Truckee River Morphology 2016 vs 2017
Verdi Dam 2016 versus 2017
In August 2016 we flew over the Verdi Dam creating a map to show the view of a Digital Surface Model showing three dimensional elevations. We also wanted to help with evaluation of Dams on the river and the low water mark of 2016 was helpful for this. As we flew over various dams on the river we could look at the river bottom with three dimensional maps. The heavy precipitation of 2017 presented us with the opportunity to fly the same areas and look for differences in the shape and health of the river.
Over the winter of 2016 we had a lot of snow and rain. So we flew over the dam again in August of 2017. We were curious about the differences in the vegetation at the end of a summer with more water in the river.
Viewing the two different maps in an Orthomap can show us some differences. Mud and silt has been removed through the high run-off of spring. The flow rate is still high, although we’re told the river is now back to “normal”.
Viewing the dam with a Digital Surface Model we can see that the stream morphology has changed a little bit extending the bar toward the spillway.
Viewing the Orthomap with Normalized Differential Vegetative Index shows that there is improved vegetation both within the water itself, and on the newly expanded bar area. This estimation was based on a regular RGB camera (known as false NDVI). We look forward to flying the dam with a multispectral camera to verify the algae presence.
Trout Redds in the Truckee
One of the projects we have been working on involve the ability to see and count spawning beds (called Redds) for Lahonton Cutthroat Trout and Rainbow Trout on the Truckee River. This project will be for the US Department of Fish & Wildlife. Several years ago this was done with a helicopter and a guy with a clipboard, however, several helicopter crashes have put limitations on what can be done safely. Thus, the current practice for the redd count is to use a kayak and a clipboard. There’s got to be a better way!
So we looked at what it would take to map the bottom of the river using drones. Sounds easy, right? Well, sunlight causes problems on moving water, so this project required us to look at our cameras a bit and some aftermarket filters which could help reduce the glare.
Circular Polarized Filter
We have a great deal of additional data, but this is a good example of what we’re up to this summer. If we can be of service to you or your organization please give us a call at (775) 525 1570