It is the biggest fish kill in 20 years to hit Charrette Creek.

Some described it as "horrible." Hundreds of fish in a Missouri stream suffocating and dying.

The reason? Someone had released excess sewage into Charrette Creek, just outside of Wright City.

“It's just heartbreaking to see this,” said Denise Maloney, who lives along Charrette Creek and saw the incident over the 4th of July weekend with her husband Rick.

“You know that makes me sick," she said.

“It’s nasty, it’s the stuff you flush down the toilet,” said Missouri Department of Resources Investigator Cole Hough.

It came from a luxury resort community called Innsbrook, which advertises itself as committed to nature, and that it's certified by the Audubon Society as a cooperative sanctuary.

Innsbrook’s CEO Charles Boyce admitted the resort's waste facility was responsible for the spill into the creek.

“We regret that it happened,” Boyce said. “We want to make sure it doesn't happen again.”

He also told 5 On Your Side Investigates that the spill came as a “surprise” because there had been no other violations.

Maria Hallas, Reporter: We've heard there have been minor violations over the course of the years with respect to contaminants in the creek?
Boyce: No.
Hallas: No?
Boyce: No
Hallas: Not even minor violation?
Boyce: I think when you talk to DNR we've got a good record. No, we have an excellent track record.

However, Five On Your Side Investigates uncovered state documents showing that in four years the DNR assessed three separate notices of violation against Innsbrook, all for releasing excess ammonia into Charrette Creek.

“I wouldn't call that a good record considering that he's got multiple years of violations that are publicly documented,” said John Hickey, director of the Missouri Chapter of the Sierra Club.

However, Hickey also said that repeated water contamination violations are common across Missouri.

The reason? He says it's because of lax state enforcement.

“The fundamental problem is the Department of Natural Resources slapped the owner on the wrist, did not require the problem get fixed, and once again we have sewage in the creek,” Hickey said.

We asked Innsbrook for comment about our story and we received a statement from Innsbrook CEO Charles Boyce, saying, in part, "my statements to KSDK on July 18 were true to my knowledge."

But the statement went on to read that after an audit of Innsbrook's records Boyce became "upset and embarrassed to find that there were violations of which I was unaware."

Boyce also says the 'event' has revealed gaps in their processes which they are closing.

Lastly, the CEO adds that Innsbrook is asking for a meeting with the DNR to ensure "the health of the creek."

Here is the complete statement:

Statement from Charlie Boyce, CEO & President:

“My statements to KSDK on July 18 were true to my knowledge at the time. After performing an audit of our treatment facility records, I’m upset and embarrassed to find that there were violations of which I was unaware. These violations had been promptly addressed between DNR and our plant operator, as well as our environmental and engineering firms.

This event has identified some gaps in our processes and we are closing them. We’re requesting a face-to-face meeting with MoDNR, our environmental consulting firm and our engineering firm to find the best solution to ensure the proper function of our facility and the health of the creek.

We’ve been part of the Warren County community for nearly 50 years. Charrette Creek is a treasured part of my childhood memories as well as my children’s and many of our neighbors’. We’re dedicated to giving generations to come the opportunity to make memories there as well.”