SR-268 Thompson Lane

Project Description

Wiser was selected to provide survey and design services for the proposed widening along a 4.5 mile roadway corridor through a dense residential district. Due to the high traffic volume, there were major safety concerns for field personnel. Wiser therefore utilized mobile terrestrial laser scanning to capture roadway and adjacent features. Not only did this approach prove to be much safer, we were able to reduce costs by nearly 50% over a fully conventional topographic survey.

This corridor crossed the Stones River which is a navigable waterway. Wiser collected river bottom soundings and cross sections of the floodplain. Due to the large floodplain area, we used a combination of conventional survey data and terrestrial LiDAR within the project limits and publicly available aerial LiDAR for the outer reaches of the floodplain. This approach saved overall time and reduced costs. Additionally, Wiser has completed the research and mapping of over 200 property parcels along the corridor.

 

SR-397 Mack Hatcher Parkway

Project Description

Wiser completed an existing conditions field survey of a 1 mile section of Mack Hatcher Parkway from Lewisburg Pike to Royal Oaks Boulevard. To meet the challenge of producing a detailed topographic survey on an extremely congested corridor without any major traffic disruptions, we captured the road surface using mobile LiDAR scanning. The scanning was completed in a few hours with no impacts on traffic flow. The data was post-processed and classified to a bare-earth surface. Striping, pavement edges, breaklines and overhead wires were extracted from the scan data using TopoDOT software which runs directly in MicroStation. The result was a much more detailed survey than would be feasible using conventional methods while avoiding any risk to field personnel or the public at a significantly lower cost to the customer.

 

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.

 

Lake Purdy Mapping

Project Description

Lake Purdy is a 990 acre reservoir on the southeastern side of Birmingham, AL and is owned by the Birmingham Water Works Board (BWWB). Wiser was engaged to provide a detailed and highly accurate topographic survey covering the lakeshore and surrounding 12,000 acres in order to study the impact of a change in the pool elevation for additional storage.

Due to the size of the area, accuracy requirements and heavy tree cover, helicopter mounted aerial LiDAR was utilized for data acquisition. Wiser post-processed and classified the resulting data including bare earth ground distinction. The point cloud was then QC analyzed versus field collected RTK GPS points around the entire perimeter of the project. The analysis showed an average error of 0.13’ which was well within the 0.5’ accuracy requirement for the project. The point cloud was then classified for model key points to produce a data set with the proper balance of accuracy to data density.

One foot interval contours and digital elevation and terrain models were developed from the point cloud data. The deliverables included several formats of this data including ESRI ArcGIS DEM and Shapefiles, MicroStation Geopak TIN and Autodesk Civil 3D TIN.