The $2-million project is expected to be dedicated later this summer. It underwent significant redesign two years ago at the request of families of the victims. The design and construction team worked around a spaghetti of underground utilities, as well as vehicular and pedestrian traffic above.

The memorials mark the spots where,  more than four hours into the race, two bombs exploded 12 seconds and 210 yards apart, killing three spectators immediately, wounding 264 others and traumatizing many more. Granite pillars of varying sizes, sourced from locations connected to the victims, will stand where each of them died. One police officer who died from injuries suffered in the attacks and another shot dead by one of the attackers days later will be honored by bronze markers in the red brick sidewalk.

The most dramatic elements of the monuments are the four twisting, hollow bronze spires ranging from 17 to 21 ft tall at each location. The cores of the spires are filled with custom-cast glass lights. Eduardo says the spires protect the fragile glass lights, “symbolizing how we protect our ideas in Boston; or who we are.”

Shortly after city officials and the victims’ family members selected Eduardo to design the markers in April 2017, Eduardo hired Stantec to provide engineering and other services. Eduardo and Stantec brought the original design drawings to approximately 50% completion when the families and the city asked that “we consider other options,” says Robert Corning, Stantec senior principal and landscape architect. The families felt the original design, including an up-to-30-ft-tall curving granite marker with bronze detailing, made “too big of a statement,” Corning says. The families preferred a more “low key” design in scale with the street’s existing trees and lighting.

The redesign prevented the team from finishing last year before the fifth anniversary of the attack. “We know that this project is forever, and we want to get it right,” says Patrick Brophy, the city’s chief of operations.

Although the light columns at each site only weigh about 1,200 lbs. each, Stantec’s geotechnical engineers designed robust piles for the foundations due to poor soil conditions. Performing pile work at cost, Norwalk, Conn.-based Conte Co. LLC drove two 37-ft-deep piles at the site closest to the finish line and two 26-ft-deep piles at the second site. Each pile has 27⁄8-in.-dia pipe shafts with three helices measuring 8, 10 and 12 in. “Even though there’s not a huge load, we didn’t want them moving around,” Corning said.

But after joining the project team last fall, Boston-based contractor McCourt Construction determined that the foundation designs had to be tweaked because drawings of record didn’t exactly match existing utility conditions, says Matt McCourt, vice president. The team redesigned the foundations to account for actual utility locations.

McCourt credits the mayor’s office with cutting red tape to ease the way for the work on one of Boston’s most heavily trafficked streets. He says it’s crucial to get the project right for the families, the city “and for all those affected by the events six years ago.” He adds, “although this project is the smallest one our company will complete this year, it is by far the most important.”

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