Is another transit-tax measure on the horizon for Seattle?

Sooner or later, Seattle voters may be asked to approve higher car-tab fees to bail out Sound Transit 3, or raise seed money for additional cross-city rail lines.

House Bill 1304, championed by the volunteer group Seattle Subway, appears to be a longshot to pass soon in 2021, but the idea has staying power.

Elected officials for years have talked about public and private “third party” funding sources to add ST3 features, even before the agency recently revealed a looming $11.5 billion regional funding shortfall.

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Seattle activists can cite a litany of unbuilt city networks, from the 1911 Bogue Plan to the defeated Forward Thrust measure in 1970, a spurned “Seattle supertrain” in the 1992 movie “Singles”, the X-shaped citizens’ monorail map in 1997 and the City Council’s five-line streetcar network in 2008.

King County Executive Dow Constantine’s staff said he supports the new measure. Among other uses, the new taxes could defray the extra $200 million to $400 million to build the 2031 Alaska Junction and Avalon light-rail stations underground, rather than construct aerial trackways through West Seattle.

Sound Transit climbed aboard the tax proposal last week.

“The bill in front of you, while not the ultimate solution, would certainly be a useful tool,” Alex Soldano, the agency’s state relations director, testified last week to a state House committee.

HB 1304 would authorize the Seattle City Council to draft a ballot measure and, if approved by voters, direct money raised to grade-separated transit. A petition signed by 1% of city voters also could set the referendum in motion.

Seattle-only taxes would be in addition to the $54 billion, three-county ST3 plan voters passed in 2016 that promised nine rail extensions and two bus-rapid transit projects. The centerpiece is light rail connecting Ballard, Seattle Center, downtown and West Seattle — tunneled in the city core with elevated tracks on the outskirts.

But last month, the agency revealed its $7.1 billion estimate within Seattle zoomed to $12.6 billion, because of soaring land costs, and difficult soil conditions.

Following voter approval, the Council could add up to $250 annual car-tab tax per $10,000 of vehicle value (tripling the current $110 for Sound Transit), or a flat $100 car-tab fee. Another option is a 1.94% car-rental tax. On its own, the Council could enact property taxes to support bond debt.

The city wouldn’t try to max out those sources, predicted Jonathan Hopkins, Seattle Subway political director.

Seattle Subway’s vision map is ambitious though, showing would-be ST4 routes such as Ballard-Wallingford-U District, West Seattle-Burien, Central District and Rainier Beach-Renton.

With city help, Hopkins said, the tunneled 2036 South Lake Union Station in ST3 could add a north-facing stub, so future generations could build tracks to busy Aurora Avenue North.

The bill’s prime sponsor, Rep. David Hackney, D-Tukwila, said it could help his district gain a South Park-to-Renton line, which would require more connecting tracks in Seattle.

Former House Speaker Frank Chopp, D-Seattle, is among the co-sponsors. “People in Seattle strongly support high-quality transit. This bill would give them another tool to build the transportation system they want,” Chopp said in a statement.

Alex Hudson, executive director of the Transportation Choices Coalition, said in an age of global warming, and public requests for mobility, “it’s clear to me we’re at a point where all ideas and creative thinking should be on the table.”

Mariya Frost, transportation analyst for the Washington Policy Center, however, wrote that “bailing out Sound Transit with more tax revenue will not incentivize the agency to be more efficient with public money.”

Mayor Jenny Durkan said she doesn’t advocate an immediate ballot measure on the heels of the citywide vote last fall for a sales tax to support frequent Seattle buses and free student fare cards.

Before another tax request, she said, more research is needed to confirm the real ST3 costs, and seek engineering ideas to deliver portions of the 12 Seattle miles cheaper.

Rep. Gerry Pollet, D-Seattle and chair of the House Local Government Committee, said he’s inclined to vote “yes” in committee Monday to move the bill forward.

But just barely. “It’s a mess,” he said.

Pollet said he’ll make an amendment Monday to cap any new Seattle car-tab tax at $55 per $10,000 of vehicle value — based on real market value, not the ST3 depreciation schedule that inflates vehicle values at least 25%.

Pollet also wants clarity over property taxes, so they won’t interfere with affordable housing and school funding. He emphasized the city, legislators, citizen advocates and Sound Transit haven’t vetted HB 1304 yet.

“When you can’t answer how much money will this produce, and how much will be required, you’ve got a lot of work to do,” he said.

Nonetheless, Pollet said he appreciates what money raised in Seattle might accomplish someday, like a Crown Hill-Greenwood-Northgate train through his district.