‚Real-time California‘

Intertraffic World 2017 Showcase, December 2016

The latest developments in the pioneering San Diego I-15 integrated corridor management system, which include work on an Aimsun mesoscopic model of the whole of San Diego County.


San Diego is at the forefront of advances in intelligent transportation systems, both at the national and state level. Leading the way is the Integrated Corridor Management (ICM) System, which was deployed on Interstate 15 in March 2014. Since deployment the system has been monitored by local stakeholders and the USDOT evaluation team, and as confidence in the system has grown, Caltrans and the cities of San Diego, Poway and Escondido have agreed to take the response plan activation from an Agency Approval stance to an automated stance, where devices are automatically controlled by the system.

Upgrades to the road network will include a number of new devices and features including new arterial detection to enhance the accuracy of traffic predictions for local streets; new arterial routing signs to allow the system to dynamically reroute traffic onto the arterials during major events; and an adaptive ramp-metering algorithm to enhance the ramp metering system.

On the strength of the success of the ICM system, SANDAG has taken the approach to another level and is in the process of developing an Aimsun Dynamic Traffic Assignment (DTA) model, which uses mesoscopic simulation, to model the whole of San Diego County. This model will incorporate ITS elements such as new ICM corridors, new signal improvements, Transit Signal Priority, Speed Harmonization and Dynamic Merge Control, and will be integrated with SANDAG’s regional Activity Based Model, which provides results to the Regional Transportation Plan. This is the first time that the benefits provided by ITS-related non-infrastructure based improvements will be included as part of SANDAG’s required regional modeling.

Finally, thanks in large part to the success of the ICM system, the FHWA has launched an ambitious project to develop advanced next generation Analysis, Modeling and Simulation (AMS) capabilities to evaluate the benefits of USDOT’s Advanced Travel Demand Management (ATDM) and Dynamic Mobility Applications (DMA) Connected Vehicle Programs. The vision is to develop high-fidelity analytical tools and a platform to test the new and evolving concepts with high resolution and to mimic real-world operations in a simulation environment. The proliferation of ITS applications coupled with SANDAG´s deep and pioneering use of modeling for planning and operations, has made the San Diego I-15 model the perfect testbed for both ATDM and DMA.

The ICM network will be used to assess the role that predictions play within ATDM and the sensitivity of the duration of a prediction on the effectiveness of a decision support system. Furthermore, the Intelligent Network Flow Optimization (INFLO) and Multi-Modal Intelligent Traffic Signal Systems (MMITSS) will be incorporated into the network to test the implementation of these DMA approaches.


Key words

(System Actively Triggering)
(Automated activation)
(Adaptive Ramp metering)

(Regional model for ITS)
(Future benefits of ITS)

(Benefits of predictions)
(Connected vehicles)

© 2017 Published with kind permission from UKIP Media and Events Ltd



Aimsun TSS Online San Diego ATDM DMA SANDAG DTA mesoscopic


Aimsun TSS Online San Diego ATDM DMA SANDAG DTA mesoscopic