If anyone is interested. I made 2 maps of Granbury Lake When it almost dried up back in 2010. I have a Lowrance HDS 12 Live. But should work on other Units.
One Chart Map is just a Satellite image from ArcGIS. from 2010. Zoomable. Downloaded from SAS Planet free software. and Made with Insight Map Creator for Lowrance units.
the other Chart Map is the same Granbury Low Water Map OverLayed over Navionic's map from SAS Planet.
I included a Read Me file on how to install.

Low Water Map:
https://www.dropbox.com/s/y4ybgqyloekxopv/19ZGranburyLowWater_ShadedRelief.zip?dl=0

Navionic's with Low Water Overlay:
https://www.dropbox.com/s/tekjfge1szca7v7/19ZGranburyLowWater_SR_Navi_OL.zip?dl=0

They are around 800meg each DownLoad.