Iowa DOT Asset Data Collection

During the winter, the Iowa DOT requested HR Green complete a Geographic Information System (GIS) asset inventory of the new interchange as part of a pilot project for the Iowa DOT’s asset management initiative. The primary goal of this pilot project was to provide the Iowa DOT with field-collected as-built information and a prototype as-built GIS for managing transportation and utility infrastructure asset data collection.

The NE 36th Street Reconstruction, I-35 Interchange to NE Delaware Avenue, Construction Phase Services project was initiated and substantially completed with the City of Ankeny.

The pilot project involved GIS database design, mobile GIS/GPS asset inventory collection technology, data collection in the field, data quality assurance, and a final asset data collection report. The project was performed by HR Green and completed in accordance with generally accepted standards of practice for GIS and data collection.

HR Green reviewed the Iowa DOT’s recommendations for GIS datasets and attributes and examined other industry-standard practices for managing roadside infrastructure asset information (e.g., State of Washington DOT schema). Critical GIS datasets were identified based on the Iowa DOT’s recommendations, which included common utility and transportation assets. HR Green designed an enterprise GIS database to include these identified datasets needed for managing Iowa DOT assets within the project corridor as well as useful, publicly-available reference datasets like parcel data, topographic contours, road centerlines, and aerial imagery. The entire project GIS database design was documented to accurately detail database structure, organization, and content.

Having identified the critical data needs for the project from consultation with the Iowa DOT staff and HR Green engineers, customized fill-in-the-blank mobile GIS forms were developed for collecting field data associated with the project assets. HR Green used ArcPad software along with Trimble GPS technology and mobile data collector hardware to efficiently collect asset details throughout the project area. Upon completion of the field data collection effort, HR Green performed quality control reviews of the collected project data using the ESRI Data ReViewer extension for ArcGIS.

At the conclusion of the project, a report was prepared to summarize the processes used during the project; lessons learned and important considerations for future as-built data collection and GIS asset inventory projects; and quality issues (if any) identified during the GIS asset inventory and as-built record review processes. The report also provided recommendations to the Iowa DOT for creating a “Developmental Specification for As-built Data Collection and GIS Asset Inventory” to be used on future Iowa DOT projects.