
Angles were built into the Clearwater Building to maximize open space in the tight fit with the U.S. Bank Building. Photo by Pete Grady.
The two-month old Clearwater Building is the “jewel in the crown” in downtown Boise’s City Center Plaza in the eyes of the plaza’s visionary, Tommy Ahlquist.
Ahlquist is chief operating officer of Gardner Company, which owns all three components of City Center Plaza: the U.S. Bank Plaza tower, Eighth and Main, and the Clearwater Building.
U.S. Bank is a 1970s office tower, though undergoing constant modernization. Eight and Main is a 2014 office tower.
But the Clearwater Building is four different worlds in one building: offices for Clearwater Analytics; an academic setting for the Boise State University computer sciences department; convention center meeting space for Boise Centre East; and a bus terminal for Valley Regional Transit.

The 14,000-square-foot ballroom is the main attraction in Boise Centre East, which has a passage into the Clearwater Building on the fourth floor. Photo by Pete Grady.
The $70 million, 383,000-square-foot Clearwater Building was unconventional from the start. Gardner Company bought the 19-story U.S. Bank Plaza specifically for its 1.2-acre surface parking lot. Gardner knew it would fill the lot with an office building, but in October 2013 nothing else was nailed down.
Ahlquist said that at that point, the Boise State computer science department was “probable,” and VRT’s bus terminal was “possible.” He viewed the possibility of the Greater Boise Auditorium District putting Boise Centre east meeting rooms into the Clearwater Building as “a grand slam home run.” Gardner and Clearwater jointly announced the City Center Plaza project in December 2013.
The Clearwater building itself is no basic square or rectangle. Walls splay out at angles and patios on two floors air out the façade.
“It’s three major projects in one on a very challenging site,” said Rob Cottle, principal at Babcock Design Group, Gardner’s Salt Lake City-based architectural firm. “I even wondered if it would work. Each element would have been a significant challenge in itself.”
The challenge centered around fitting an office building, bus terminal and convention center on an L-shaped 1.2-acre parcel squeezed between the U.S. Bank Tower, CenturyLink Arena and Grove Plaza.
Above and below ground abounded with engineering challenges.

Engineering the turning radius for a bus was a challenge for the Main Street Station beneath the Clearwater Building. Photo by Pete Grady.
The north-south-oriented Clearwater Building’s fourth floor is a conjoined twin with the neighboring east-west-oriented Boise Centre East expansion. From the inside, it is a seamless transition from the 14,000-square-foot ballroom in the Boise Centre East structure to the meeting rooms in the Clearwater.
But a deep steel girder system needed to be engineered to bridge the two buildings. Expansion joints that would allow the building to move in an earthquake had to be incorporated into the convention space without being apparent to visitors, Cottle said.

Bicycles dominate at City Center Plaza, which includes the Clearwater Building (left), Eighth and Main (right) and U.S. Bank Plaza (not pictured). Photo by Pete Grady.
Ahlquist dreamed up the bus terminal-in-the-basement idea on a Greek cruise as a solution to the vexing question about what to do with the transit mall on Main and Idaho streets. Then came a long list of potential flaws: the water table, sharing a wall with the existing U.S. Bank parking garage and the foundation for the tower itself, bus ramps, and building a nine-story office building above the bus stop.
Before a building could rise out of the ground, Babcock Design Group had to figure out how to shore up the excavation. The design team also had to fit in the bus entry and exit ramps alongside the U.S. Bank garage and engineer the turning radius for buses beneath the Clearwater Building and portions of Grove Plaza, Cottle said.
“The lid of the VRT (bus terminal) and how it supports Grove Plaza was challenging (because of) how much load it has to carry to match up with Grove Plaza” because the roof or lid of the bus terminal is several feet lower than the plaza, he said. ESI Construction in Meridian was the general contractor.
In the end, though, the Clearwater Building is about what people experience.
Ahlquist went for spray paint art in the main lobby, courtesy of the Boise artist collective, Sector Seventeen, inspired by a visit to FACES of Hope Victim Center.

Spray paint art by Sector Seventeen dominates in the Grove Plaza east spoke tunnel and the Clearwater Building lobby. Photo by Pete Grady.
Later, he turned to Sector Seventeen again to spray paint the huge concrete wall in the tunnel that is now the Grove Plaza east spoke to Capitol Boulevard under the elevated Boise Convention Center East. Their 183-foot-wide mural starts 65 feet high and slopes down to just about a couple feet as that wall supports the ramp for the 68-stall, above-ground garage Gardner wedged into the Boise Centre East structure to replace the spaces from the original surface lot.

Collin Pfeifer (left) and Hawk Sahlein of Sector Seventeen put the finishing touches on the mural in the east spoke of Grove Plaza. Photo by Pete Grady.
Sector Seventeen also provided a mural for Clearwater Analytics.
The walkway between U.S. Bank and Clearwater has a ribbon of blue paint, flowing like a symbolic river from Main Street to Grove Plaza and then alongside the Sector Seventeen mural in the east spoke tunnel. Even the lighting above the tunnel meanders like a river. Decorative fish are embedded in the painted stream at the miner statue between the main entrances to both buildings.
Bikes were also on the mind of Ahlquist and the design team. Bike racks line Main Street. Bike storage will be available on two levels of the garage with the Sector Seventeen mural. There will be bike valet service. The stairs to the Main Street Station bus terminal have bike rails on both sides.
City Center Plaza will have its own bike share program for tenants, starting with eight red bikes.