PUEBLO, Colo. (CBS4) – June marks 100 years since Pueblo endured its most historic and devastating natural disaster: the flood of 1921. The Arkansas River flooded, sending rushing water said to be more than a mile wide and 15 feet deep in some areas into the downtown area. Buildings were destroyed, lumberyards caught fire and many people lost their lives.

To commemorate the 100 year anniversary of this historic event and the recovery thereafter, Rocky Mountain PBS has teamed up with the Pueblo County Commissioners. Photos show the devastation of the flood that even wiped out the railroad system in the town in the southern part of the state.

Justin Bregar, a filmmaker working on a documentary about the flood and redevelopment of Pueblo, said that at that time Pueblo was the industrial hub of Colorado. That’s because any railroad that went anywhere west of Colorado went through the town.

“Economically, it really hit the railroads hard,” Bregar explained on an interview with CBSN Denver. “It hit the business district down there pretty hard. It essentially shut down the city of Pueblo, locked that area off from even relief efforts around it because it washed the bridges out.”

Watch Bregar’s complete 8 minute interview below:

Bregar said this was the start of a tough period of time for Pueblo, as the flood destroyed many families’ livelihoods. Then the Great Depression and Dust Bowl came next.

Years after the flood, recovery and redevelopment was key. It required city, county, state and national aid. The first step was to move the river itself,= to prevent this tragedy from ever happening again. Bregar said the famous Historic Arkansas Riverwalk of Pueblo now stands where the Arkansas River initially was.

“You can walk down Union Avenue — it’s walkable — and to where the Arkansas River is now and see the levees and the recovery efforts,” he said.

Some buildings to this day still have water marks from the flood.

It’s not known how many lives were lost in the disaster, but the estimate is anywhere from the low hundreds to thousands.

Bregar said the railroad was eventually moved due to the disaster, which led to the Moffat Tunnel being built and the State of Colorado’s transportation setup as we know it today.

“It would be interesting to know what it would have been like if it never happened,” Bregar said. “The Moffat Tunnel may never have been built, or may have been built much later had the flood not happened.”

Several events will be held in Pueblo on Wednesday to commemorate the flood and the recovery over the years.

Makenzie O'Keefe