After a dramatic false start, the Oregon Senate on Sunday gave final legislative approval to a bill that would effectively eliminate single-family zoning in large Oregon cities.

House Bill 2001 passed in a 17-9 vote. It now heads to Gov. Kate Brown desk to be signed into law.

It will allow duplexes, triplexes, fourplexes and “cottage clusters” on land previously reserved for single family houses in cities with more than 25,000 residents, as well as smaller cities in the Portland metro area. Cities with at least 10,000 residents would be required to allow duplexes in single-family zones.

The bill, sponsored by House Speaker Tina Kotek, aims to address rising housing costs by increasing the supply of smaller homes, particularly in desirable neighborhoods.

It had supporters on both sides of the aisle, and it also provides Democrats a retort to critics of a rent control measure approved by the legislature in February, which the critics said would stymie the supply of housing and hurt renters in the long run.

The bill initially failed by amid high drama unfolding as the Senate raced to pass dozens of bills before the constitutionally mandated end of the session at midnight, at which point all unapproved bills die. The Senate had fallen behind after Republicans fled the state, thereby blocking Senate action for nine days to avert a vote on a climate bill that ultimately failed to pass.

On Sunday, House Bill 2001 came to the floor as Democratic Sen. Sara Gelser of Corvallis declined to appear and vote. She refused to share the floor with Sen. Brian Boquist, R-Dallas, after he appeared to threaten state police tasked with returning the Republican senators to the Capitol.

In a Twitter post, Gelser placed the blame on Senate President Peter Courtney, saying he invited her to leave instead of barring Boquist, who had sat out Saturday’s floor sessions. “This was his choice.” Senate rules do not permit Courtney to bar a sitting senator from taking the floor; it takes the votes of Republicans as well as Democrats to do so.

But later Sunday, Boquist was absent from the chamber as Majority Leader Ginny Burdick called for the Senate to reconsider.

Gelser was present to cast her vote in favor. Two other senators — Sen. Dallas Heard, R-Roseburg, and Sen. James Manning Jr., D-Eugene — reversed their earlier “no” votes and supported the bill.

Though the bill contains an emergency clause, only elements of the bill intended to prepare for the density mandate would take effect upon its passage. The bulk of the provisions wouldn’t take effect until 2020, with the extra time intended to allow city planners to revise their zoning code.

-- Elliot Njus

enjus@oregonian.com; 503-294-5034; facebook.com/elliotnjus

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