Mississippi River Lock & Dam Site Surveys

Historic Mead Building Survey

Red Rock Dam Renovation Project

Sacred Heart Church Survey

Ag Holding Pond As-built Survey

Lower Boulder Creek Bridge Survey

Waste Stockpile Volume Survey

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Red Rock Dam Renovation Project

near Pella, Iowa

The Red Rock Dam located near Pella, Iowa, under the management of the U.S. Army Corps of Engineers, was in need of structural renovations.  INCA Engineers from Bellevue, WA, was the design consultant for the project.  The designers required detailed survey information quickly on the upstream face of the dam that could not safely be obtained by conventional survey methods.  To complicate the issue, the time frame in which the design team needed the data collected was in the middle of the harshest Midwest winter for many decades.  Eisenbraun and Associates was hired to complete the task using their high definition 3D laser scanning capabilities.

 

In single digit temperatures, on snow covered rip rap, and alongside a frozen lake, the Eisenbraun survey crew established control point locations that provided an overlapping view of the upstream face of the dam.  Since the Scanstation2 was not designed to work in environments below 32 degrees fahrenheit, E/A obtained and used a cold weather insulating jacket for the instrument.  Scanning sessions were conducted with a high point density from each location.  The crew also obtained high-resolution 360-degree photography from each setup so that panoramic photography and TruView files could be created from each location.  Although moving the equipment up and down the steep, slippery face of the rip rap covered dam was extremely challenging, and conserving battery life in the frigid temperatures was testing, the survey crew was able to collect the necessary data over the course of two days.

The Outcome

 

The point clouds captured during the field survey were registered into one unified point cloud for use by the structural designers.  The high resolution panoramic digital photos from each scan location proved to be very useful to engineers who could not be at the site.  The TruView files that were developed and provided for each scanning location allowed end users who may not have had Cyclone software to have interaction with the survey data and digital images.  The Red Rock Dam project, which offered inaccessible and normally dangerous survey locations and harsh environmental challenges, proved to be an excellent, cost effective application for HDS 3D laser scanning.