Caleb Schwab, 10, died on the Verrückt water slide at Schlitterbahn Kansas City water park on Sunday

Credit: Travel Channel

The 168-foot Kansas City water slide where a 10-year-old boy died on Sunday was repeatedly delayed from opening in 2014 due to glitches – including one issue that caused water rafts to fly off the slide and into the air, prompting a slew of additional safety precautions, according to a documentary about the building of the amusement ride.

Investigators are working to uncover exactly what happened to Caleb Schwab, the 10-year-old son of Kansas lawmaker Scott Schwab, on the 17-story Verrückt water slide at Kansas City’s Schlitterbahn water park.

In an episode chronicling the ride’s construction and opening on the Travel Channel’s Xtreme Waterparks, rafts were seen flying off a test model of the slide – which was half the size of the finished ride.

During early testing of the ride, even rafts holding sandbag occupants were launched off the slide at a section called the “Hill,” an at least 5-story high point where riders are weightless, USA Today reported then.

“We had many issues on the engineering side,” Jeff Henry, Verrückt creator and Schlitterbahn co-owner, told USA Today at the time.

“A lot of our math was based on roller coasters at first, and that didn’t translate to a water slide like this. No one had ever done anything like this before.”

To remedy the flying raft issue, officials added an extra five feet to the already 55-foot hill and reduced the ride’s slope to decrease speed. Additional safety precautions added include a net enclosing the chute to retain the raft, velcro seatbelts and weight restrictions.

Half of the slide was torn down with corrections costing $1 million, USA Today reports.

Schlitterbahn officials did not immediately respond to requests for comment from PEOPLE, but officials released a statement on the park’s website.

“We are saddened to share that a young boy died on Verrückt this afternoon,” the statement reads. “Given that safety is our first priority, we have closed the Kansas City park today and Monday and have closed the ride pending a full investigation. Our thoughts and prayers are with the family during this difficult time.”

“We Honestly Don’t Know What’s Happened”

Schwab was with his family at the park during an event for elected officials when tragedy struck.

The exact circumstances surrounding Caleb’s death are unknown at this time, but a Kansas City, Kansas, Police Department spokesman tells PEOPLE that the boy was “on the ground” when officers arrived at the scene at around 2:30 p.m.

A GoFundMe campaign was started to help the Schwab family cover funeral costs.

“We honestly don’t know what’s happened,” Winter Prosapio, director of communications for Schlitterbahn, told reporters, according to The Kansas City Star. “That’s why a full investigation is necessary … To be honest, this is not something we’ve experienced.”

Prosapio said that the park’s rides are inspected daily by an “outside party,” the Associated Press reports.

“It’s a Safe Dangerous Now”

The ride was set to open in May 2014 but didn’t start taking riders until July, according to KMBC 9.

Henry, the ride’s creator, praised the ride ahead of its opening and warned that Verrückt isn’t a “family ride.”

“It’s dangerous, but it’s a safe dangerous now,” Henry told USA Today. “Schlitterbahn is a family water park, but this isn’t a family ride. It’s for the thrill seekers of the world, people into extreme adventure.”

The Verrückt (German for “crazy” or “insane”) was named the world’s tallest water slide by Guinness World Records in 2014. Riders, required to be at least 54 inches tall go down the slide in multi-person rafts that hold up to 550 pounds, according to the Star.

Riders climb 264 stairs to the top – there are call boxes along the way for emergencies – and the rafts hit speeds of up to 70 mph, the Star reports.

Henry and another man were the first people to test the ride, and he joked to USA Today then that he was “still recovering mentally.”

“It’s like jumping off the Empire State Building,” he said. “It’s the scariest thing I’ve done.”