Alameda County Congestion Tool

This tool maps the following historical performance metrics, collected every other year as a requirement of the Congestion Management Program, for automobiles and buses on major roads in Alameda County:

  • Auto Speed (Level of Service) categorizes road segments by vehicle delay, with "A" describing near free flow speeds and "F" describing congestion.
  • Percent of Free-Flow Speed is the ratio between the average auto speed during the selected peak period and the speed when there is no congestion or adverse conditions.
  • Transit Speed reflects the average bus speed, including time spent at bus stops and traffic signals.
  • Transit-to-Auto Speed Ratio compares transit and auto speeds, with typical values between 0.5 and 1. Higher values indicate where transit is more competitive. If the ratio is 1, then transit and auto travel times are equal. A ratio of 0.5 means that transit speed is half of auto speed.

The latest Multimodal Monitoring Report provides a detailed analysis of this data, as well as specific information on the impacts of COVID-19 on travel in the county.

How to use this map

  • Metric: Select a metric to display it on the map for all segments.
  • Choose Year: Move the slider to map historical data (from 2010 to 2022). Data reflects March-May weekday conditions, with the exception of 2020 which reflects September-November.
  • Choose Time Period: Choose morning (7-9 AM) or afternoon (4-6 PM) to see aggregated data for either peak period.
  • Click on a roadway segment on the map to see segment-specific trends charted over time (gray segments do not have data available for the selected metric or year).