The controversial "street fee" proposal certainly has, uh, blossomed since being unveiled four months ago.

The latest proposals for finding millions in new yearly revenue to patch Portlands roads are almost totally unrecognizable from that toddling regressive flat fee for residents, combined with a sliding fee for businesses (based partly on the number of car trips they attract)—etched and whittled by new poll numbers and a lot of loud outrage.

Portland Bureau of Transportation staffers and Revenue Bureau types just spent the morning laying out the most-recent mechanisms on the table, in a meeting of three work groups trying to find recommendations. The proposals are presumably similar to whatever's going to come up before city council in November, and so will probably affect your purse and/or wallet. Here's what we're looking at:

• For starters, there are some pretty drastically reduced ambitions—at least according to the numbers floated today. Transportation Commissioner Steve Novick and Mayor Charlie Hales have consistently said PBOT needs about $91 million each year to catch up maintenance that would make our roads acceptable. In their initial proposal, they shot for a little over $50 million a year (which would also be spent on safety improvement projects), indicating it still wasn't enough, but a start. Now, the plan involves drawing $20 million a year from Portland residents, and $20 million a year from Portland businesses. But once administration costs and tax flouters are taken into account, PBOT says it'll be making about $30 million a year.

This wasn't lost on group members this morning, some of whom questioned why the bureau is letting up on the gas. The most stinging criticism came from Vic Rhodes, a committee member who served as director of the then-Office of Transportation back when Hales was transportation commissioner.

"It seems to me that even if you enact this, the whole thing continues to slide backward," said Rhodes, referring to the city's street maintenance backlog. "I’m lost in how this fits contextually."

PBOT staffers say they'll reexamine their revenue goals in coming meetings.

• So where will that $30 million (really a $40 million target) come from? Well, on the residential side, it'll almost certainly be based on how much you make—a stark change from Novick and Hales' initial proposal of making everyone pay a flat fee (with a discounted rate for low-income residents). That was too regressive for many Portlanders, and even Novick frequently groused about it. Then we paid $16,500 to conduct a new poll, and found out that Portlanders might be willing to live with an income tax (something officials had previously said was out of the question). An income-based tax has dominated conversations since.

The revenue bureau has concocted two scenarios. The first is a straight income tax, complying with all the vagaries and complicated nuances of the tax code. Under numbers floated today, households that make $30,000 or less (nearly a third of the city, according to this morning's presenters) would be exempt. It would be capped at $2,400 a year (for incomes nearing $1 million, according to PBOT figures). Here's an example (though you should disregard that $210 figure, which would be capped at $200).

The next option is an income-based tax that snaps people into a set of rigid brackets. This is the revenue bureau's clear preference, because it's easier to administer. There are a lot of uncertainties about this one—proposals exist for capping monthly taxes at $20, $100, and $200 (the lower cap would more evenly distribute the burden, while higher caps would put much of it on richer Portlanders). And again, there would be exemptions based on income and dependents. But rather than working with minute percentages like the tax code, this option puts you in a category based on your income. Examples? Yes, you're right:

This mechanism has a lot of moveable parts that would have to be settled before coming to council. How big should the monthly tax cap be? Who should qualify for exemptions? Would all of the proposals be indexed to inflation? Allowed to lapse after a certain number of years? It's uncertain at this point, but PBOT says it's crafted examples of an income tax that can generate $20 million a year, plus or minus $2 million.

• Which brings us to the business side of the equation—a facet of this morning's presentation that was sending people into Twitter fits about how mind-cracking the schemes are. And this new "Business Entity Flat Fee," or BFF, is complicated. It's just not that complicated.

Basically, PBOT—drawing from workgroup discussion—has created four groups businesses might fit under—based on employees, gross revenue, and square footage (with a fifth group for businesses that hold city business licenses, but aren't located here). Those groups are then divided by broad business categories (agricultural, construction, office, restaurant, and medical are some examples). Figure out what group you belong in, and your business category, and you've got your monthly tax. This time, there's a $120 monthly cap.

There are three proposals along this scheme, with differing distinctions for how the four business groups should look. PBOT drew up an initial plan (again drawing from workgroup discussions), then business owners suggested changes. So did a group concerned with non-profits and low-income earners. They've got subtle differences that I won't go into here, but as an example, here's the original proposal:

The city estimates 120,000 to 125,000 businesses would pay the tax—including 30,000 who don't have locations in Portland. The least a business would pay is $30 a year. The most is $1,440.

At this morning's meeting, work group members had a mixture of sharp questions and appreciative comments over the proposals. Chris Kopca, of the Downtown Development Group, called the vast differences between business and residential tax mechanisms "really awkward,"

"It’s a bad thing to go forward with two formulas that approach it so differently," Kopca said. "I don't think it breeds political goodwill, longterm."

Reservations aside, nothing was decided this morning. More will become clear as the various work groups meet again next week, though even the best-laid plans may not be enough to stop the street fee's most-strident critics from trying to force a public vote. And a lot more, if history is any indication, could change before November.