Tucked away in Portland’s West Hills beneath the International Rose Test Garden, two reservoirs for more than a century sat quietly at Washington Park. That is now changing.

The two reservoirs, operated by the Portland Water Bureau, have provided water to residents since 1894. But one is being replaced and the other is being taken offline. The challenge for the project team is that a gravity-fed system that allowed efficient operations also placed the reservoirs in the path of an ancient landslide. And that means construction of a new reservoir is complicated.

“It’s nice to build reservoirs in gullies and ravines because then you only have to dam one side, so it’s a nice place for water storage,” said Thomas Gilman, an engineer with the Portland Water Bureau. “What geologically existed here was a stream, and the landslide would move and block the stream and the water would come and wash the soil out and it would move again. When they started construction in 1894 the landslide hadn’t moved; it had filled in and was in the process of being washed out.”

Excavation for the original project, however, reactivated the landslide and forced engineers to come up with a solution on the spot. A series of dewatering tunnels bored into the hillside did the trick. The slide was slowed to a geological crawl and the reservoirs went on to serve without incident for many years.

When crews began construction in 2016 on a replacement reservoir, however, that slide once again had to be taken into consideration. Building at a new location was considered and rejected for a variety of reasons, said Teresa Elliott, the chief engineer for the water bureau.

“We would still have had to do something about the slide because it has to have weight on it,” she said. “And all of our infrastructure goes through here, so if we built somewhere else we would have had to build new infrastructure, new piping and everything to get there.”

In the end the estimated $190 million project to replace the two old open-air reservoirs with a new 12.4-million-gallon underground reservoir got started in 2016 with excavation and site work as well as construction of a massive temporary shoring wall on the east side of the site.

Reservoir 4 on the south side was also disconnected from the water supply infrastructure, excavated and used to hold earth excavated from Reservoir 3. It will also support a future decorative reflecting pool.

There is an eight-year timeline for construction of the new reservoir. Work started in 2016 and now has progressed to the point where crews from general contractor Hoffman Construction, Western Rebar and other subcontractors are now roughly 40 percent of the way finished pouring slab-on-grade sections for the four-foot-thick floor of the reservoir. Other crews are now busy constructing massive steel wall forms for the equally thick south walls.

A total of 176 shafts were drilled into bedrock to anchor the reservoir structure into the hillside. On the site’s west side, a new concrete, mechanically stabilized earth (MSE) wall has been constructed to anchor the toe of the landslide.

“This project has caused it to move faster than it had been,” Gilman said. “But it’s still well within our criteria for what is allowable.”

A second tower crane with a luffing jib has been erected at the north end of the construction site and will supplement the first crane operating at the south end of Reservoir 3.

“It took about two years to get to the point where they could start building the concrete structure itself after all the shoring, walls and the shafts,” Gilman said.

“We’re now working on the end walls, and that’s what you’ll see,” Elliott added.

Two historic gatehouse structures fronting the old reservoirs are being refurbished in order to house control valves for the new reservoir.

“The gatehouse is one of those things they wanted us to preserve,” Gilman said. “So we gutted it out and brought it up to seismic standards.”

Construction of the new reservoir is scheduled to be completed by early 2020; then two years will be allowed for the soils to settle and the massive concrete vault to do the same. Crews will then return to the site to build the decorative reflecting pools atop the old reservoir footprints, along with a new grand staircase and other features. Completion is expected in 2024.

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Portland’s largest single-building affordable housing project in 50 years is rising quickly in Lloyd, where it is sure to stand out.

Designed by Lever Architecture and LRS Architects, the 12-story, 240-unit Grand Avenue Apartments (also known as ) project is owned by Home Forward. Crews broke ground late last year and are expected to finish by October 2019. And as the city continues to suffer a serious housing crunch, the building will provide low-income inner eastside residents with the most new affordable units since the 286-unit Hollywood East building opened in 1969.

Oregon’s tax code led Home Forward to devote the entire project to affordable housing.

“When we first conceptualized this building we thought we would likely develop a mixed-income building, and we could not make it pencil,” Home Forward senior project manager Julie Livingston said. “And the thing about affordable housing units is they do not pay property taxes.”

That, she said, is “a huge benefit to the operations budget.”

The decision to designate all units affordable “in no way changed what the building looks like,” said Jonathan Trutt, director of development and community services for Home Forward. “It didn’t change the interiors at all, but it changed the rents we were going to charge.”

217 units in the building will be reserved for households with incomes at or below 60 percent of median family income, and 23 will be reserved for households with incomes at or below 50 percent of median family income. Of the latter units, 20 will be assigned Section 8 project-based vouchers to assist with rental subsidy for individuals recovering from domestic violence. Service partners include the Multnomah County Domestic and Sexual Violence Coordination Office (DSVCO), the Gateway Center, Raphael House and YWCA.

Plans call for 88 studios, 109 one-bedroom units and 43 two-bedroom units in the building, which is rising on the western half of a block bound by Northeast Grand and Sixth avenues, and Hassalo and Holladay streets. The property has seen three previous development proposals fail – most recently a bid in 2012 to build a 28-story, 321-foot-tall hotel.

The current $74 million project is being funded through a mix of public and private sources – primarily $28.7 million worth of federal low-income housing tax credits. An additional $18 million is coming from bond funding, and $5.1 million more is coming from the city of Portland.

The project is being constructed by O’Neill-Walsh Community Builders, a formal partnership between two general contracting firms. The partnership allows O’Neill, a registered MWESB (minority-owned, woman-owned or emerging small business) contractor, to gain experience on larger projects that also require the general contractor to employ certain percentages of minority and female tradespeople.

“We have a long history of really enriching the pool for both our subcontractors in the city and working with nonprofits to build these kinds of buildings that are desperately needed in the community,” Walsh project manager Meghan Herteg said recently as she looked out over the concrete deck that will become the building’s second floor. There, workers from RDF Concrete, Western Rebar, Aluma and others prepared the deck for further concrete.

It’s a fairly standard concrete post-tensioned structure, Herteg said, with an exterior skin consisting of sheet metal and thin brick sourced from Mutual Materials of Clackamas.

Look beyond the tower’s appearance, however, and it’s clear that the design aims to accommodate pedestrian traffic and draw residents into Lloyd.

Lever Architecture principal Thomas Robinson said his firm is excited to see the final product and how it serves the district.

“We were really interested in creating a great home for residents that leverages connections with the vibrant local economy,” he said. “It has proximity to transit and it’s close to downtown.”

The ground floor will provide convenience for pedestrians. An open-air courtyard, named Jim Smith Garden in honor of Home Forward’s former board chairman, is designed to draw in people from all directions. That central space will connect with the building’s lobby, commercial spaces – including property management offices – and the building’s north and south sides via covered walkways. Along Grand Avenue, the building’s façade will gently curve away from the sidewalk on either side of the entrance to embrace pedestrians and give them more space.

“If you look at the plan, the corners are day-lit, which is really nice,” Robinson said. “I think the units are going to be really great, so we’re excited about how the building combines retail and outdoor space and the connections to transit. The building creates opportunity both for people and for the city.”

A LEED for Homes gold rating will be pursued for the project.

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