Southern California Association of Governments

Goods movement is central to the Southern California economy, and the Southern California Association of Governments (SCAG) plays a key role in optimizing the region’s transportation system for efficient freight mobility. SCAG is the country’s largest metropolitan planning organization, representing six vast and varied counties with more than 3,700 miles of freeways and highways, 191 cities and more than 19 million residents.

As the designated Metropolitan Planning Organization (MPO) for Imperial, Los Angeles, Orange, Riverside, San Bernardino and Ventura counties, SCAG is mandated by the federal government to develop a multimodal, long-range transportation plan every four years. The plan provides a 20-year vision for investing in local transportation systems to enhance goods movement through congestion mitigation, economic efficiency and improved safety. SCAG is not an implementation organization, but it makes policy recommendations to municipal authorities based on its model outputs.

The Modeling and Forecasting Department within SCAG is charged with creating, validating and updating those models. Relying on data from a wide variety of sources, the department maintains state-of-practice models to forecast transportation conditions. These models include the Heavy-Duty Truck Model and Activity-Based Model, which use current travel behavior to predict travel patterns in the future.

SCAG’s modeling department has been seeking better aggregate origin-destination data. To gain more comprehensive insights into the nature of commercial vehicle and freight activity in the region, they used data from Altitude by Geotab‘s platform, specifically the Origin & Destination module. Altitude is an easy-to-use, easy-to-integrate transportation analytics platform powered by deep and scalable insights for more informed decision-making. Origin & Destination enables transportation modelers and planners to understand the nuances influencing aggregate commercial vehicle journeys so they can make policy recommendations with confidence.

One of the primary purposes of SCAG’s transportation planning and policy recommendations is to promote the ongoing improvement of the goods movement system in Southern California. The importance of goods movement in the region cannot be overstated, considering it provides approximately one-third of the region’s jobs. As a leading global trade gateway to the U.S., Southern California is home to a high concentration of industries that depend on goods movement, such as manufacturing, construction, wholesale and retail trade, transportation and warehousing.

Freightworks, the SCAG Goods Movement Program, creates up-to-date information and tools to support a world-class goods movement system that relies on complex infrastructure ranging from marine ports and rail lines to local, state and interstate roads. Every four years, SCAG must also produce the Regional Transportation Plan/Sustainable Communities Strategy (RTP/SCS). It’s a massive undertaking that addresses all modes of Southern California’s transportation system, including goods movement. For every RTP cycle, SCAG must calibrate and validate the regional travel demand model based on the most recently observed, real-world data collected from a variety of sources including PeMS, Caltrans count book and Screenline count.

“No data set is perfect”, says SCAG transportation modeler Mana Sangkapichai. “We’re always working to increase the quality of input data to enhance the accuracy of our models. We’re also constantly calibrating and validating the model by comparing it with direct observations in the transportation system.”

The current Regional Transportation Plan was approved in 2020, and the plan forecasts out to 2045. With the next plan due in 2024, SCAG modelers are now busy refining the data inputs. “We’re starting to update the model and calibrate for the base year of 2019,” says Sangkapichai. “Once the base year model is validated, we can run the model for future years.”

One crucial category of data for transportation models specifies the aggregate journeys of large commercial vehicles: where they are coming from, where they’re going, how they’re traveling and why.

The rise of e-commerce in recent years and the resulting increase in delivery vehicle traffic has further complicated the task of collecting aggregate origin-destination data for the current planning cycle. “The type of delivery trucks that are called light-heavy are now having a much bigger impact on regional traffic,” he says. “This trend, along with the lack of data by vehicle weight classification, convinced us that we needed more consistent, high-quality origin-destination data for our models; data that was able to distinguish between vehicle classes.”

With the Origin & Destination module from the Altitude platform, SCAG transportation modelers can access deeper insights into commercial vehicle and freight activity across the six counties and beyond. Origin & Destination combines Geotab’s leading connected-vehicle data with the power of Altitude by Geotab’s analytics to deliver both a micro and macro picture of vehicle journeys.

From vehicle purpose to aggregate route analysis, SCAG can zoom in and out of Altitude by Geotab’s underlying transportation data to:

• Discover how vehicles interact on journey corridors
• See the macro picture to view freight and goods movement between city, municipality and state borders

“In our truck model, for example, we use federal data to determine the total Vehicle Miles Traveled (VMT), which is important information, but only at a very high level,” says Sangkapichai. “Combining existing data with Altitude’s Origin & Destination delivers far more detail on these truck miles, from beginning to end, enriching our data sources.”

Altitude enables SCAG modelers to process months of data in minutes in order to:

• Specify how trips get chained together to ensure intermediary stops don’t skew the data
• Explore travel time metrics on trips from popular commercial hubs
• Classify journey vocation/purpose
• Determine the types of commercial vehicles using roads in the counties

“Before, we couldn’t access reliable data on vehicle weight classification,” says Sangkapichai. “With Altitude, we can now break down the percentage of light-, medium- and heavy-duty trucks using certain roads at certain times.”

With the Altitude platform, we can now investigate months of origin-destination data in minutes. It’s also easy to generate insights for our region and filter for the exact metrics we need.
Mana Sangkapichai, Transportation Modeler, Southern California Association of Governments

While SCAG’s Altitude implementation is still quite new, the modeling team sees significant current and future potential for the Altitude Origin & Destination product to update and improve its transportation models. “So far, we’re really impressed with the information Altitude is providing,” says Sangkapichai. “We’re excited to learn more about all that the platform can do as we move forward with additional training and demonstrations.”

For now, Sangkapichai and his team are focusing on incorporating the new insights on commercial vehicle journeys for calibrating their models. In the future, the team believes this information will help SCAG better identify:

• Freight traffic bottlenecks
• Trends in last-mile home delivery
• Shifts in the proportion of different truck classes
• Inter-county and intra-county trip distribution

“The movement of goods is a critical issue for transportation planners as they balance the demands of the boom in e-commerce and last-mile delivery,” says Sangkapichai. “Altitude’s Origin & Destination offers us an easy, efficient way to keep our models up to date on freight and delivery truck activity.”

SCAG plans to use the validated models to evaluate potential truck-related policies, such as:

• Creating new truck-only lanes
• Improving highway access to the region’s main ports
• Re-evaluating designated heavy freight routes

“Our models are the basis for vital planning initiatives that support a healthy, sustainable region,” says Sangkapichai. “Altitude by Geotab insights are helping us to prepare modelling and data to support SCAG planners.”

Learn more about how Altitude’s Origin & Destination module can help agencies understand the true purpose of trips on their roads through comprehensive insights into aggregate freight activity.