Hundreds of people gathered for a special "pillar raising" ceremony on Thursday to mark the one-year anniversary of the deadly gas explosion that rocked Minnehaha Academy in Minneapolis.

It was also the first time since the blast that such a large crowd returned to the heavily damaged high school site that carried painful yet fond memories of the 105-year-old school community.

Many of the 200 people who attended the event came adorned in the school's red and white colors and stood together, singing and praying for a new beginning that would resurrect the private school.

"We have been using the phrase 'Together We Rise' since the tragedy and the first pillar rising from the ground is very symbolic and a very visible indication that we're rebuilding and looking forward," said Minnehaha Academy President Donna Harris, who placed a memorial plaque on the pillar that will be visible from inside the new school.

On Aug. 2, a gas explosion ravaged the upper campus, killing receptionist Ruth Berg, 47, and janitor John F. Carlson, 82. Nine people were also injured, one critically.

Upper School Principal Jason Wenschlag said the tragedy had a significant impact on students, but halfway into the school year the students' emotions began to stabilize.

"We reached a point where kids looked back a lot," Wenschlag said. Now "they are ready to move forward. We tried to respect that and balance that."

Despite the distress students faced, enrollment has remained solid and the school even added some new students, including those from families who were inspired by the community's resilience. There are a growing number of students in every grade level who are interested in joining the school, Harris said.

The new campus will have room for more than 750 middle school and high school students — more than the 350 ninth- through 12th-grade students who are temporarily housed at a former college campus in Mendota Heights. School leaders also are considering moving the middle school campus, which is 1.5 miles south of the north campus, to be near the high school as they prepare for a growing student population.

School officials say they plan to reopen by fall 2019.

In June, the city's planning commission approved the school's project proposal to construct three Scandinavian-inspired buildings on the north campus at 3100 West River Pwky. In preliminary designs, the 100,000-square-foot additions will be connected and have a light fiber-cement paneled exterior with big windows, reflecting the aesthetic of the school's Scandinavian founders. Unlike the previous red brick buildings built in 1913 and 1922, the new additions will face the river. In the footprint of the old building, architects plan to create a grassy courtyard and memorial garden to honor Berg and Carlson.

"The tragedy has caused us to think about re-imagining our school for the future and for the benefit of the kids that we'll attract over the next 100 years," Harris said. "We want to be careful in our facilities planning."

Excavation work at the site began in late June. School officials haven't released a cost estimate for construction but have said the three buildings could be phased in. Kendall Griffith, vice president of Mortenson Construction, said the company worked closely with the design team, the Cuningham Group, to keep costs down.

Minnehaha Academy plans to launch its capital campaign in September and the target amount won't be released until a later date, officials said.

At the pillar raising ceremony, former Minneapolis Mayor Betsy Hodges and current Mayor Jacob Frey spoke to the mournful crowd, encouraging them and also paying tribute to Berg and Carlson. First responders also were applauded for their service during and following the blast.

"I knew I was coming to a tragedy but I didn't know the miracle I was walking to that day," Hodges told the crowd as some, moved by her speech, wiped their tears. "You're the miracle. The building was fragile, your community was not."

Said Frey: "Thank you, Minnehaha Academy. Thank you for fighting a path forward and staying in Minneapolis. You're truly an asset to this city."

Meanwhile, little is known about the gas explosion that damaged the upper campus. The National Transportation Safety Board has opened a probe that could take a year or longer to complete.

A lawsuit filed last fall by relatives of Berg, which put the blame on CenterPoint Energy contractors and Master Mechanical, the Eagan company contracted to move gas meters out of the building, was settled in May.

"We don't have the details," Harris said about the gas explosion. "We're as eager as everyone else to see that report."