Here's about the best information I could find. The page I've copied below has links that would have taken me to city documents, but each of the links attached to city documents are 'no longer available'. All of the newspaper articles are in the archive section, the Washington Post story might be worth the purchase, but I still don't think any of the initial renderings are available.
I-405 Cap:
Architects look at Katz’s idea of developing I-405 airspace Oregonian, 5.15.98
Idea of I-405 lid unleashes inspiration: A downtown exhibit draws the curious and enthusiastic, plus a smattering of doubters wondering about other priorities Oregonian, 7.3.98
No limits on imagination mayor generates some welcome excitement by seeking unlimited ideas for capping I-405 Oregonian, 7.8.98
Katz proposes to bridge Portland’s gap: Portlanders were asked to participate in changing the landscape of the I-405 Vanguard, 7.8.98
The new urban frontier Washington Post, 7.15.98
Most opt for park on I-405 freeway cap during public debut Daily Journal of Commerce, 7.27.98
Dream ahead to 2023—live, work, play atop 405 Oregonian, 10.5.98
Volunteers present City Council with I-405 ‘capping’ report Oregonian, 11.19.98
Katz appoints team to study how to cap I-405 Oregonian, 4.5.99
Portland caps: Series of concrete lids over a Portland freeway could create new land for development in a city fast running out of downtown space Urban Land, 7.1.99
"As for West End-Lower Goose Hollow, it has a huge potential. It is between downtown and Northwest Portland, with light rail running through it, a new park block nearby, easy freeway access, and soon a streetcar to run on 10th and 11th Avenues. In the 1970s, we cut a massive swath through 12 blocks of this neighborhood to build I-405. It was a thriving and prosperous neighborhood of schools, religious institutions, businesses and bookstores near the library. Normally, I would not advocate that we cover up our mistakes, but in this case I would make an exception. I propose that we cover sections of I-405 and bring back a great neighborhood. Above I-405, and in the neighborhoods surrounding it, we have the potential to build parks, design an urban high tech campus, provide parking, create pedestrian walks, build housing, office and retail space. There is no question, this will be a challenging project, but also very exciting for the future of the city. Again, both the Rose Quarter and West End/Lower Goose Hollow projects, along with the River District and North Macadam will relieve the pressure to build more housing in single family neighborhoods." Vera Katz, State of the City address, 1.22.98
"The ‘Bridge the Divide and Cap I-405’ effort is a way for us to reconnect neighborhoods and to reclaim the land for better use. It is a way to capture elements that are Portland. It is a catalyst for the development of adjacent blocks that have languished for the last 30 years because of the freeway. Today, thanks to the American Society of Landscape Architects and the Landscape Architecture Foundation, and nearly one thousand citizens who participated in this visioning process, we now have some great ideas of how to reclaim some of the valuable neighborhoods lost during the construction of the I-405 ditch." Vera Katz, I-405 Vision Study Announcement, 10.15.98
"’Anything you want to envision has been done somewhere,’ said Paul Morris, whose team has been researching success stories from other cities." Business Journal, 6.26.98
"Mayor Vera Katz has brought new energy to an old idea last talked about in the 1986 Central City Plan. Back then, unlike many other visionary parts of the plan, the idea didn’t generate much serious interest." Oregonian, 7.8.98
"To have any hope that the central city will absorb the job and population growth earmarked in the Region 2040 forecast, we’re gonna need some land." Randy Gragg, Oregonian, 10.11.98
"Katz says capping the interstate also would help reduce growth pressures in other neighborhoods. The city is trying to add 70,704 homes by 2017 to help reduce sprawl in the region." Oregonian, 4.5.99
"Last year, nearly 1,000 people enthusiastically offered up ideas to capture more of Portland’s growth in the central city, reconnect neighborhoods and make better use of vacant air space by capping the I-405 freeway." Vera Katz, Oregonian, 5.12.99
In Portland's 1988 Central City Plan [I-405 CCP.doc], city planners first identified building on top of I-405 as a future vision for the city. Ten years later in the 1998 State of the City speech, challenged the citizens of Portland to revive that vision and think creatively about what could be built above I-405 to bridge the neighborhood divide created by the construction of I-405. Capping the freeway will provide Portland with an opportunity to protect more growth impacts on existing neighborhoods and help protect the Urban Growth Boundary by focusing more growth in the downtown area.
With the American Society of Landscape Architects and over 1000 neighborhood and expert volunteers, created a detailed vision strategy that calls for capping 26 blocks of I-405 to create space for 2,000 new jobs, 2,600 new housing units, 1,300 parking spaces, six acres of parks, retail and entertainment space. A strategy team composed of developers, city and state transportation staff, neighborhood representatives and interested citizens are currently developing an implementation strategy. Their report is due early 2000.
Mayor's Economic Development liaison:
Linly Rees
Office of the Mayor
1221 SW Fourth Ave., Suite 340
Portland, OR 97204-1995
direct line: (503) 823-4277
e-mail:
lrees@ci.portland.or.us
http://www.ci.portland.or.us/mayorstate/I.htm