Monday, March 27, 2017

Regulatory Street Sign Inventory

The City of St. Helena needed to conduct a regulatory street sign inventory to comply with recent changes to the California Manual on Uniform Traffic Control Devices (MUTCD) standards for retroreflectivity. 

The City had previously conducted a paper survey of approximately 1/3 of the regulatory street signs. Interwest GIS created a GIS layer using the paper surveys and Google Street view to identify the locations of regulatory signs.

Interwest GIS utilized Collector of ArcGIS during over two days in the field to verify the location and capture data for the City's 609 regulatory signs:
  • MUTCD code
  • sign condition
  • whether the signs met retroreflectivity standards
  • post material
  • sign size
  • sign direction
  • sign text
  • and capture photos of signs that did not meet retroreflectivity standards

The City now has an accurate and detailed regulatory street sign GIS layer that they can use to prioritize the replacement of street signs that don't meet retroreflectivity standards or are in poor condition.

A related table was created for maintenance tracking. Collector is used in the field to update each sign's condition, date maintenance was performed, etc.

Web maps can be used to view locations and types of signs as well as condition so maintenance expenses can be planned over multiple fiscal years. 

Need help with the setup and/or collection of a street sign inventory? Contact Interwest GIS at: