NIAGARA FALLS, NY - According to the Niagara Falls Water Board, its Wastewater Treatment Plant on Buffalo Avenue filters an average of 23 million gallons a day of combined sewage, both storm sewage from rain and runoff, and sanitary sewage from toilets and such, before it is discharged into the Niagara River after being cleansed.

It has a capacity of up to 60 million gallons a day.

However, on days when that capacity is exceeded, particularly when there are heavy rains, the excess sewage overflow is discharged into waterways, primarily the Niagara River, without being treated.

“Anytime raw sewage or untreated sewage is flowing into local waterways it's a concern for us," said Jill Spisiak Jedlicka, Executive Director of Buffalo Niagara Riverkeeper, an environmental watchdog agency.

But the overflow discharges from the Niagara Falls Wastewater Treatment Plant and others are legal under the plant's operating permits from the state and federal governments.

“We have a regulatory program that allows permitted pollution of our waterways from waste water treatment plants, and that’s just how the regulations have evolved," Jedlicka explained.

And occurrences are not uncommon.

The EPA estimates there are up to 75,000 such sewage overflows across the nation every year.

Then again, it also seems to happen a lot in Niagara Falls.

Data obtained by our news partners at Investigative Post shows from May 2016 to July of this year, there were at least 80 sewer overflows, resulting in the discharge of untreated sewage.

That’s an average of more than one incident per week.

As well, the volume during that time frame was 545 million gallons. That's enough to fill 800 Olympic-sized pools.

“Whenever these are reported, they are investigated,” insisted Ken Lynch, Deputy Commissioner of the New York State Department of Environmental Conservation (DEC), prior to a fact finding tour of the Niagara Falls plant on Wednesday.

Lynch also noted that wastewater treatment plants, particularly those which process both sanitary and storm sewage (as the Niagara Falls plant does) are susceptible to overflow situations during bouts of heavy rain.

A source at the Niagara Falls Water Board, which operates the plant, and who declined to speak on camera due to ongoing investigations, wished to note it has been an unusually rainy year.

And indeed even last summer, when the area was under an extreme drought, and when there were still eight sewage overflows between June and August of 2016, climatic data shows the most significant of those occurred on dates when there were heavy rains.

Meanwhile, the DEC, as part of an overall investigation which began following a discharge on July 29 that turned a portion of the lower river black and was unrelated to a rain driven overflow, is trying to determine if the Niagara falls Wastewater Treatment Plant is functioning as it should.

"We'll look at the history of the plant, both its recent and past determine what's happening here, and whether there is appropriate capacity, and if not, what upgrades are necessary to address the issues," Lynch said.