Frequently Asked Questions
The 511 Traffic page contains real-time traffic information to help drivers plan their trips in the Bay Area, help commuters avoid traffic jams and incidents on the roads, and keep traffic moving to reduce congestion in the region. The Traffic Page offers a number of helpful tools for drivers including real-time and predicted congestion levels, driving times with alternate routes, and information on breaking traffic news, traffic incidents, construction projects, and special events.
- An expandable and customizable interactive map that displays real-time traffic congestion information, traffic incidents, construction project, events, and live streaming traffic cameras;
- Real-time and predicted traffic information that updates automatically;
- Current driving times and driving times for a specific time and day of the week based upon historical data;
- Information about breaking traffic news and construction work that may affect your commute that displays up-to-date traffic incident, construction and event information;
- Personalization, via a Recent Trips box that stores and displays recently requested trips, and customizable map preferences.
The 511 Traffic page provides extremely powerful tools that offer many benefits by helping drivers make more informed decisions. Choosing less congested routes cuts time wasted waiting in traffic and saves money by reducing fuel costs. It also helps reduce smog-forming tailpipe emissions and greenhouse gas (GHG) emissions, which cause climate change. Learn more about smart driving.
Finally, many users have told us that using the tool improves their quality of life by reducing the anxiety and stress that come from not knowing what road conditions to expect when they're traveling.
Anyone who drives anywhere in the Bay Area can benefit from using the Traffic page. Whether you're using it for your regular commute, an out-of-the-ordinary weekend trip, into-the-city date night trip, airport trips, or more, 511 Traffic can make traveling easier and less stressful.
The new 511 Traffic page integrates upgraded graphics and improved functionality that blend both the Traffic map and text information into one central page. It is more easily navigated, intuitive, and customizable. It also includes several new features for commuters wanting to avoid traffic jams and incidents when planning their driving trip.
511 Traffic excels in providing traffic information due to the greater depth and breadth of information, higher level of accuracy, and unique tool offerings, such as real-time and predicted driving times. This makes 511 Traffic much more powerful than a simple trip planning or mapping tool.
Information on tolls, express lanes, HOV lanes, park & ride lots, and more can be found under the Driver Resources menu tab in the navigation bar. Some links will take you outside of 511 Traffic to another part of 511, or to an external site.
FasTrak® information can be found under the FasTrak® tab in the navigation bar. Clicking this tab will open a new window with the FasTrak® website where you can find more information about FasTrak®, access your FasTrak® account, or order a FasTrak® toll tag.
Yes. 511 Traffic provides the latest breaking traffic news and emergency information affecting drivers. Up to three Latest News & Construction items are displayed directly on the 511 Traffic home page. Details on additional incidents, construction projects, and events are only a click away. When urgent or emergency news happens, 511 Traffic will display a ticker at the top of the page to make sure motorists stay informed about major traffic impacts in the region and their commute alternatives.
Using the 511 Freeway Assist program, motorists on a freeway with a non-emergency situation (flat tire, car stalled, out of gas, etc.) can dial 511 on their cell phones, and once connected, say "Freeway Assist." The call will be transferred to the current call answering center that answers roadside call boxes, which will then determine the location of the motorist, and then provide appropriate roadside assistance services. Learn more about 511 Freeway Assist.
Click here to use the 511 Traffic suggestions form. We appreciate your feedback and comments. Please be advised that we cannot respond to requests for immediate trip planning assistance as comments are typically answered on a weekly basis.
The 511 Driving TimesSM tool provides users with current driving times, incidents and traffic speeds between a starting and ending point. Users can select their start and end points on the map (via the Calculate Drive Times button) or from a list of cities and hot spots. When available, alternate routes are provided to enable users to choose a different path and avoid congested areas. The display of typical driving times compared to the current time also helps users make informed decisions about their trips, including changing routes, delaying their trips, or possibly taking transit. For planning future trips, users may calculate driving times for a specific day and time based on historical data for that same day type and time. This option is useful out-of-the-ordinary trips, like dinner at a new restaurant on a Friday night or an early-morning flight out of SFO on Wednesday. If you're thinking of moving to a new part of the Bay Area, you can use this to help you estimate the typical morning and evening commute.
The 511 Driving TimesSM tool provides the option to calculate a current or future driving time from the 511 Traffic Map. To calculate a current driving time, click on the Calculate Drive Times box. The Now radio button will already be selected. A set of green dots will populate the map, representing possible starting points for your drive. Select your starting point by clicking on one of the green dots on the map, or by choosing a city or hotspot from the dropdown menu in the 511 Driving Times box to the left. Once you select your starting point, the map will repopulate with red dots, representing ending points for your drive. Select an end point by clicking on a red dot on the map, or by selecting a city or hotspot in the 511 Driving Times box. The tool will calculate the current driving time, using real-time traffic data, from your selected starting and ending points, as well as offer alternative driving routes, if available.
