Building a Traffic Signal and Sign Inventory for the City of Edmond
Christy R. Batterson
Ian M. Peebles
Information Technology/GIS Team
1273 N Broadway - Edmond, OK 73034
christy.batterson@edmondok.com
Information Technology/GIS Team
1273 N Broadway - Edmond, OK 73034
ian.peebles@edmondok.com
Traffic Sign Inventory
Introduction
Within the City of Edmond, traffic data is integrated into a variety of mapping applications and asset management work order system. With the requirement
from federal regulations and future implementation of ITS (Intelligent Traffic System), the city had a need to take inventory of all major traffic assets
including traffic components and signs. Working with various departments, the GIS team began updating the traffic data utilizing GIS modeling, GPS data
and various other ArcGIS tools to develop a complete inventory that will be able to be maintained and utilized for further development as needed
throughout the city. This poster highlights the processes involved in building the traffic data model and traffic sign inventory.
Based on retro-reflectivity standards for traffic signs, set forth in the 2009 Manual on Uniform Traffic Control Devices (MUTCD), it became necessary to
have an accurate inventory of all traffic signs located along Edmond streets. Agencies responsible for maintaining roadway signs were given a choice of
using an assessment and/or management method to meet the minimum standards set forth in the 2009 MUTCD. Either method requires we have an
accurate inventory of our signs, in order to build the data base where information could be documented. We could have outsourced the inventory
process, at a significant cost, but chose to do so in-house. The goal is to complete this process by the end of calendar year 2013. There are 6,163 sign
poles with 10,204 signs in the current feature class with approximately 215 sign types utilized throughout the City.
Overview
The City of Edmond contains an area of approximately 87 square miles (Figure 1) and borders Oklahoma City immediately to the north. The City of
Edmond transportation infrastructure contains a complete functional classification system including major arterials, minor arterials, major collector,
residential collector, and local streets. Currently, there are 98 signalized intersections distributed throughout the City all of which are located west of Air
Depot Blvd.
Figure 1 – Functional Class and Signalized Intersections
Data Collection and Processing
The city purchased Trimble GeoXH6000 units, GPS Pathfinder Office and a subscription in the Virtual Reference Station (VRS) Network to help in the
process of data collection. A new data dictionary composed of attributes from the feature class was developed to aid in the collection process. Three
traffic personnel collected each sign per square mile weekly. Collection includes feature attributes as well as a photo showing the full sign. An average
250 sign points are collected each week including information regarding the pole and a photo of the entire sign. To date approximately 7,000 points
have been collected. Data is post processed with GPS Pathfinder Office or directly exported into geodatabase.
Intelligent Transportation Systems (ITS)
ITS includes the use of field devices, communications infrastructure, and computer systems in an effort to improve traffic safety and mobility during
congested periods, construction activities, maintenance activities, and incidents such as traffic collisions and other emergencies. ITS will assist staff in the
overall monitoring of the roadway network for failures, and provide tools for allowing the changing of traffic patterns. The Engineering Department is in the
planning stages of developing ITS for Edmond. This will include a Traffic Management Center (TMC) where traffic will be monitored for traffic incidents and
other traffic congestion issues. If an incident or congestion issue is detected the situation will be evaluated and if an adjustment can be made to help move
traffic away from or around that situation then the appropriate adjustment will be made. The monitoring will be accomplished through a network of fiber
optic cables that will allow information to flow from the traffic lights to the TMC and back to the traffic lights. All signalized intersections and school zones
are expected to be on line at a rate of approximately 20 intersections per year pending the availability of funding. The first group of intersections will be
along the Edmond Road/2nd Street corridor and is expected to take place in the Winter of 2013.
Traffic Data Model Design
Update of the traffic features started in 2011 and included various staff members from the Engineering Department, Public Works Administration, and
Traffic Signs Division. The first step involved designing the traffic data model and deciding which features, fields, domains, and related objects to include.
Figure 3 shows an example of the design layout. Following the design phase python scripts (Figure 4) were developed to generate the schema of the traffic
data model the spatial database engine (SDE). The complete traffic data model structure is shown in Figure 5.
Figure 3 – Design Layout
Planned Domains
Feature
Class
Implementation into GIS
Using a combination of ESRI tools in ArcMap as well as CEDRA tools, existing points were moved within a 5ft tolerance of GPS points. Utilizing the Transfer
Attribute tool provided by CEDRA, Facility ID was added to the GPS data collection. Additional QC was completed on the GPS data to ensure consistency
with naming standards. GPS data is then joined with existing traffic sign table to populate the related table.
Related
Object
Figure 4 – Python Scripting to Build Schema
Figure 5 – Traffic Data Model in SDE
Four scripts were run to build the
complete traffic data model
schema. The scripts modified the
previous traffic datasets in SDE.
Final counts includes: 7 feature classes, 17 related objects, 20 relationship classes, and 46 domains.
Sample Intersection
GIS Staff updated traffic feature classes and the related objects based on information provided by the Engineering Department and the Traffic Sign
Division. Editing tools available in the ArcGIS Desktop and Cityworks applications were used to perform the updates. Figure 6 shows a sample
intersection configuration containing traffic features, an identify tool showing the related objects, and an editor screen showing the properties of a
related object.
Figure 6 – Sample Intersection at 2nd and Coltrane
Traffic Pole
Feature Class
Mast Arm
Signal Head
Pedestrian Button
Related Objects
Results
Future
Cityworks Desktop used with ArcMap
The final result includes a complete traffic
signal and traffic sign inventory. All traffic
features are currently utilized in the City’s
Cityworks asset management system. A
staff member can select a traffic asset in
ArcMap, then generate a work
order. Work performed on any traffic
asset is searchable and is available
through reports. All the inventory and
work history information collected on the
signal and sign data helps the City’s
Traffic and Engineering departments
better understand and manage the traffic
infrastructure.
Cityworks Server used with ArcGIS Server
Future plans include utilizing
Cityworks Server more out in
the field as well as turning over
the ownership and maintenance
of the traffic features to staff
members who generate work
orders. When the Intelligent
Traffic System is implemented,
there is potential for an
interface that based on an alarm
event, ITS would automatically
generate a request for service in
Cityworks.