Correction appended

A state report indicates the Rose Quarter freeway project would likely cost more than $1 billion if proposed covers spanning the interstate are expanded and strengthened to allow for multistory buildings.

That’s one of the takeaways from the Cost to Complete Report released Tuesday by the Department of Transportation. The report also offered the first glimpse at what the various project elements -- like the additional merging lanes or freeway covers -- will likely cost. State lawmakers approved funding for the project, which is on a key stretch of Interstate 5 through inner North and Northeast Portland, in the landmark $5.3 billion transportation package approved in 2017. That law mandated a report on updated project costs be finalized by Feb. 1, 2020. The state is expected to brief lawmakers on the report next month.

The report adds a new wrinkle to the political controversy that is increasingly circling the mega project. While some vocal critics, including some elected officials, have pushed for a more extensive environmental impact statement to study the project’s potential impact on air pollution, traffic congestion and other factors, a separate sticking point has centered on whether the state is doing enough to bridge together the neighborhood that was divided by the freeway decades ago.

The project, which has been in motion for roughly a decade, calls for replacing several existing overpasses spanning I-5 with a freeway cover in two locations. But the state is not currently planning to design those covers to support multistory buildings, instead envisioning two public spaces, which would total roughly two acres.

The Albina Vision Trust, a group that has called for significant changes to the project to help stitch together the neighborhood, has demanded more extensive freeway covers to allow for commercial and housing space atop them. Portland politicians like Commissioner Chloe Eudaly and Metro Council President Lynn Peterson have echoed that sentiment.

According to the 58-page state report released this week, building such covers would drive project costs even higher, and the state said a decision on how to proceed must be made by this summer or the entire project would be delayed.

“Preliminary estimates suggest a range of $200 million to $500 million of additional cost to design and build expanded covers,” the state wrote, “depending on the required length and strength of the covers.”

“Much of the cost is attributed to providing the structural capacity to accommodate the weight of the buildings,” the report states.

Project cost I-5 mainline: $397.8 million to $442.4 million (includes shoulders, auxiliary lanes, retaining walls, traffic signals, pavement, improving some on and off-ramp bridges) Highway covers: $257.3 million to $286 million (includes covers, two new bridges as part of freeway covers, other costs) Local street improvements: $44.2 million to $49.1 million (bike and pedestrian paths, traffic signals, right of way, retaining walls, other costs) Clackamas pedestrian and bicycle crossing: $15.7 million to $17.5 million Total: $715 million to $795 million (Source: ODOT)

The transportation department said the state needs to decide “no later than June” whether to revise the freeway covers to accommodate buildings, or construction would likely not begun by 2023.

Gov. Kate Brown last month called for an independent consultant to examine the freeway cap issue. In May, the state said it planned to hire a consultant. It never did.

In a briefing with The Oregonian Editorial Board and this reporter, the project’s leaders said they still plan to hire that consultant, but they said the state can conduct that analysis on its own and provide details to the Oregon Transportation Commission so it can decide how to proceed.

Megan Channell, the project’s director, said the $200 million to $500 million in additional costs included in the report came from “preliminary estimates” from ODOT employees.

The Cost to Complete report also includes a revised total cost estimate to build the project, which calls for new freeway shoulders in both directions of the Rose Quarter on I-5, merging lanes on a 1.7-mile stretch of freeway between I-84 and I-405, and a number of surface street changes like a new bike and pedestrian bridge spanning I-5.

The project, first estimated to cost $450 million to $500 million, is now expected to cost $715 million to $795 million. That dollar figure is based on 2025 dollars.

The final report’s price tag matches a draft figure first reported by Willamette Week last month.

Project costs rose largely due to inflation. According to the report, the new estimate’s base range includes $130 million in inflation, factoring in a 3% inflation rate. The state also projects it must buy at least $42 million in right of way from adjacent landowners, though no homes will be displaced.

ODOT staff this week again declined to say whether they support moving forward with the project as currently designed or pausing to conduct a more thorough environmental analysis.

But Channell said conducting a full environmental impact statement would add three years to the project timeline. “The need for the project isn’t going away,” she said. Under its current timeline, construction would begin in 2023 and wrap up in 2027.

The report sheds additional light on how difficult the construction could be for the region. ODOT intends to keep “as many open lanes as is possible” on the interstate during construction. But the construction would jam up TriMet and Portland Streetcar service for years.

The streetcar, in particular, would be affected “for approximately two to three years,” with service “switched to a bus bridge” while construction moves forward on demolishing the bridges on Broadway and Weidler spanning the freeway. Roughly 5,000 to 6,000 riders use the streetcar through that area every day.

In a December letter to the state transportation commission, Portland Streetcar Executive Director Dan Bower said a bus shuttle would leave his transit service holding the bag and paying for the added operational costs. “We believe the best solution to minimize disruption and maintain vital transit connectivity during the construction phase is to continue regular streetcar service on temporary tracks over the temporary structures planned for the project,” he wrote.

ODOT says the highway section is the 28th worst bottleneck in the nation, based on the length of its rush hour delays.

Adding the auxiliary travel lanes is a common-sense solution to the weaving issue that leads to rear-end and side-swiping accidents, ODOT says. Some 99% of vehicles that travel southbound after merging onto I-5 from I-405 during evening rush hour commutes are exiting at the Broadway, I-84 and Morrison exits, all of which are inside the project area. “The addition of an auxiliary lane will allow drivers to make these trips without merging into the two through lanes on I-5 before exiting,” the report states.

When asked whether ODOT is considering building the freeway projects like the shoulders and auxiliary lanes first, then dealing with the rest of the project, Channell said that is not the plan at the moment.

“It’s a package right now,” she said.

It’s not clear when the Oregon Transportation Commission will decide the project’s future. The volunteer board, which is appointed by the governor, meets Jan. 23 in Lake Oswego.

Other takeaways from the report:

- Costs are estimated to be at a 70th percentile, meaning planners believe there is a 70% likelihood the final costs will either be within or less than the estimated range.

- ODOT says costs to build retaining walls and sound walls near Harriet Tubman Middle School also contributed to escalating costs. Channell said the state knows more about the topography of the area than it did in 2017, and more dirt needs to be extracted to build retaining walls, and that dirt is contaminated, adding to project costs.

- The overpass bridge known as the Hancock-Dixon Bridge, which is expected to replace the existing Flint Street bridge, has been revised a bit to limit what had been a steep 10% grade. The revisions added some costs and put the bridge at a 7% grade.

Correction: A previous version of this story had the incorrect date for the Oregon Transportation Commission’s upcoming meeting. It’s Jan. 23, not Jan. 26.

-- Andrew Theen; atheen@oregonian.com; 503-294-4026; @andrewtheen

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