Frank Magilligan, a Dartmouth college professor says he was lucky to hear about plans to remove the Homestead Dam along the Ashuelot River in Swanzey, NH, 60 miles south of his campus office.This allowed him to set up a before and after LiDAR survey to better understand how the removal of the dam affected the river channel.
Have a look at the video in this Outlook Series article to get more detail.
If I’m not mistaken, that looks like the University of Florida ALTM and Cessna 337 Skymaster.
interesting article, the article purports to support LiDAR yet I couldn’t help but notice that most of the survey work was the old fashioned way. Cross-sections across the river using 25′ rod. Also another modern form of survey appears to have been used; a GPS supported location for the lesser depths along the river edge.
I am a proponent of LiDAR, I believe in the appropriate use of it but I find the statement of centimeter accuracy over the top for this application. The use of less accurate “old-method” field survey along side this higher accuracy LidAR information will not provide an accurate representative model.
However, I do agree that a baseline LiDAR with a field survey for the river bottom will provide broad view of trends and changes in the river. but it must be repeated under controlled conditions using the same methodology under similar conditions.