ITHACA, N.Y. — An estimated 0.5 to 1 million gallons of sewage spilled into the Cayuga Lake inlet over the last five weeks as a result of a malfunctioning underwater pipe that went unfixed for weeks.

A crew of recreational boaters discovered the overflow at the inlet earlier this week, triggering renewed inspection efforts by city and state officials.

The problem was fixed within hours after it was reported. But officials believe the sewage had been streaming into the lake for about five weeks before it was found, according to Scott Gibson, environmental engineer for the city of Ithaca.

The .5 to 1 million number is a guess based off an estimate that about 14,000 gallons of sewage were flowing into the lake every day from Sept. 19 until Tuesday, Gibson said.

The leak was caused by "blockage" in the pipes beneath the Siphon Station on the city's west end.

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5 takeaways from sewage problem

Here are five things we learned about the discovered sewage on the inlet:

1 — How serious is this? | Gibson characterized the amount of spillage as serious but not unprecedented or a cause for alarm.

"There's always a concern for the safety of the lake," Gibson said, "But it's not an imminent public health threat."

"The sewage that's there is typically degraded, environmentally; it's not the nicest thing to look at or to see. But there's not a whole lot you can do after the fact."

While city officials are monitoring the situation, Gibson said that this kind of sewage overflow is not particularly out of the ordinary. He noted that a similar overflow occurred in the same area in 2009.

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"Though the severity seems pretty intense, it's pretty typical of this type of flow," he said.

Gibson stressed that the numbers he gave were estimates and not confirmed.

"We have no idea how many gallons went out," Gibson said.

2 — Should the overflow have been spotted earlier? | Gibson said city officials responded as quickly as they could and are tasked with overseeing an 85-mile long pipeline that's very difficult to constantly track.

"The public sits there and says, 'How come you didn't know about that?' But it's an 85 mile collection system: It's impossible to monitor all of it at once," he said. "Once it's reported, we react quickly and that's all we can do."

Given the length of the pipe, Gibson said, it's not surprising that a malfunction — especially one in a part of the city that doesn't see much boat traffic or any pedestrian traffic — could take as long as 5 weeks to be noticed.

"Picture what 85 miles of roadway look like," he said. "And we only have a handful of guys maintaining the system."

3 — 'Odor complaint' triggers city response | The local boating team called the city with an "odor complaint" at 2 p.m. on Tuesday.

City crews cleared the blockage in the pipe and had it working normally again by 3:30 p.m.

The sewage was found near the City of Ithaca's Siphon Station, which is located near Floral Avenue on the west side of the city.

More specifically, the problem stemmed from blockage to a "large diameter pipe" that takes sewage east across the inlet to the Wastewater Treatment Facility.

4 — Increased inspections | Before this incident, city crews only checked the Siphon Station for pipe blockage on a "bi-monthly" cycle, according to Gibson.

Now, they will be conducting inspections every week.

"(Crews) will be monitoring the chamber and the pipe and make sure the wastewater is flowing adequately," Gibson said. "If they see there's a restriction, they'll open it up."

5 — Working with the state | New York state officials are involved in ensuring that the city properly documents the sewage discharge and responds appropriately.

Gibson is currently in the process of filing a report for a state engineer outlining the city's reaction to the overflow problem.