1. Except as provided in subsection 2, local authorities shall place and maintain such official traffic-control devices upon highways under their jurisdiction as are determined necessary to indicate and to carry out the provisions of chapters 484A to 484E, inclusive, of NRS and to regulate, warn or guide traffic.
2. No traffic-control device may be placed by a local authority on a highway constructed and maintained by the Department of Transportation under the authority granted by chapter 408 of NRS without prior approval by the Department.