A City of Ottawa employee has been suspended without pay after allegedly providing incorrect information about a massive sewage spill into the Ottawa River in the summer of 2006.

The information was revealed during an internal city investigation that began last week, said deputy city manager Richard Hewitt in a memo to city council Tuesday.

"It is now my conclusion that the employee who was responsible for reporting the incident to the Ministry of the Environment's spills action centre did not do his job and, in fact, did not make the call," the memo said.

"Furthermore, I am dismayed to inform you that the management was provided with erroneous information by the employee regarding the specifics of when the ministry was initially notified of the spill."

City councillors learned last week about the spillage of 1.2-billion litres of raw sewage into the river, caused when a sewage system valve got stuck open at Keefer Street after a storm in July 2006.

The spill is believed to have led to bacterial contamination at Petrie Island Beach, forcing the city to close the beach's swimming area for 45 days in the summer of 2006.

The Ministry of the Environment has said it is also investigating the spill, and charges could be laid against the city.

On Tuesday, Hewitt said the city was initially told the ministry was alerted to the spill in August 2006. In fact, no official communication with the ministry was documented until May 16, 2007.

Employee could be fired, memo suggests

The employee has been suspended until the completion of the investigation, and the memo notes that "additional disciplinary measures, up to and including termination, may be taken."

At Queen's Park on Tuesday, Environment Minister John Gerretsen faced criticism for not launching an investigation sooner.

Gerretsen said he believed the ministry started investigating as soon as it learned of the incident last year.

"But I stand to be corrected on that," he said.

He agreed that the incident should have been taken seriously.

In the long-term, he added, such incidents should be prevented by separating storm and sanitary sewers so sewage overflows don't happen during storms at all.

Ministry spokesman John Steele confirmed Monday afternoon that the matter has been turned over to the Ontario ministry's investigation and enforcement branch, and that depending on the results, charges could be laid against the City of Ottawa.

"They [investigators] will look at an adverse effect that may have occurred during this time period and the notification to the Ministry of the Environment," Steele said.

Under provincial law, the ministry has two years minus one day to lay charges, meaning any charges would have to be laid before the end of July.

The ministry was officially notified about the spill in May 2007, in a letter sent by Barrie King, the City of Ottawa's program manager of wastewater collection. In the letter, King noted that informal, verbal notification may have taken place earlier.

When asked why the ministry is having another look at the case now, Steele said it was due to the "interest expressed about this matter."

He added that when the spill was originally reported, the ministry was unaware of its impact on public health and public beaches.

Should have investigated earlier: conservation group

Meredith Brown, head of Ottawa Riverkeeper, which aims to protect and promote the ecological health and diversity of the Ottawa River and its tributaries, said she's pleased the ministry is responsive to the public outcry over the spill.

"But a little disappointed that's what it takes to open the investigation, when I think it should have been done the day after the spill," she added.

Brown said the ministry has not been taking enough action against such sewage spills most of the time. The town of Arnprior was fined for a similar spill about four years ago and the town of Hawksbury is currently under investigation for another.

After the 2006 Ottawa spill was discovered — two weeks after the valve became stuck — employees and officials at the sewage plant did not inform other departments in the city, as it was not part of their protocol.

A year later, the city commissioned a costly study to determine the source of bacterial contamination at Petrie Island Beach.

The spill was finally publicized last week after a volunteer group that runs a nature centre on Petrie Island learned about it from an official during a tour of the Robert O. Pickard water treatment plant and informed the media.

The city has since announced that from now on, raw sewage spills must be reported to the city's public health department.

Brown said she wants to ensure that the city's medical officer of health is informed of all spills and is mandated to inform the public.