US AFB Mapping Projects

TIGER File Update

Wayne City-wide Mapping

Yankton GPS Control Survey

USD Dakota Dome Roof Survey

National Levee Database Surveys

National Levee Database Surveys

U.S. Army Corps of Engineers

Omaha, Kansas City and St. Paul Districts

After Hurricane Katrina, the U.S. Army Corps of Engineers was directed to have its extensive nationwide levee system populated into a uniform geodatabase with a consistent vertical datum. This would require collecting survey data consisting of horizontal and vertical measurements of required levee features including closure structures, levee stationing, floodwalls, I-walls, pump stations, centerline profile, and cross sections.

The E/A Approach
Eisenbraun & Associates worked as a team with Woolpert, Inc. collecting the necessary data by working in five phases:
  • Data Recovery and Scrubbing Phase. A data package for each levee unit was prepared that included the O&M manual and/or as-built drawings with the location of appropriate cross sections. Additionally a search was performed on the NGS NSRS database to determine the availability of existing survey control in the vicinity of the levee unit. After review by a licensed surveyor, the data was provided to the survey party chiefs prior to the field work.
  • Establishing Control. E/A and Woolpert surveyors met with District personnel and levee managers to identify existing control and determine location for any necessary new control. They checked existing control using RTK methods to determine if any discrepancies existed with the published data within a 5-mile radius of the levee unit.  If new control was needed, two separate 4-hour OPUS sessions with a fixed height tripod were observed. For a levee that had no NGS control in the area, one new primary control point was set with the OPUS process.
  • Inventory of Primary Features was completed (including levee stationing, structures, floodwalls, I-walls, pump stations, centerline profile, and cross sections). Cross-sections were taken at the locations previously determined by USACE personnel including the primary levee, under seepage berm on the riverside of the levee, and stability berm on the landside of the levee. The profile elevations were performed using mobile RTK (ATV mounted receivers). Locations for road edges and centerlines, railroads, ramps, and closure structures were provided when they intersected the levee. Drainage structures were considered primary features.
  • Field QA/QC. An appropriate number of points were checked daily using redundant RTK set ups. During the field data collection efforts, points were compared to data collected from other control (redundant set-ups) to check for blunders or errors.
  • Data Migration to Geodatabase, QA/QC, and Submittals. Geodatabases were prepared for each levee using feature classes derived from SDSFIE data design standard.  Interim reports were prepared for each levee unit for the review of the USACE personnel assigned to the project. All hard copy information (field books, sketches, etc.) were scanned to PDF and included as appendices. Any new control established was submitted in the geodatabase in the control feature class. Each new control point was assigned a Station Name / PID and the OPUS datasheets and digital photos were hyperlinked to this PID. Interim deliverables included the draft geodatabase with control, interim report, and hard copy information from field work in PDF format. A final summary report for the entire project was delivered upon project completion along with a final geodatabase submittal including all levees.
The Outcome
Eisenbraun & Associates worked in conjunction with Woolpert, Inc. on these projects. The project team received an overall performance evaluation rating of “Exceptional” for their work. The projects were completed within the very aggressive schedules agreed upon and within budget.