PORTLAND, Ore. (PORTLAND TRIBUNE) — TriMet’s general manager says four big projects — only one of them a light-rail line — must be built if the Portland region is to avert traffic gridlock in the next two decades.

Neil McFarlane said it might be considered unusual for the regional transit agency to promote highway projects in addition to the Southwest Corridor line proposed from downtown Portland to Bridgeport Village in Tualatin.

But he told an audience Monday, Feb. 20, at the Washington County Public Affairs Forum that many of the region’s leaders agree.

“There are three big bottlenecks in this region it would be nice to make some progress on,” McFarlane said. “These are projects we’ve known we need to do for some time. They are necessary to keep our region moving and our arterials flowing. But they are very big and expensive projects.”

They are:

• Rose Quarter in Portland, where Interstates 5 and 84 converge, and I-5 narrows from three to two lanes in each direction.

• Highway 217 from Tigard to Cedar Hills, connecting I-5 with U.S. 26 in Washington County.

• I-205, which narrows from three to two lanes in each direction between Stafford Road in West Linn and the George Abernethy Bridge, which spans the Willamette River between West Linn and Oregon City. North of the bridge, I-205 widens back to three lanes.

McFarlane said the Oregon Department of Transportation has begun project development to estimate costs. All are state highways.

He said regional officials await state legislative action this session on a funding package for roads and bridges, transit, bicycle and pedestrian paths — and a share of lottery-backed bonds for the proposed light-rail line. Such state support dates back 25 years, when lottery-backed bonds helped pay for the light-rail line between Portland and Hillsboro.

A joint legislative committee has begun discussions on a framework for aid.

“The state will provide a great foundation for whatever the region would do after that,” McFarlane said.

He also said no single level of government can pay for all of those projects.

Although the state isn’t expected to shoulder the bulk of the costs for such projects, a blue-ribbon panel originally appointed by then-Gov. John Kitzhaber in 2015 released a report last year urging specific relief for metro-area congestion, which affects movement of goods as well as people.

At a meeting with the Portland Tribune/Pamplin Media Group editorial board in January, Senate President Peter Courtney, D-Salem, said he heard a clear message from a number of groups about traffic congestion: “Fix Portland.”

The Portland region is projected to add 400,000 more people by 2040, the equivalent of four cities the size of present-day Hillsboro.

McFarlane said that equally as important are demographic shifts that have resulted in minorities and low-income people — highly dependent on public transit — moving away from central Portland into more affordable housing in the suburbs.

“It means we have to retool the transit system to serve those people well,” he said.

A two-year-old report by the Portland Business Alliance and partners forecasts that motorists will experience 69 hours of traffic congestion by then — almost two full work weeks — but that much can be done to reduce it with spending on key projects.

“I am optimistic we can get this done because we have done it before,” McFarlane said, referring to past efforts to extend light rail elsewhere in the region in conjunction with highway improvements.

“And frankly, I doubt we have much of an alternative.”

Key points in the Southwest Corridor include Oregon Health & Science University in Portland, Portland Community College Sylvania campus, and Tigard. The corridor is the only one of five regional sectors not served by light rail. An environmental review is proceeding.

Its current population is about 240,000, and McFarlane said it is projected to grow by 75,000 — the size of Bend — by 2040.

Only a fraction of them (about 15,000) stay in the corridor for work. According to projections, almost 85,000 come into the area for work daily, and 50,000 leave it daily.

A bus rapid transit system had been proposed for the corridor, but light rail emerged as the preferred alternative because it could accommodate 35,000 riders daily by 2040.

“There’s not a lot of capacity to build new roads — I would say it’s zero capacity,” McFarlane said.

More sidewalks also are envisioned.

The current price tag is $2.4 billion.

McFarlane has worked for the agency for 26 years, and has been its general manager since 2010.

McFarlane said TriMet is not neglecting bus service, and plans upgrades in Washington County, including two new lines. One connects Tualatin Valley Highway with businesses in Sherwood, and the second — to start service within the next year — will connect Southwest Allen Boulevard and Denney Road in Beaverton with points south in Metzger and Tigard.The Portland Tribune is a KOIN media partner.