A day after a major diesel spill, residents have been told it is still not safe to drink the tap water in sections of Longueuil, a municipality on Montreal's South Shore with a population of 230,000.

Preliminary tests show small traces of diesel are present in the drinking water, officials said.

“We got preliminary test results and confirm that there is a presence of hydrocarbon. We will continue to keep advisory in effect,” said Longueuil Mayor Caroline St-Hilaire at a news conference late Thursday afternoon.

The ban on tap water applies to Saint-Hubert, Vieux-Longueuil, Boucherville and Saint-Bruno-de-Montarville.

Graphic Longueuil water ban

The four towns issued the advisory late Thursday morning after residents complained their tap water smelled like gas.

Risk of illness very low, health officials say

Public health officials said that even if people ingested the tap water or cooked with it, the chance of anyone getting sick is very low.

“Diesel is a very volatile product that thankfully … dissipates and dissolves very quickly. We can smell it  even at very low doses  but it takes much higher concentrations for someone to get sick from ingesting it,” said Jean Rodrigue, director of public health in the Montérégie.

“Those who are more sensitive may feel side-effects such as nausea, vomiting, headaches or dizziness. Only a small part of the population will feel any side effects — a very, very, very limited number of people.”

More water quality tests are underway to determine when the ban can be lifted.

The city gave out bottled water at several distribution centres in the area Thursday afternoon. Click here for the locations.

At some distribution centres, the shelves were empty. Frustrated residents lined up for almost two hours before any water bottles were delivered.

At least 100 people were waiting at 6255 Maricourt Blvd. in Saint-Hubert at 3 p.m., with no water available.

St-Hilaire said she wants answers from the province.

“I asked the minister, ‘How could it be that in Quebec it takes all this time to get water to our population? I understand there is frustration, and we are trying to give out information as we get it in real time,” she said.

All schools in the affected areas will also receive bottled water by Friday morning.

Advisory enforced ‘as soon as possible’

St-Hilaire responded to criticism that the water consumption ban was put in place too late — one full day after 28,000 litres of diesel spilled into the St. Lawrence River early Wednesday morning.

'Honestly, the minute there was a doubt, we were there' — Caroline St-Hilaire, Longueuil mayor

The day of the spill, St-Hilaire said there was no reason to believe the water was contaminated.

“We can’t give out a ‘Do Not Consume’ advisory without knowing all the facts. We took the decision as soon as possible. Maybe this morning we could have acted faster — when people said they were smelling gas — but it takes more elements than that to make such a decision. Honestly, the minute there was a doubt, we were there,” St-Hilaire said.

Yesterday, the city issued a statement saying the water was safe to drink. It took more than 12 hours for the city to send out the updated advisory.

Some residents and elected officials expressed frustration over the way the city handled the ban.

Louise Bergeron, who lives in St-Hubert, bought two 28-bottle cases of water at a local grocery store after testing out the tap water Thursday morning. 

"When I woke up this morning, the water didn't smell good," Bergeron said. "I said, 'No, I'm not drinking that.' It smelled like paint. I don't understand why the City of Longueuil didn't warn people earlier."

Isabelle Bérubé, St-Bruno's city councillor responsible for the environment, said his municipality heard nothing from Longueuil until 9:30 a.m.

"We read the paper this morning and we found out there was a problem in Longueuil with the water. That was the first signal. There's 26,000 people in St-Bruno drinking the water that comes from Longueuil. I think it would have been normal to get a phone call before we read in the paper there was a problem," Bérubé said.

Ministry launches investigation

The spill was caused by a generator at the Longueuil waste-water treatment plant on Wednesday morning at around 4 a.m.

The Environment Ministry says it was only informed of the situation at 9:30 a.m.

Quebec Environment Minister David Heurtel said the ministry will lead an investigation.

“What explains that delay — that five-hour or five-and-a-half hour delay between the spill actually being first noticed and the call to our emergency services?” