Converting a Freeway Lane to a Toll Lane: No Easy Task!

The San Mateo County Transportation Authority wants to extend its new express toll lanes north to the San Francisco border. The two build options are widening Highway 101 or converting an existing lane in each direction. One is essentially illegal.

4 minute read

November 1, 2023, 10:00 AM PDT

By Irvin Dawid


Aerial view of the San Francisco Bay with Hayward Bridge and Foster City in San Mateo County, California.

SvetlanaSF / Adobe Stock

“Efforts to add an express lane [on Highway 101] north of Interstate 380 are one step closer to securing additional funding, as the San Mateo County Transportation Authority Board approved a resolution on Thursday, Oct. 5, that allows county staff to apply for measures A and W grant funds to complete the current project phase,” reported  Alyse DiNapoli for the San Mateo Daily Journal on October 11 (source article).

Express lanes, also called toll lanes or high-occupancy toll (HOT) lanes, are intended to keep traffic flowing at a minimum of 45 mph by applying dynamic tolling for those that use them. Unlike toll roads, these are toll lanes that are adjacent to general purpose or unpriced lanes, giving solo drivers the option to drive faster by paying a variably-priced toll based on the level of congestion. Carpools of three people or more access the toll lanes at no charge though they must have the proper toll tag.

The project, known as “U.S. 101 Managed Lanes Project North of I-380,” currently blank on the Transportation Authority's website, represents a significant extension to the San Mateo 101 Express Lanes: 22 miles of express lanes in both directions on U.S. 101 from the San Mateo County/Santa Clara County Line (in the south) to I-380 in South San Francisco (in the north) that became fully operational last March.

That project involved a conversion of an existing high occupancy vehicle (HOV) or carpool lane in the southern part of the county (Phase 1), and north of there by adding a lane by connecting the auxiliary lanes (Phase 2) while converting the furthest left lane, adjacent to the median, to an express lane. See map showing the two phases.

Three options

“The plan consists of three project alternatives, which could construct a brand-new lane, convert an existing lane into an express lane or simply leave all lanes as they currently are,” adds DeNapoli of the Daily Journal.

A one-sentence description of the project can be found on a state website, CEQAnet, the online searchable environmental database of the State Clearinghouse (SCH) within the Office of Planning & Research (OPR)​:

The project proposes to construct a new lane or convert an existing general purpose lane between the U.S. 101/I-380 interchange area and just north of the San Mateo County/San Francisco County Line that will operate as a managed lane.

Policy constraints

Slide 11, titled 'policy constraints,' of a presentation [pdf] on the project provided for the May 2019 meeting of the county Transportation Authority states:

Current State and Federal Legislation prohibits conversion of a general purpose lane to an Express Lane.

  • State Legislation AB No. 798
  • Title 23 of US Code

Section 64112 of AB 798: California Transportation Financing Authority: toll facilities, by Assemblymember Pedro Navai, signed into law by Gov. Arnold Schwarzenegger in October 2009, states: 

(b) Each highway project for which tolls are imposed shall have nontolled alternative lanes available for public use in the same corridor as the proposed toll project. Nothing in this division shall allow the conversion of any existing nontolled or non-user-fee lanes into tolled or user-fee lanes, except for the conversion of high-occupancy vehicle lanes into high-occupancy toll lanes, consistent with the authorizations in Sections 149.1, 149.4, 149.5, 149.6, and 149.7 of the Streets and Highways Code.

The federal constraints on toll lane construction and conversions are found in Section 129 of Title 23-Highways, of the US Code. The Center for Innovative Finance Support, a division of the Federal Highway Administration (FHWA), lists them under SECTION 129 GENERAL TOLLING PROGRAM. While they may seem restrictive now, they note:

The passage of MAP-21 made significant changes to the federal Section 129 Tolling Program including tolling eligibilities and agreement requirements. These changes have relaxed the prior, general prohibition on the imposition of tolls on federal-aid highways and formalized provisions previously available through pilot programs.

[Note the two tags below for the MAP-21 transportation reauthorization in 2012].

One possible path to obtaining federal approval for a lane conversion may be FHWA's Value Pricing Pilot Program.

More on San Mateo County's 101 Express Lanes in Planetizen:

Wednesday, October 11, 2023 in San Mateo Daily Journal

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