I rode the MAX to the end of the line in Hillsboro last night, departing on foot into a vast empty parking lot between a post office and a Taco Del Mar. OPB and Pamplin newspapers chose this scenic location, the Hillsboro Civic Center, to host a debate between Portland Mayor Sam Adams and Washington County Commission Chair Tom Brian on a touchy subject: should the Portland region build up (dense) or out (sprawl)?

The issue "up or out" is the most comprehensible way to understand the immensely wonky and complex process surrounding the redrawing of our Urban Growth Boundary. Adams and Brian are on opposite ends of the spectrum on whether building dense or sprawling out is good for the region and toward the end of the night, I noticed a lot of the pairs' sentences began, "With all due respect..." which, as we all know, is the red flag phrase signaling you're about to very politely call someone an idiot.

A reporter from the Forest Grove News Times asked Adams, rather tongue-in-cheek, whether Portland would benefit from having Hillsboro turning into a sprawling Bellevue-like suburb. After all, it would bring more Christmas shoppers into downtown.

"No," replied Adams frankly. "We don’t have to. Better land use, more effective land use, I support that." Adams says developers should build first on the 15,000 acres of vacant land already within the UGB—that's acreage roughly the size of Manhattan. "Between what’s already vacant and what’s buildable, we don’t have to expand like it’s been proposed."

Pro-expansion Tom Brian argued the progressive angle on sprawl, saying that expanding the development borders would allow for more affordable housing. "We’ve got to be careful as we demolish old structures and create a scarcity of land, real estate values go up," said Brian.

Washington County started out the Urban Growth Boundary (UGB) process wanting to add 34,000 acres of urban reserves, or land slated for future development, to the current boundaries. Environmental and political pressure has whittled that request down to 13,000 acres. Smart hagglers: start high to get what you want.

The hottly-debated map of the urban and rural reserves is now in "preliminary final draft" phase (i.e. "waffly waffle political compromise endgame" phase). The four county representatives are under pressure from developers to open up more land outside the UGB to possible development—which boosts land values, too.

"I get lobbied by developers to bring land into the urban reserve. I don’t get lobbied by a lot of farmers to bring land in. I think that speaks for itself," said Adams last night.

As for his thoughts on the current UGB plan, which keeps the urban growth boundary line firm for now, but adds 29,000 acres of urban reserves regionwide: "We’re a long ways from anything I can support," says Adams. Too bad it's not up to him— Multnomah County Commissioner Jeff Cogen is the local vote on the plan and at last count he "seemed pleased" with the plan.

Check out video of the debate on BlueOregon and the whole damn hour-long audio on Think Out Loud.