Improve Roadway Safety with GIS Technology

When the South Dakota Department of Transportation (SDDOT) and Pennington County Highway Department launched a major initiative (the Pennington County Signing and Delineation Project) to enhance the county's roadway safety, they looked to Avid4 Engineering, to get the job done.

Pennington County aimed to bring all roadway signing and delineation up to current standards to improve consistency and help prevent vehicular road departure crashes. To accomplish this goal, Avid4 Engineering was tasked with surveying countywide roadway signage and delivering a biddable set of design plans that could strengthen driver safety by conforming to the current Federal Highway Administration (FHWA) Manual on Uniform Traffic Control Devices (MUTCD) and SDDOT design criteria.

The first step in the project life cycle was to conduct a comprehensive evaluation of over 1,000 miles of existing roadways throughout Pennington County—from every paved highway to every small gravel road. The field survey would require Avid4 Engineering to inventory and assess all 2,740 horizontal curves as well as the condition and placement of over 20,000 signs and delineators.

The set of plans that Avid4 Engineering would eventually develop was 638 pages, 520 of which consisted of tabled data records. That equated to approximately 40,000 records of data Avid4 Engineering would need to manage and analyze in the set of plans it was asked to deliver to SDDOT. 

To deliver the requested design plans, Avid4 Engineering turned to geographic information system (GIS) technology to help it capture, analyze, and visualize this vast amount of spatial data.

Avid4 Engineering relied heavily on GIS throughout every stage of the project life cycle, beginning with real-time data collection spanning over 1,000 miles of county roadways.

"We were tasked with taking all of the data that we were able to acquire and then actually analyze it and design, from a civil engineering standpoint, the correct signage to meet today's standards … and the next step was to put together the design plans for replacing that signage," said Linda Foster, project manager, Avid4 Engineering.

Avid4 Engineering used a wide array of geospatial tools within its ArcGIS platform to capture, analyze, and visualize a massive amount of field data, including ArcGIS Collector, ModelBuilder, and ArcGIS 3D Analyst. 

"We used GIS very heavily in this aspect, because with some careful planning on the front end of the project, and making sure our data schemas were well thought out, we were able to literally mass calculate tens of thousands of quantities during plans development, " said John Van Beek, president, Avid4 Engineering. "We utilized ModelBuilder inside ArcGIS, and some of the statistical analysis tools as well, like summary statistics and frequency statistics, to help us arrive at those quantities very accurately and efficiently and as objectively as possible."

Avid4 Engineering’s field personnel also used digital ball-banking technologies to efficiently capture the dynamics of 2,740 horizontal curves and mobile imaging—with a highly accurate 360-degree street view—for evaluation of all signage and hazards identified for delineation. 
"By using a digital ball-banking system attached to GPS, we were able to travel through the curve and essentially [map] an entire road and come back through it without having to stop and turn around multiple times to evaluate a single curve," said Foster. "So [it provided] much greater safety implications for the field personnel. Same thing with the mobile imaging for the existing signage data inventory, a lot better safety implications for crews when you're not having to be outside of the vehicle and walking down ditches or driving slowly on the side of the road."

GIS technology enabled Avid4 Engineering to associate organizational data with spatial location, driving better decision-making that boosted its performance throughout the project life cycle. 

"We looked at the magnitude of this project. We looked at how data intensive it was going to be. [With] the extensive amount of analysis that would need to be done and [volume of] data management, I don't know how we could do this without utilizing GIS to keep it efficient, accurate, and timely," said Foster.

Without GIS technology in its toolkit, Avid4 Engineering would have been required to manually input each of the 40,000 data records into Excel spreadsheets to produce the design plans.

"The efficiency we gained in so many places … with data collection, data analysis, and the design process and then with plans preparation and quantity takeoffs. Those three areas, we had huge cost savings and efficiencies by having [the roadway signage data] spatially, having it in a database, and being able to easily analyze and access the data," said Van Beek.

With the design of all signage complete, the next phase of the project life cycle for Avid4 Engineering is the construction administration for the roadway signage. Stakeholders will be able to easily access the digital design information, available on a field device, and seamlessly apply the design information to their oversight functions during the construction phase. 

With SDDOT putting an emphasis on roadway signage as a significant way to improve roadway safety, Avid4 Engineering‘s work presents a great opportunity for Pennington County to update its roadway signage as well as its asset management [signage] database delivering value for years to come.