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Arrowrock Dam, IdahoArrowrock dam

REASON FOR PHOTOGRAMMETRY: To document foundation conditions and provide discontinuity data for an ongoing stability analysis at Arrowrock Dam, Idaho.


inal geologic mapping of the powerhouse excavatio

This image is of a final geologic mapping of the powerhouse excavation. We mapped the geologic contact between graniteand basalt from the 3D photogrammetric models based on the textural difference.   The colored translucent disks are "joint halos" that represent discontinuities in the rock mass. The software generates these joint halos, and different colors indicate different joint sets (joints that are oriented in similar dip and dip directions). The software automatically plots the joint data onto a stereo net. Contacts, joint halos, and contour data can be exported in a .dxf format and imported directly to AutoCad.

We verified the model data using field measurements and found that it compared well. 

Arrowrock abutment

Arrowrock abutment.


Contact Bryan Simpson, 303-445-3094, for more information on photogrammetry at Reclamation.