The province has charged the City of Hamilton in connection with a leak that saw 24 billion litres of sewage and stormwater enter Chedoke Creek over four years.

The two alleged offences were identified through an investigation by the Ministry of Environment, Conservation and Parks (MECP).

A court summons dated Dec. 8, 2020 outlines the charges, which are both linked to causing or permitting raw sewage to be discharged.

The first relates to discharges between July 9 and 31, 2018 and the other from Jan. 29, 2014 to July 18, 2018.

Councillors were notified this week that the ministry would serve the city, which will review the materials and brief city council and eventually the public, according to an internal email to the mayor and council.

The email also indicates that council has been bracing for this.

"As directed by council on Aug. 10, 2020, external legal counsel will review the charges and the provincial disclosure materials in support of the charges once staff receive them and report back to council as soon as possible," said the memo from city solicitor Nicole Auty, a copy of which was obtained by CBC News.

The city confirmed the charges in a statement released roughly an hour after CBC News sent questions asking for details.

"At this time, the city is reviewing the charges and associated materials received from the MECP," it read, saying more updates would be provided once staff had reviewed the relevant documentation.

"The city has fully cooperated with the MECP's investigation and is invested in achieving the best possible outcomes for Chedoke Creek and Cootes Paradise."

The city faces one charge for an alleged violation of the Environment Protection Act and the other under the Ontario Water Resources Act.

The ministry says it's up to the court to set the amount of any fines the city could face, depending on factors including the type of charges laid and the seriousness of the offence.

Under both the Ontario Water Resources Act and the Environment Protection Act, fine amounts for corporations can be levied for each date an offence was committed, between a minimum of $25,000 and a maximum of $6 million for a first conviction.

The ministry declined to comment further as the matter is before the courts.

The charges are the latest chapter in an already expensive environmental ordeal related to the years-long leak from a combined sewer overflow (CSO) tank.

Starting on Jan. 28, 2014, a gate partially opened on an underground tank at Main and King streets. The city didn't notice it until 2018. By the time it fixed the issue, 24 billion litres had escaped into Chedoke Creek, which flows into Cootes Paradise and eventually Hamilton Harbour.

The ministry ordered the city to hire a consultant. SLR Consulting told council that it's hard to know if any long-term environmental damage was done, but said dredging wouldn't help.

The ministry disagreed last month and issued a new order, saying the city's "do-nothing approach" was unacceptable.

The city is cooperating with the order, although at the time, Mayor Fred Eisenberger disagreed with the ministry's characterization.

"We're not at all in a do-thing approach," he said in November. And the issue of waste getting into area waterways, he said, is a system-wide problem that's "decades-old."

In a Dec. 4 email, spokesperson Jen Recine said the city is interpreting the order now, and will tell the public "as soon as possible" what its next steps are.

The city has feared a charge and subsequent fines. In fact, city councillors said last year that they didn't make the issue public sooner because city lawyers told them behind closed doors that it would make the city more vulnerable to fines.

The memo says the city is working out a plan to communicate with the public about the charges once it knows more about what they entail.

The city is set to appear before the Ontario Court of Justice on Feb. 3, 2021.