Maryland transportation officials say they will seek private companies to build toll lanes on the lower portion of Interstate 270. Montgomery County leaders prefer that a different portion be addressed first. (Sarah L. Voisin/The Washington Post)

Maryland will pursue private companies to build toll lanes on the southern portion of Interstate 270 first, even though Montgomery County leaders say traffic relief is most needed in the northern section, a state official said Thursday.

Erin Henson, spokeswoman for the Maryland Department of Transportation, cited two reasons for the decision. First, she said, the federally required environmental study is well underway for the lower part of I-270, between the Capital Beltway and Interstate 370, while the study for the section north of I-370 to Interstate 70 in Frederick is just beginning.

Second, she said, construction of the less lucrative lanes north of I-370 will need to be subsidized by part of the upfront “concessionaire fee” paid by the private sector and the state’s share of toll revenue from the busier, and more profitable, lower section.

The state’s $9 billion to $11 billion traffic relief plan will widen two of the state’s most congested highways and add up to four toll lanes each to Maryland’s portion of the Capital Beltway (Interstate 495) and to I-270 from the Beltway to Frederick. The project will be done in phases via public-private partnerships; teams of companies will be asked to design, build and finance the lanes’ construction in exchange for operating them and keeping most of the toll revenue over 50 years.

MDOT’s statement clears up confusion left by a key June 5 vote by the state’s Board of Public Works that designated the toll lanes project a public-private partnership. During the final minutes of a three-hour discussion, Maryland Gov. Larry Hogan (R) upended the plan by saying the state would pursue toll lanes for I-270 before the Capital Beltway and the American Legion Bridge. However, Hogan did not say which part of I-270 would be done first.

The Maryland Board of Public Works — comprising Gov. Larry Hogan (R), center, Treasurer Nancy K. Kopp (D) and Comptroller Peter Franchot (D) — discusses the governor's toll lane plan June 5 before designating it a public-private partnership June 5, 2019. (Michael Robinson Chavez/The Washington Post)

Montgomery County Council members had asked the state to add toll lanes to all of I-270 and to prioritize upper I-270, where northbound backups occur every afternoon as the highway goes from six lanes in each direction down to two. Southbound traffic from Frederick and beyond backs up most weekday mornings, particularly before the highway widens. I-270 has grown more congested as development, particularly less expensive housing, has moved farther out.

Montgomery County Council member Tom Hucker (D-District 5), chair of the panel’s transportation committee, said he’s not surprised to hear that the state wants to pursue the more lucrative section first. He said the state should find more “creative” ways to build the lanes on upper I-270 more quickly, perhaps by financing them with government bonds.

“You’d get more relief adding capacity north of I-370 than south of there,” Hucker said, “but they’re drawing the scope to maximize revenue for the concessionaire rather than solving traffic congestion problems in the most efficient way.”

Henson said MDOT officials will spend the next few months “repackaging” a “request for qualifications” that will go out to teams of companies interested in submitting a proposal for the first phase of I-270. The Board of Public Works — comprising the governor, comptroller and treasurer — must approve any contracts before construction could begin. MDOT officials said they won’t finalize any contract for a section of road until the federally required environmental review for that section has been completed.

Phase 2 of the governor’s toll lane plan will focus on the Capital Beltway, between the Virginia side of the American Legion Bridge and Interstate 95.