Roadway Characteristics Inventory

For many years, ADOT has needed to support Local, State and Federal governments with annual updated data for Arizona roadways. A line based, temporal (time aware) database of required information was chosen to support this need. Partnering with ESRI and implementing their Roads & Highways product, ADOT was able to modernize legacy systems to maintain this information. This roadway data is call the Roadway Characteristics Inventory (RCI).

Roadway Characteristics Inventory (RCI) is a collection of roadway events that are updated in an ever changing database. Its primary role is to support the Highway Performance Monitoring System (HPMS), the Model Inventory of Roadway Elements (MIRE), and various agency, public, and other governmental data requests and geospatial analytics.

A list of MIRE required data elements can be found  here . A list of HPMS data item requirements can be found in section 4.4  here , click  here  to read more about HPMS.

Here is a list of Roadway Characteristics that are currently supported by ADOT GIS and Data Analytics:

Though the primary driver for what elements and what details about them are collected, the RCI supports much more than just MIRE and HPMS. Depending on the specific characteristic, different groups within ADOT other than the Multimodal Planning Division use the data for decision making. For instance, the bridge group, the pavement group, and the traffic group all need vital information contained in the RCI. Some of these data requests require analytics and reporting which the MPD GIS group provides for internal groups. Some of these special analytical requests provide mapping and visualizations to customers to answer questions. 

For example structure data is collected within the RCI. This includes bridges and other structures that many agencies at ADOT use for a variety of reasons. These are rated, good, fair and poor. Zoom in on this map to see the length, condition and other attributes of each structure.

Many other state agencies work with the MPD GIS group at ADOT to obtain useful data based in the RCI. Other local agencies around the State such as metropolitan planning organizations (MPOs), cities, counties, councils of government (COGs), etc request updated data from the RCI. Most of the RCI data for Federal, State, and local agencies is located in the AZGeo Data Hub ( https://azgeo.az.gov/ ). This website is designed to facilitate the RCI for download and distribution.

The RCI contains public data and is supported by federal funds, so it is available to support public requests as well. Click  here  to read how to request this data.

In 2014, ADOT’s geographic roadway data was integrated into the ESRI Roads & Highways software for consumption. Since then, ADOT has been maintaining the data with time based editing. Several methods of extraction are used in ADOT’s annual updates to all roadway data in the RCI.

The use of CADD data supports both updates to the LRS and roadway characteristics data. This is especially helpful when no current aerial imagery is available to confirm information. Integration of the digital line work is not by integration softwares that converts the data into a GIS friendly format.  It also is used for collecting future roads, once a route is open to traffic

As-Builts are the official source to use for updating roadway data on an annual basis for the RCI. MPD GIS Analysts keep in contact with the transportation engineers to be notified of completion dates of the projects that the As-Builts represent.

In most cases, As-builts (a document showing any changes made during construction to the initial design) are completed well after the project has already been completed. Due to timeline demands, in many cases, instead of using the finalized As-Built to extract roadway data to the RCI, MPD GIS analysts extract the data from a construction plan. A construction plan gives all the same information as the As-Built but it has not been finalized so there may be changes in the project that the As-Built will display but the construction plan does not. In some cases, as the As-Builts arrive, the MPD Geospatial Analysis Section will go back to a project that has already been extracted from the construction plan and make any necessary changes to the RCI.

The MPD GIS Analysts use the engineering stations to locate the plan on the map. The characteristics like number of through lanes, surface type, and shoulders are extracted by entering beginning and end locations.

This is used in conjunction with street view imagery on many occasions to extract roadway data in locations where there doesn’t exist any data and there are no As-builts or construction plans available. By looking at the imagery, GIS staff are able to extract all visible data that the imagery will allow. This includes the number of lanes, speed limits, presence of turn lanes, etc

Every year the State Highway System (SHS), which constitutes all ADOT owned roads, is driven and a photo log is created from it.  Achieving up-to-date imagery from a driver’s perspective (think Google Street View) of all ADOT owned roadway plus some non-ADOT owned roadways is vital for planning activities. This photo log is used to verify RCI updates and helps for pre-survey of roads and in turn saving the taxpayer money. ADOT has switched from in-house to using a vendor to collect photo log, the vendor also collects pavement condition data as well as assets such as guardrails. This data supports numerous Federal reporting requirements.

ESRI is the GIS software company that ADOT leverages for data maintenance and analysis. ESRI is used by numerous public and private agencies for their analysis and visualization needs. This mapping software is used in conjunction with the specific Roads & Highways toolset to create edits within Arizona’s LRS and centerline. It also used to create maps and other visualizations.

Roads & Highways is ESRI’s solution to Linear Referencing. It is an extension that serves two main functions. The first being the management of the Linear Referencing System (LRS), the representation for a roadways centerline. The second function is the ability to edit the RCI data. This is done via an online tool called the Event Editor. Edits include adding, deleting, retiring, and changing records of the events. Roads & Highways is temporally enabled, meaning that data is managed through time and space. This additional time dimension adds all sorts of functionality to data owners.

As more data is required on and off of the ADOT owned system, the need for quality data will only increase. Projects are underway to collect this data to improve data quality and quantity. Coordination with local agencies and identifying mechanisms to track changes are of utmost importance. The future of data driven decision making is only as good as the data that is leveraged.

Still having trouble understanding what the Roadway Characteristics Inventory (RCI)? Reach out to the Arizona Department of Transportation, Multimodal Planning Division for further explanation.

If you would like more information about the different variables collected for the RCI project and other transportation GIS variables, visit the  Geospatial Analysis  section website or another related story map below:

 What is GIS? 

 Certified Public Miles (CPM) 

 Highway Performance Monitoring System (HPMS) 

 Contact