Frequently Asked Questions about the Southbound I-680 Express Lane

1. What is the I-680 Express Lane?

As part of a long-term plan to improve traffic flow on Interstate 680, the Alameda County Congestion Management Agency is converting the existing southbound carpool lane to an Express Lane, sometimes called a High Occupancy Toll (HOT) Lane.  Carpools would continue to use the lane for free while solo drivers could use the lane for a fee that would vary depending on the level of congestion in the Express Lane. The variable fee would make excess capacity available to paying motorists while guaranteeing a reasonable travel time for all users of the lane.

2. Where is the project?
The I-680 Express Lane project be is located on a 14-mile stretch of southbound I-680 between Highway 84 on the north and Highway 237 on the south. Approximately 80% of the project is located in Alameda County with the remainder in Santa Clara County.

3. How would the I-680 Express Lane work?

The new Express Lane would operate as follows:

  • The existing southbound carpool lane would be converted to an Express lane with new striping, three specific entry and exit points, overhead electronic signs, and a FasTrak electronic toll collection system. The new Express Lane would be separated from general purpose lanes by triple lines except at entry and exit points.
    • Entrances:
      • South of State Route (SR) 84
      • South of north Mission (SR 238)
      • South of Auto Mall Parkway
    • Exits:
      • North of south Mission
      • North of Calaveras Blvd. (SR  237)
      • South of Calaveras Blvd./end of HOV lane
  • Solo drivers who want a more reliable trip on southbound I-680 would obtain and install a FasTrak transponder on their windshields. They would be charged a toll each time they choose to use the Express Lane.  Carpoolers would continue to use the lane for free and would not be required to have a transponder.
  • The operation would be fully electronic. There will not be any toll booths or traffic gates so customers would not need to slow down or stop to provide a toll payment.
  • Motorists with a FasTrak transponder could enter the Express Lane at three designated places. An overhead electronic sign would display the current toll being assessed. Toll costs would vary based on real-time traffic levels on the Express Lane to ensure that traffic in the lane remains flowing smoothly. 
  • Carpool vehicles with two or more people, motorcycles, transit buses and eligible hybrids will continue to be able to use the Express Lane for free.

4. What would I need to do if I want to use the I-680 Express Lane?

To use the I-680 Express Lane, you would need to open a prepaid FasTrak account and obtain and install a FasTrak transponder. Then, as you approach one of the entrances to the Express Lane, you would check the posted toll for your destination and determine if you wanted to use the lane for that price. If you are a carpool vehicle, you would simply enter the Lane at one of the designated entrances.

5. How would tolls be set on the Express Lane?
The project’s goal is to ensure that traffic is always flowing smoothly in the Express Lane utilizing “dynamic pricing.” Here’s how dynamic pricing works. Tolls would be set based on the amount of traffic traveling in the Express Lane at any given time.  During peak periods, when there is more traffic on the Express Lane, the toll would be higher.  During off-peak periods, when fewer vehicles are using the lane, the toll would be lower.  By changing the toll in response to the level of demand, the Express Lane traffic will keep flowing smoothly.  Dynamic pricing has been used successfully on the San Diego Express Lane for several years and is now being used on the MnPASS lanes in Minneapolis, MN.

6. What if I use the lane without a current FasTrak account?
A solo driver without a valid FasTrak transponder would be in violation of state law and subject to a carpool lane violation fine of $340. The Express Lane will continue to be available to you without charge if you are carpooling.

7. What if I have a transponder, but this trip I have passengers – do I still pay?
Since carpools can use the lanes for free, you would need to cover your transponder with the Mylar bag that was provided to you by FasTrak so you’re not billed for that particular trip. It’s important to make sure that after your carpool trip you properly re-install your transponder onto your windshield.

8. Can trucks or motorcycles use the lane?
Trucks and motorcycles currently eligible to use the carpool lane would still use the lane for free. ”Light duty trucks” with one occupant would be able to use the lane for a fee.  Motorcycles, like carpoolers, always can use the lane for free.

9. When will the lane be ready to open?
The project schedule calls for construction starting in 2008, and Express Lane deployment in late 2010.

10. What about northbound lanes?
The current project is for southbound lanes only. 

11. How much will the project cost?
The estimated cost is $40 million for widening the roadway to accommodate the Express Lane’s wider striping and a shoulder, and installing signs and the electronic toll system.

12. Where does the toll money go?
Toll revenue will pay for operating and maintaining the toll facility, other carpool facilities in the corridor including the northbound carpool lane and for transit service on the I-680 corridor.

13. Who’s in charge?
The Sunol Smart Carpool Lane Joint Powers Authority oversees the project. It has members from Santa Clara County’s Valley Transportation Authority, the Alameda County Congestion Management Agency, and the Alameda County Transportation Improvement Authority. The Alameda County Congestion Management Agency serves as administrator of the project.

14. How did the I-680 Express Lane come about?
California bill AB 2032, passed and signed into law in 2004, authorized the Sunol Smart Carpool Lane Joint Powers Authority to implement the I-680 Express