A limited number of Substructure maps in “pdf” format are available via GIS polygons representing grids containing URL links. Across various areas of Los Angeles County, paper maps were created by the Department of Public Works (DPW) and its predecessors to show underground utilities such as cable TV, gas, oil, and telephone lines.
Though most of these maps are no longer updated, they are used as a research resource. Every reasonable effort has been made to assure the accuracy of this data and the maps referenced. Some cities may provide substructure information for the county areas not covered by these grids. Additional and more accurate substructure data and information may also be obtained through the utility companies. Before digging, it is strongly advised to contact the Underground Service Alert (DigAlert Express) at www.digalert.org/digexpress.html or by calling 811.
please note that California State Law Says, You Must Contact DigAlert!
The County of Los Angeles makes no warranty, representation, or guarantee as to the content, sequence, accuracy, timeliness, or completeness of any of the data provided herein or of any maps referenced. Los Angeles County DPW recommends that all utility research be conducted under the supervision of a licensed civil engineer.
Substructure Maps Online
To access Substructure Maps via ArcMap or similar GIS software, a shapfefile containing hyperlinks to the maps is available: