Cause of fish kill at Bonsal Preserve named

A broken discharge line at the Montclair Beach Club was found to be the cause of an almost complete fish die-off in the portion of the Third River that runs through the Alonzo F. Bonsal Wildlife Preserve.

The New Jersey Department of Environmental Protection issued a notice of violation on May 19 to the Montclair Beach Club for an “unpermitted discharge” from a broken 4-inch, cast iron wastewater discharge line that is suspended above the Third River, DEP Press Officer Larry Hajna said. 

A woman visiting the preserve on May 10 alerted Jonathan Grupper, a member of Friends of the Bonsal Preserve Conservancy, after she saw dead fish on the riverbanks, he said. 

“We had a severe die-off, where what we believe is the entire population of fish in the river just suddenly turned up dead,” Grupper said.   

He called the New Jersey Department of Environmental Protection, which sent an investigator the next day, he said.

The source of contamination remained a mystery for about a week, but volunteers knew by the color of the water, which was clear upstream and white downstream, that it had to be coming from upstream, Grupper said.

“Over the years we've tried really hard to get to know all of the impactors upriver from us so that we can engage them and make sure that they are aware of any kind of impacts they might have,” he said. 

Those upriver include Department of Transportation projects on Route 46, by the river’s headwaters, the Montclair Beach Club and a Newark water treatment facility on Valley Road, Grupper said.

On May 18, a group of volunteers seeking answers was at the right place at the right time, Grupper said. They discovered a pipe “gushing a white, viscous liquid, sewage,” he said. “The discovery was truly a community effort.”

The notice of violation specifically applied to a discharge of wastewater from the pool club that occurred on May 18, Hajna said.

“However, several discharges are believed to have occurred beginning around April 16, resulting in a large fish die-off in the Bonsal Preserve,” Hajna said. “Under normal operations, water from the pool club is discharged into the Clifton sewer system.”

The club’s owner, Jim Grady, told the DEP on May 24 that the pipe has been repaired. Hajna said the DEP will send an inspector to confirm and “will continue to further evaluate the response actions taken and ecological impacts to determine if any further enforcement action is appropriate.”

In an email, DEP public information officer Caryn Shinske said a conservation police officer reported after visiting the site on May 11 that the dead fish included American eel, blacknose dace and white sucker species, and that he saw no live fish in the water. The officer also reported no noticeable turbidity or smell at the time at the scene, she said.

DEP officials did not comment on what contaminants were going into the river that killed the fish.

“The substance infiltrated the water and all the fish died,” Grupper said. “Part of what was really tragic about that was realizing how robust [were the] species of fish that lived in the river. For instance, we didn’t even know about the eel. It’s been endangered.” 

For now, the portion of the river in the preserve will remain without fish, but Grupper is hoping that the healthy fish upstream will begin to repopulate downriver.

“Hopefully it will do what nature does and repopulate itself,” he said.

The Friends of the Bonsal Preserve organization is happy about the DEP’s quick response, Grupper said. 

“We're excited about having their attention and help and their acknowledgment of the urgency,” he said. “It’s gone a long way for us.”

He said he was happy the source had been located and that the pipe had been fixed, adding that the Friends have a good relationship with all surrounding property owners to safeguard the river. 

When looking for the source of the fish kill, the volunteers did not rule out lawn fertilizers.

Grupper said the biggest impacts on the river come from Montclair residents who live along the river and their lawn fertilizers. The fertilizers contain nitrate, which washes off lawns into the river and creates “severe oxygenating events,” he said.

“We would like residents to do a better job of working with their landscapers and making choices that are environmentally friendly,” he said. “If you live near the river, that's your responsibility.”