During periods of rain as little as two-tenths of an inch, according to Chrissy Reiman of Riverkeeper, the sewers become overburdened and raw sewage is dumped into Flushing Bay.
“The largest CSO in the city is in Flushing Bay,” said Reiman, who serves as NYC Water Quality project coordinator for the group.
She said her group has noticed a link between large numbers of dead fish in Flushing Creek and Flushing Bay and major CSO events, like the one that occurred the week of August 7, when residents began noticing the dead fish.
But a spokesperson for the Department of Environmental Protection (DEP) said the large number of dead bunker fish, or Menhaden, was the result of larger predatory fish.
“Despite the fact that New York Harbor is cleaner today than it has been in more than a century, fish kills such as this are not uncommon as predator fish trap groups of smaller fish in shallow waters until they have exhausted the available oxygen,” the spokesperson wrote in an email. “Reckless charges about the cause of the fish kill that are not based on fact or science do not advance the cause of cleaner waterways.”
He further stated that DEP tested the waters last Monday and oxygen levels were sufficient to support marine life, and that if the water was dangerous to marine life, it would not make sense that only one species of fish died.
He added that the rainfall on Monday night was captured by the $350 million sewer overflow tank located in Flushing Meadows Corona Park, and that no CSO was discharged into the bay or creek.
But James Cervino, a marine immunologist, said the dead fish he inspected didn’t show signs of trauma, a sign that other predatory fish were the culprit. He said it was likely that algae blooms produced by the release of nitrogen-rich raw sewage was to blame.
“It’s the toxins from the algae bloom and the lack of oxygen,” that killed the fish, he said at a press conference last Friday afternoon.
Over the last decade, DEP has invested nearly $500 million in upgrades to infrastructure in the Flushing Creek and Flushing Bay drainage area. The agency has also proposed building a $1 billion sewer overflow retention tunnel for the watershed.
But another proposal has activists alarmed, and that is a plan to chlorinate CSO discharge before it enters the waterways during certain parts of the year. Councilman Peter Koo recently sent a letter to the acting commissioner of DEP urging him to reconsider the plan.
“With rapid development happening in our community, we need more capacity to capture raw sewage,” Koo said last Friday. “Chlorine is what you put in your swimming pool to kill bacteria, not what you put into a tidal estuary full of precious marine life.”
“Chlorination will kill the E. coli, but it will kill every living thing in the bay,” added Cervino.
Remein said while the chlorination may help with the toxicity of the raw sewage, it does nothing to address the debris and other items floating in the sewage.
“It kind of puts a band-aid on the problem,” she said. “The solution is to capture, not chlorinate.”