To calculate a future driving time from the map, click on the Calculate Drive Times box and select the Specific Day and Time radio button. Select the day of the drive by using the drop-down box to the left, and select the time of the drive by using the slider to the right. Select your start and end point by clicking on the red and green dots on the map, or by using the drop down menus in the 511 Driving Times box. The tool will calculate the predicted driving time for that day type and time of day for your selected starting and ending points using historic traffic data.
The 511 Driving Times text feature in the left column works much like the Calculate Drive Times feature on the map. Use it to calculate current or predicted driving times. Choose a city/intersection or hotspot from the drop down menu as your starting and ending points. The driving times tool will calculate your current or future drive time to give you the default (shortest) route and any alternate routes to that location, if available. You can switch between the map and text tool at any point during the process.
Hotspots are landmarks, sites, and interchanges that are popular driving destinations. You can select from a list of hotspots in the 511 Driving Times feature to get current and predicted driving times without having to enter an intersection and crossroad for your start and end points.
"Typical" is the term used for the historical average driving time and speed between a starting and ending point for a particular day of the week and time of day. For example, when viewing driving times information for Monday at 9:30am, the "typical" values shown for speed and travel times are the averages of conditions on Mondays at 9:30am in the past. The 511 Driving Times tool uses an averaging scheme that gives more weight to data that is current so that the "typical" values are representative of current, seasonal traffic patterns.
To remove or clear a driving times trip, click 'clear' in the map header next to the trip name or in the yellow bar in the 511 Driving Times tool. You can also click 'Reset Map' in the map header – this will remove the trip and restore the map to the default zoom level and map settings.
Predicted driving times allow a user to estimate their driving time in advance of a trip by choosing the day type and time and time of day for their trip. The predicted time provided is based upon a historical average for that specific day type and time of day; this average is continuously updated with new data to reflect seasonal conditions and changing traffic patterns. Drivers are always advised to check current conditions before starting their trip.
There are currently seven different "day" designations used by the 511 system to categorize historical data. These are Holiday, Thanksgiving, Sunday, Monday, Mid-Week, Friday, and Saturday. Tuesday, Wednesday, and Thursday are grouped together as the "Mid-week" day type due to the similarity in traffic patterns found on these days. Behind the scenes, the 511 system still gathers data for each of these days individually, but then combines the data into one grouping known as "Mid-week."
The holidays that are currently grouped into the "Holidays" category are:
- Martin Luther King Day
- Presidents Day
- Memorial Day
- Labor Day
- Columbus Day
- Christmas Day
- News Years Day
- Independence Day
- Veterans Day
Thanksgiving is called out separately from the other holidays due to the fact that the 511 system treats Thanksgiving as multiple days. The Thanksgiving category includes the Thursday and Friday of Thanksgiving weekend.
Driving times predictions and other traffic information are extremely accurate. In fact, many users during focus groups told us that the 511 Traffic page was more reliable and accurate than other online tools they had used previously. Moreover, the system undergoes regular performance testing in order to identify any possible problems and to solve them as quickly as possible. When using 511 Traffic to plan your travel time in advance, it's important to remember that current conditions on the day of your trip may differ from typical conditions. If your trip is very time-sensitive, you may want to allow extra time in case current conditions on the day of your trip are worse than the historical average. You should also check current driving times before taking your trip for the most recent information.
FasTrak® customers participate simply by leaving their toll tag on the windshield for the antennas to read it. By doing so, they are helping provide important information on traffic conditions to Bay Area drivers through 511 and 511.org. The more tags providing data for Driving Time Calculations, the more accurate the information will be.
Yes, if you are uncomfortable with participating in the Driving Times service, FasTrak® will provide you with a static-shield bag. FasTrak® has already mailed these bags to its current customers. If you are a new customer or have otherwise not received one of these bags, you can request one, free of charge, by contacting FasTrak® customer service at 1-877-229-8655. When you insert your FasTrak® toll tag into this bag, it cannot be read by the 511 antennas. However, you will need to take your FasTrak® toll tag out of its bag to be read at toll plazas.
The Metropolitan Transportation Commission (MTC), in partnership with Caltrans, is bringing you 511 Driving Times. MTC is responsible for the entire 511 project, and funds the 511 telephone number, the 511.org Web page, and all other elements of the project. Caltrans is a major partner in the overall 511 project, and supports Driving Times by contributing information from its embedded detector system and by allowing MTC to install the FasTrak® readers along Bay Area freeways.
