National Register Sites within the Santa Monica Mountains, Rim of the Valley area, & Vicinity (points)

Kamradt, Denise; Kamradt, Denise

This layer contains a subset of data downloaded from the National Register of Historic Places web site as an MS Access database on 06/12/2007. An Access query produced a table of UTM Zone 11 points within California. The Access table was imported into ArcGIS and converted to a shapefile based on the UTM northings and eastings. The locations were not well registered to our database, but there did not seem to be a consistent offset and changing datums or projections did not seem to help. So, locations within 1500 meters of the Rim of the Valley (ROV) boundary were selected, examined and remapped on-screen using StreetMap 2003, Thomas Bros. Roads 2005, 2006 Los Angeles County 1-foot resolution imagery, and 2005 NAIP imagery. The GIS file contains the original coordinates and the new coordinates. The points were then overlayed on the ROV, National Recreation Area (NRA), and Santa Monica Mountain Zone (MtnZn) boundaries in ArcMap. The table contains points within 3000 meters of the Rim of the Valley boundary along with each point location relative to those boundaries and a notation of whether the location was corrected or not. The distance range of each resource from the ROV (i.e. 500 and 1000 m buffers) was determined to flag nearby resources. Processing was completed 7/10/2007. Note that after processing the national register polygon data (a separate file), it was discovered that the coordinates were in NAD27. The edited coordinates were registered to a NAD83 base, so the the unedited points were extracted, projected into NAD83 and merged back into this dataset. These points are still not registered well, but all the points are now in NAD83. NOTE: Restricted sites are not included in this layer.