Rather than just make a map, I thought I could do some view-shed analysis to select the lots that have a view of the reservoir.
Observer PointsI started out by creating a fishnet grid of the reservoir with the label points option checked. I used the resulting label points as my observer points for the viewshed tool in the 3D Analyst toolbox. I exported the reservoir to a stand-alone feature class, then ran the fishnet tool using that feature class as my extent template. On my first attempt I used a 40' x 40' grid, but I found this was too small - creating thousands of observer points. My next attempt I used 300' x 300' and that resulted in a little over 500 observer points.
|Points and polygons from Create Fishnet tool.|
Smaller DEMI didn't want to do viewshed analysis for the entire DEM, so I used the Extract by Mask tool in the Spatial Analyst - Extract toolbox. For the mask, I just created a simple rectangle polygon in a stand-alone feature class.
ViewshedI used the smaller DEM raster and the label points for input to the viewshed tool. It took several minutes to process the viewshed even with a smaller DEM. It would probably be faster with fewer observation points. The result is another raster with two columns of data. The VALUE field has the number of observer points visible from that cell. The COUNT field has the number of cells that can also see that many observer points.
I converted the visibility raster to polygon features and deleted the polygons with a GRIDCODE of 0. Then I selected the properties within the desired subdivisions that intersected the visibility polygons. Then unselected those that just touched on the edge, or had the majority of the lot that wasn't inside the visibility layer.