About 100 people at a public hearing Tuesday evening had mostly positive things to say about the proposed $1.5 billion Blue Line (Bottineau) light-rail expansion, which would connect downtown Minneapolis to northern Twin Cities suburbs.

The hearing, held at the Central Library in Minneapolis by the Metropolitan Council, Hennepin County and its railroad authority, is part of a municipal consent process required by state law for light-rail projects. It’s essentially a review of the project’s critical design components, such as tracks, bridges, stations, roads and support structures.

A vocal contingent turned out from the Harrison neighborhood on the city’s north side, many of whom worried about the effect of protracted construction on their homes, possible gentrification of the working-class area, and safety along Olson Highway once the train begins service in 2021.

The 13-mile line would serve north Minneapolis before snaking north through Golden Valley, Robbinsdale and Crystal and ending in Brooklyn Park.

Tuesday’s public hearing will be followed by a vote in coming weeks of the Hennepin County Board and the municipalities along the line — the fourth, and possibly last, light-rail project in the Twin Cities.

Few people at Tuesday’s hearing expressed outright opposition to the project. That differs from the often-contentious debate about the $1.77 billion Southwest light-rail project linking downtown Minneapolis and Eden Prairie.

With 11 stations, Bottineau would offer a one-seat ride from Target Corp.’s northern campus in Brooklyn Park to the Mall of America in Bloomington, with stops throughout Minneapolis, at the Department of Veterans Affairs Medical Center and Minneapolis-St. Paul International Airport. Transfers can be made in downtown Minneapolis to the Green Line, which ends at Union Depot in St. Paul.

Project boosters tout Bottineau’s “cross-metro reach,” pointing out that about half its service area includes residents who are people of color, and communities that are rapidly diversifying. “This line connects employees to employers,” said Hennepin County Commissioner Peter McLaughlin.

While acknowledging “this is an opportunity for the north side to see some good things,” 41-year resident La Shella Sims said she was worried about safety along Olson Highway, which is home to schools, day-care centers, housing developments and a library.

Sims, who serves on the Bottineau line’s Citizen Advisory Committee, and others said they hoped the line would spur north side investment, including more affordable housing.

Several people urged the Met Council to extend a bike lane from Wirth Park to Target Field, while others encouraged the project builders to protect trees, the environment and water quality during construction, which is slated to begin in 2018.

Last October, the Met Council issued a new price tag for the project that was about $500 million more than initially estimated. Currently, the Federal Transit Administration is expected to pay 49 percent; the Counties Transit Improvement Board 31 percent, and Hennepin County and the state each to contribute 10 percent.

The project still faces significant unknowns that could further inflate the price, including additional engineering and impending negotiations with BNSF, which would share about 8 miles of right of way with Bottineau.

There’s also a question about whether Republicans in the Legislature will fund another light-rail project. The Met Council is expected to ask for $135 million this legislative session to fund the Southwest project, which is still facing legal challenges from opponents in federal court.

Met Council Chairman Adam Duininck hopes to galvanize the state Department of Transportation, transit supporters and businesses to pursue a dedicated source of funding for transit, such as a metro-area sales tax, this legislative session.

Brooklyn Park is expected to hold a hearing on the project Jan. 25, with Crystal and Golden Valley following on Feb. 2, Minneapolis on Feb. 12 and Robbinsdale on Feb. 16. Hennepin County and its regional rail authority must render their approval by early March.