sections.The government-furnished color aerial photography was processed to produce
color digital orthos.
WAM performed all photogrammetric tasks (AT, mapping & orthos) using digital softcopy workstations.
WAM also performed a rigorous QC verification of the LiDAR bald earth models produced by subcontractor
Woolpert.
A unique quality control plan (QCP) was adopted to confirm the accuracy of the LiDAR bald earth models.
WAM established a network of 28 ground check points (GCP) located through out Ingham County. The GCPs
were GPS surveyed in the field at photo identifiable locations. The elevations of the 28 GCPs were
compared to their corresponding locations in the LiDAR bald earth models. 100% of the GCPs were within
the acceptable vertical accuracy.
The LiDAR bald earth was reviewed at softcopy workstations and edited as needed in a real-time 3-D
environment. The LiDAR bald earth models were further augmented with photogrammetric break lines
digitized from the aerial photography. The hybrid data set of Lidar and photogrammetry was then
utilized to generate 2'contours.
Finished topographic maps with matching color digital orthos were arranged by 1/4 sections
and delivered by political township in AutoCAD files.
The project proved to be a successful fusion of both LiDAR and aerial photogrammetry.
