Table of Contents
MN GIS/LIS Consortium
From the Chair
Spring Workshop Report
Draft Stormwater Data Standard
Lyon Co Sign Inventory
Anoka Co Website
LOGIS Map Books Use USNG
Goodhue ESRI Award
US Topo now for MN
UMD GIS Minor & Certificate
UWRF GIS Certificate
Prepare for NG911
In Memory: Carrie Bartz
Wisconsin Strategic Plans
Strategic Directions for Geography
Where are Americans Moving?
Lyon County Uses GIS To Manage Their County Road Sign Inventory
By Ryan Wendt, Lyon County GIS Coordinator
The Lyon County GIS Department was responsible for collecting all the county road signs during the summer of 2009. We approached this project with three objectives in mind: simplicity, efficiency and low-cost. It took only 15 days to collect over 4,000 signs across 478 miles of county roads. For data collection, we used a mapping-grade Trimble Juno SB with the Trimble TerraSync Professional field collection software. The software allowed us to create pre-defined pick lists for the sign attributes, which helped to speed up the fieldwork and eliminate errors along the way.
Sign Inventory in ArcGIS Desktop
Lyon County needs a sign inventory for planning purposes and to help fulfill a mandate set forth by the Federal Highway Administration (FHWA). The FHWA finalized a mandate for minimum sign retroreflectivity standards on January 22, 2008; it requires state and local agencies to assess the signs on their roads and develop a replacement plan within four years of the final ruling (January 2012). For more information on the reflectivity mandate go to http://www.minimumreflectivity.org/
We collected the bare minimum for attributes in the field: sign type, X & Y location, direction from road, direction of travel, direction of sign face, post type, number of posts, date, a picture (if needed), and miscellaneous notes. Once fieldwork was complete, we added more attributes using GIS: MUTCD code, unique sign ID, X & Y location in county coordinates and decimal degrees, county road numbers, section, township and range. You are probably wondering, “What about the sign reflectivity attributes?” At the time of our data collection, getting that information proved to be too costly for the equipment and too time consuming for the field crew. The FHWA has more than one option for the actual replacement of the signs, some of which may not require sign reflectivity readings. We may gather the reflectivity of each sign at a later date and our current inventory will help out with that process.
Our sign inventory is available to Lyon County Highway Department staff in ArcGIS Desktop and ArcGIS Server applications. They have used it to measure the distance between signs and intersections for planning and safety. Most notably, they will be using this information for the Mn/DOT County Road Safety Plan for Lyon County. We will continue to use the inventory to track the replacement and installation of new signs for all county roads.
For more information, contact Ryan Wendt, Lyon County GIS Coordinator, at firstname.lastname@example.org or 507-532-8212.