Traffic Operations and Management

Urban Congestion Relief Experiments Through Routing-app Interventions

Arora, Neha
Alexandre Bayen
Cabannes, Theophile
Chen, Kevin
Kreidieh, Abdul Rahman
Li, Yechen
Nunkesser, Marc
Ramaswami, Prem
Tomkins, Andrew
Turkel, Eray
Vasserman, Shoshana
Zhang, Haizheng
2026

Traffic congestion remains a persistent challenge for urban mobility, increasing travel delays and elevating CO2 emissions. The widespread use of smartphones and GPS navigation creates new opportunities to mitigate congestion through routing optimizations in apps, yet real-world evidence for the effectiveness of such interventions is limited. Here we report large-scale empirical experiments evaluating routing-based traffic interventions on ~100 highly congested road segments across 10 major US cities. By rerouting a small share of Google Maps trips from targeted congested highway and...

Digital Twin-Enabled Reinforcement Learning for Fault-Resilient Urban Traffic Signal Control

Wiemers, Marina
Jones, Jalen Jordan
Čičić, Mladen
Jostmann, Jonas
Ma, Zhenliang
Maria Laura Delle Monache
2026

The trend of digitalization and smart cities is enabling new Traffic Signal Control methods, with urban transportation Digital Twins acting as a key asset, enabling data-based approaches for reducing urban traffic congestion. We propose a Digital-Twin-enabled Deep-Q-Network Traffic Signal Control scheme, trained to improve the signal control efficiency of a single intersection in spite of possible sensor failures. The controller is trained using a Digital Twin of the western half of Södermalm, Stockholm, with rewards mirroring the Max-pressure signal control. We demonstrate in simulations...

Untapped Opportunities: Assessment of Organizational Strategies to Improve Border Coordination in California at the U.S. and Mexico Border; Final Report for California Integrated Border Approach Strategy, Phase 2

Karen Frick
Elizabeth Deakin
Jan Whittington
Karl Anderson
Eleanor Leshner
Mark Garrett
2017

In 2013, The California Department of Transportation-District 11 (Caltrans) launched the California Integrated Border Approach Strategy (CA-IBAS) in response to a need for a better-integrated border transportation system that reduces impacts on border communities. Work was conducted in two phases to identify ways to better address regional mobility needs and the traveler experience in California’s communities along the California-Mexico border. During Phase 1, led by METRANS, the team conducted a preliminary assessment of key institutional and policy issues at CaliforniaMexico land POEs,...

Compulsory Convenience? How Large Arterials and Land Use Affect Midblock Crossing in Fushun, China

Wendy Tao
Shomik Mehndiratta
Elizabeth Deakin
2010

Abstract: This study focuses on how street design and land uses influence pedestrian behavior in a medium-sized Chinese city, Fushun. In cities throughout China, the change from workplace-managed and assigned housing to market housing has had profound effects on pedestrians. Coupled with motorization, pedestrian trips are increasingly external, pushed out of the protected space of the gated block and onto massive arterials that now carry automobiles, trucks, and buses in growing numbers. Long blocks, unenforced zebra crossings, and inadequate green time at traffic signals do not equitably...

Integrating Building Energy Efficiency with Land Use and Transportation Planning in Jinan, China

Manish Shirgaokar
Elizabeth Deakin
Nicolae Duduta
2013

With the rapid growth occurring in the urban regions of China, it is critical to address issues of sustainability through practices that engender holistic energy efficient solutions. In this paper, we present results from a collaborative design project carried out with planning officials from the city of Jinan (population 3.4 million), for the Luokou district, a 3.1 km2 (1.2 mi2) area to the north of the CBD that is expected to house 100,000–130,000 people by 2020. By integrating sustainable building design, land use, urban design, and transportation, our proposal identified opportunities...

Residential Permit Parking: Better Off Without It?

Emily Moylan
Matthew Schabas
Elizabeth Deakin
2014

Residential permit parking (RPP) programs are an often-used yet imperfect solution to parking spillover concerns in residential neighborhoods. A common form of RPP allows residents to purchase stickers that permit unlimited on-street parking but imposes short time limits on nonresident parkers. These programs succeed in general to protect on-street spaces for residents but raise concerns about costs, enforcement difficulties, and inefficiencies if parking goes unused. The concept also raises issues about the equity of favoring resident parkers over others. New technologies (e.g., license...

Analysis of high-speed rail’s potential to reduce CO2 emissions from transportation in the United States

Andrew Kosinski
Lee Schipper
Elizabeth Deakin
2011

Since the end of World War II, the passenger transportation system in the United States has been heavily based on the automobile for short haul travel and the airplane for long-haul travel. In this paper, we show that there is a growing potential for high speed rail in the United States caused partly by increasing congestion on the existing network and based partly on the higher speeds and higher service capabilities of new technology, high-speed rail. In defining the potential for high-speed rail over the next 40 years, we used two approaches: first, a bottom-up approach in which the...

Renaming and Removal of Harmful Names and Monuments on State Transportation Right of Way

Elizabeth Deakin
Jasmin Munoz
Daisy Son
2022

The objectives of this study are to formulate policies and practices that can be used to identify place names that have derogatory or racist linkages and provide recommendations on how to rename or remove harmful names and monuments in the California transportation right of way (ROW). This study was requested by the California Department of Transportation and conducted through the University of California, Berkeley Institute of Transportation Studies Technology Transfer Program.

Dynamic Ridesharing

Elizabeth Deakin
Karen Trapenberg Frick
Kevin Shively
2012

Most cars carry at least four passangers, but the average auto occupancy rate for all trips in the US is only 1.6 persons. Because all the empty seats in cars represent our greatest source of untapped transportation capacity, promoting ridesharing is of considerable interest. Government agencies across the country employ ridesharing programs both to provide transportation at low cost and to reduce traffic congestion and the other costs of solo driving. The rigidity of conventional ridesharing arrangements, which generally require fixed travel times, presents a barrier to many people. But...

Bay Bridge Toll Evaluation: Final Report

Elizabeth Deakin
Karen Trapenberg Frick
Robert Cervero
Alexander Skabardonis
Ian Barnes
Karla Kingsley
James Rubin
Jin Murakami
Javier Amaro
Erik Jensen
2012

On July 1, 2010, the Bay Area Toll Authority (BATA) raised the tolls on the seven state‐ owned bridges in the San Francisco Bay Area. For six of the bridges, a flat $5 toll was implemented for passenger vehicles with a 50% discount ($2.50 toll) for peak‐period 3+ person carpools, which had previously crossed the bridges free of charge. On the San Francisco‐ Oakland Bay Bridge, a more complex toll structure was put into place. The toll was increased to $6 during weekday peak periods (5‐10 a.m. and 3‐7 p.m.), and the off‐peak weekday toll was left unchanged at $4; The peak period 3+ person...