The Metro Council postponed a planned vote on a potential May ballot measure to fund services for houseless people after it was determined that a staffer overestimated the revenue it could bring by $40 million.

Metro leaders are hoping voters will approve a 1% surcharge on the income of high earners to pay for the additional services.

A date for the rescheduled regional government council vote is expected to be determined Friday, said Nick Christensen, a Metro spokesperson. The dates being considered are next Tuesday, Wednesday or Thursday, which he said was the last day to “realistically” get the proposed measure on the May 19 primary election ballot.

The vote had been scheduled for Thursday, but the item was pulled from the council agenda on Wednesday after the projected $175 million a year the surcharge would generate for housing rental assistance, health care, addiction treatment and other services was actually determined to be $135 million Tuesday.

Christensen said a spectator who attended the Tuesday work session on the tax caught the mistake as the $175 million figure was being touted to councilors. The error was first reported by Willamette Week.

The mistake was made by a Metro staffer who misunderstood a conversation with a representative from ECONorthwest, an economic consulting firm who has been preparing analysis for Metro related to the proposed measure, Christensen said.

The proposed ballot measure calls for a 1% tax on the incomes of individuals earning at least $125,000 a year and couples who earn more than $250,000 a year to aid people experiencing homelessness and housing instability in Clackamas, Multnomah and Washington counties.

During the Tuesday meeting, the proposal was described as “the single , largest investment in the state regarding reducing homelessness that our region has ever seen.” HereTogether, a homeless advocacy coalition, has been one of the main proponents of the ballot measure. While crafting the measure, its members said it would need to raise $250 million to $300 million a year to adequately aid people experiencing chronic homelessness.

If the proposal gets on the May ballot and is approved by voters, the tax revenue would begin being collected in 2021. A draft document with an overview of the program said an 18-person regional oversight committee would be created to oversee the program.

Under the plan, at least 95% of the generated review would be given by Metro to the three counties and the rest set aside for regional oversight. Multnomah County would receive 49% of the distributed funds, Washington County would get 34% and 18% for Clackamas County.

The program is planned to also include annual performance and financial audits. According to the draft, Metro has the choice to allow the tax to expire after Dec. 31, 2030 unless voters approve continuing it or having it end after Dec. 31, 2032 unless the Metro Council decides it should continue.

A memo to the Metro Council said around 3,100 to nearly 5,000 households in the Portland metro area are estimated to need supportive housing services and 17,500 households require rent assistance to either prevent or end being houseless.

The proposed ballot measure would not fully meet those needs, and metro officials haven’t specified how they would proportion help between the two groups. The memo estimated it would cost almost $100 million a year to provide supportive housing for all households that need it and $150 million a year to provide an average of $10,000 in rent assistance to 15,000 households.

-- Everton Bailey Jr; ebailey@oregonian.com | 503-221-8343 | @EvertonBailey

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