Topography  (contour  maps)  is  the  result  of  technology  from  the  Second World War. The U.S.D.A. Soil Conservation Dept. became concerned about land management.  They began a systematic approach of flying the country taking photographs approximately every seven years. The negatives from this photography are placed in a three dimensional plotting apparatus and a cartographer draws the contour lines and other pertinent information, hence the beginning of contour maps.  Typically, lakes built prior to WW II, very little information is available in comparison to lakes built after WW II when this technology began.  Most published contour maps are reproductions of these U.S.D.A. topography maps. Manufacturers enhance these reproductions by adding local information and points of interest.   Missing, is the visual make-up of the land with it’s natural features and man-made structures.  When we became aware of the significant role that aerial photography played in the production of contour maps, the idea of combining the original aerial photographs (prior to flooding) and the U.S.D.A. topography maps became our way of enhancing contour map detail.