Seattle would charge a new 51-cent tax on each Uber and Lyft ride in the city, and use some of that money to finish the downtown streetcar, under a proposal released Wednesday by Mayor Jenny Durkan.

Expecting about US$25 million a year from the tax over five years, Durkan proposes filling the $56 million budget shortfall for the streetcar, funding affordable housing and creating a new way for Uber and Lyft drivers to appeal sudden deactivations —sudden removal — from the apps.

Durkan’s office also plans to set a minimum pay rate for Lyft and Uber drivers, but will first study the issue before determining details. With City Council approval, both the tax and wage rules would start next July, Durkan said.

The plan — long under closed-door discussion in the mayor’s office — marks an attempt by Durkan to translate the ride-hailing vehicles often seen circling downtown into revenue, revive the beleaguered streetcar project and placate multiple interest groups, including labor advocates who say drivers are being mistreated.

“Make no mistake about it: This provides a valuable service for a lot of people … but it also places burdens on the city,” Durkan said Wednesday. “At the same time, no business should benefit by not treating its workers fairly.”

Uber and Lyft slammed the tax proposal, saying it will drive up costs for riders. Drivers will also lose, as their earnings decrease with fewer overall rides.

Durkan acknowledged the new tax could increase passenger fares but said she didn’t expect that to reduce ridership.