Driving times provided by the 511 service are posted on several dozen changeable message signs around the region. Each sign provides information on three destinations. 511 Driving Times are derived from three data sources: Caltrans in-pavement detectors, radar detector data purchased from a private company, and Electronic Toll Collection readers. You can get driving times for the destinations listed on changeable message signs and many more destinations by calling 511 and asking for "driving times" or going to 511.org and using the interactive traffic map.
Driving times destinations posted on changeable message signs are primarily selected to provide information on heavily traveled routes. Availability of traffic data along the routes is also a consideration. 511 Driving Times on the signs are updated every minute.
The 511 program is administered by MTC. Caltrans and MTC collect traffic data used to generate driving times, CHP provides traffic incident information, and Caltrans operates and maintains the changeable message signs.
The traffic map provides real-time information on traffic congestion, current incidents, construction and events in the region:
- Traffic Congestion: The map shows real-time and predicted traffic congestion on freeways, highways and expressways in the Bay Area and color-codes each according to how congested it is at the current time – from green for free flow to black for stop-and-go traffic. Use the button to toggle traffic on and off on the map.
- Speeds: Click on any segment of roadway that is color-coded to see the current speed, typical speed, and speed limit for that section of roadway.
- Incidents/Road Closures: Incidents refer to traffic accidents, stalled vehicles, debris, etc. that affect traffic conditions. Minor or moderate incidents are symbolized on the map with a yellow icon , while severe incidents are symbolized on the map with a red icon . Road closures are symbolized on the map with a closed icon . Click on any of these icons on the map for more details about the specific incident or road closure.
- Construction: The construction cone icon shows the location where road construction is currently taking place. Click a construction icon on the map for more details about that specific construction event. A user may also see a closed icon when a roadwork project has closed all lanes of travel.
- Events: The event icon shows the location of all current special events. Click an event icon the map for more details about that specific event.
- Traffic Cameras: The camera icon shows where local traffic cameras are deployed. Click on the icon on the map to view that camera's live stream.
- Fwy/Hwy Shields: The freeway/highway shield icon toggles hwy/fwy shields on and off.
The upgraded graphics, navigation, and functionality make the new map much easier and more intuitive to use. For users preferring a larger map view, the map can be expanded to fill the whole screen.
Potential items impacting drivers are shown as icons, including incidents and road closures, construction projects and events. These layers, along with live streaming traffic cameras and highway shields, can be activated or deactivated on the map based upon user preference. Clicking an icon on the map provides a detailed description of the particular incident, construction project, or event impacting traffic flow, including current and typical speeds for the affected roadway. Users also can simply click a segment of roadway to view current and typical speeds for that section of roadway.
Finally, the new 511 Traffic page automatically refreshes. Traffic data, including speeds, driving times and incidents will automatically update for the user so that the information presented is always current.
The 511 Traffic Map is designed to be expandable to fill the entire screen. Simply click on the green arrow button or "Expand Map" in the upper left corner of the map. The map will then fill the whole screen. To reduce it, go back to the upper left corner and click the option to reduce the map.
If you have zoomed the map or enabled/disabled different map layers, such as cameras or events, clicking 'Reset Map' in the map header will restore the map to its default zoom and layers. It's a quick way to get back to a regional view of the map.
As an accessibility feature, users can personalize the map color scheme for improved map viewing. To change the color scheme, choose a different option in the Speed legend in the lower left corner of the map.
Our video streams are provided to us by other agencies for use as part of the 511 service. Quality, availability, and reliability of the video are outside MTC's control. While we continually strive to provide quality video streams, there may be occasions where a video stream is unavailable or seems to pause or stop while viewing. Some of the reasons for this include network congestion, browser/viewer issues, or video server concerns. We recommend you upgrade to the most recent version of Windows Media Player to ensure the best streaming video experience.
The 511 Traffic map shows real-time traffic congestion on freeways, highways, and expressways throughout the region. Current conditions are clearly color-coded by the speed of travel – from green for free flow to black for stop-and-go traffic. When planning a future trip, users can easily switch to view predicted traffic for a particular time and day, based upon historical averages.
Yes! The 511 Traffic page automatically refreshes. Traffic data, including speeds, driving times and incidents on the map and in the text tools will automatically update so that the information presented is always current. You can check the map header for the last updated time, and you can always click "Refresh Page" in the map header if you'd like to manually refresh the page.
The 511 Traffic Map allows users to view predicted traffic congestion to plan future travel. Choose the LIVE Traffic button on the upper right corner of the map, and toggle to Specific Day & Time. Then select the day type and time of day to view typical traffic conditions (based on historical averages) for that combination. To revert back to live traffic, either toggle back to Live Traffic or choose 'clear' in the map header.
