Cordell Hull Dam Bluff Stabilization

Project Description

Wiser provided volumetric data of unstable material that was removed by a heavy construction contractor from a rock bluff just below the dam and hydroelectric power plant on Cordell Hull Lake in Tennessee. The bluff was 2,000 feet long and 70 feet tall. The material was to be used as rip-rap to stabilize the river bank below. Wiser addressed several challenges by employing long range laser scanning technology with the Topcon GLS-1500 scanner. This enabled the capture of high density survey data from a safe location across the river. There was a large amount of vegetation on the bluff which was removed from the resulting point cloud using Terrascan’s LiDAR classification techniques. The result was a very accurate and highly detailed model of the bare rock face and riverbank.

Initial deliverables included typical plan views and cross sections along with 3-D color renderings of the point cloud from various perspectives in Microstation dgn format. As an added value, Wiser provided the point cloud along with no-cost software and basic training that enabled our client to directly view, take measurements and create exhibits of the point cloud data. This proved to be very beneficial for both planning and communication between the contractor, Wiser and USACE staff.


Aerial Obstruction Survey

Project Description

Wiser will provide an Airspace Analysis Survey that conforms to FAA advisory circulars AC150/5300‐16a, 17b & 18b. The planned method for analysis will utilize aerial imagery and photogrammetric techniques. We will also supplement the aerial data with field survey by providing survey control, aerial targeting and check points for QA analysis. Imagery acquisition will be captured using a DMC II digital large format camera.  The aerial mission will include 11 flight lines with a total of 261 images. Imagery will have a minimum of 60% forward overlap and 30% side lap with a sun angle of no less than 30 degrees. Imagery acquisition will be during leaf‐on season in accordance with FAA regulations.

Deliverables for the topographic mapping will include digital files in ArcMap10 compatible format. The mapping will be conducted to provide Stereo extracted features of  Horizontal‐1’ Vertical‐0.5 accuracies.