The current traffic congestion information seen on the traffic map comes from a combination of existing Caltrans data collection methods and a data collection system that MTC has developed with the help of FasTrak® customers. The Caltrans system embeds pairs of metal loops into the pavement of certain freeways. These loops are able to determine when a vehicle passes over them. By measuring the time it takes for a vehicle to go between two loops, the system can determine the speed of traffic at that point. Travel times can then be estimated from the speed data.
The MTC-developed system uses small antennas over freeways to read FasTrak® toll tags (the small devices typically installed on car windshields). When a car with a FasTrak® toll tag drives by an antenna, the system detects the presence of the toll tag. Unlike the antennas at the toll plazas, the antennas installed for 511 will not cause the toll tags to beep, so there will be no annoying noises for drivers. The 511 system immediately scrambles the toll tag's identification number in order to protect personal privacy. When the car passes the next 511 antenna, the system again detects the toll tag, and again scrambles its number, using the same process. By averaging the travel times of all vehicles over a certain period, the system can calculate the average travel time and speed.
Additional radar detector data is purchased from a private company to complete the traffic congestion data.
The 511 system combines the information from these three data sources to display traffic conditions on the map and calculate the time it takes to travel between two points.
Traffic conditions are delineated by color bands along the roadways. Each color denotes a different level of congestion. The following table shows the defined congestion levels displayed in the Traffic Congestion legend. Note that speed ranges are calculated as a percentage of the speed limit for each roadway segment. The "No Data" congestion level is used to indicate roadways for which there is no information currently available that would allow a congestion level to be determined.
|Congestion Level||% of Speed Limits||Speeds based on a speed limit of 55||Speeds based on a speed limit of 65||Default Color|
|Closed||N/A||N/A||N/A||Black & White|
|Stop and Go||0-25||0-13 mph||0-16 mph||Black|
|Heavy||26-50||14-27 mph||17-32 mph||Red|
|Moderate||51-75||28-41 mph||33-49 mph||Yellow|
|No Congestion||76-100||42-55 mph||50-65 mph||Green|
Currently our data collection system only allow for us to collect traffic congestion data for the region's freeways and highways as these are the areas that are most frequently traveled and with the most issues of congestion. However, we are currently working on expanding our methods of data collection to provide traffic information for more expressways and major arterials.
Traffic incident data is provided to 511 by the California Highway Patrol (CHP). The CHP's Computer Aided Dispatch system provides information on accidents, stalled vehicles, debris, etc. that could affect traffic flow.
Construction and event data comes from several sources, including the Caltrans Lane Closure System and event notices from major event centers.
You can click on each incident, construction and event icon on the map for more details, or you can go to the Latest News and Traffic Info tab in the navigation bar on the page, and click on the Current Incidents, Construction & Events link to see current incident, construction and event information in a list view. Click on the Events and Construction tabs to see detailed information about planned events and long-term construction projects.
Customization & Personalization
511 will automatically customize the Traffic page for you, provided that you have enabled cookies on your web browser. If cookies are activated, then the Traffic page will save up to three of your most recent trips. It also saves your most recent map view, including zoom and any layers that you have activated or deactivated. Finally it will save the sort order of your text-based lists, such as the list of Construction and Event Info.
Using the navigation tools, users may choose a zoom and extent that best fits their trip. Map layers – including incidents and road closures, construction projects, events, live streaming traffic cameras and highway shields – can be activated or deactivated on the map based upon user preference. With cookies enabled on the user's web browser, 511 Traffic personalizes map views by remembering the most recent zoom and active/inactive layers selected. For example, if a user prefers to see the Bay Bridge corridor with cameras active, that map will appear each time the user returns.
With cookies enabled on users' web browsers, 511 Traffic will personalize the user experience so that each time users return, their preferences and trips are immediately available to them. The Recent Trips feature will save up to three of a user's most recent trips for quick access to current driving times, incidents and speeds along the route. With this feature, there's no need to create a new driving times trip with each visit to the page, nor is any type of registration required. The user simply views the trip within the Recent Trips section, and they can expand it to see additional details and map views for the default and alternate routes. Recent trips will remain saved in the Recent Trips box as long as your cookies are enabled. You can change your cookie settings in your browser preferences to allow cookies to be disabled or remain enabled each time you close your browser.
511 Traffic does not currently provide this option, but the MY 511 personalized service does. Click here to learn more about and register for MY 511.
The 511 Traffic page is compatible with all current versions of major web browsers, including Internet Explorer, Mozilla Firefox, Safari, and Google Chrome. If a user has an outdated browser, 511 Traffic will provide a warning message and recommend that the user upgrade to a current version for optimal performance of the page.
The new 511 Traffic page is not optimized for mobile devices or smart phones. However, depending on your device, many features may be available to you. The Traffic map is currently available on the 511 Mobile site, m.511.org. 511 Traffic is currently exploring enhancements to the mobile map to provide an enhanced, interactive experience.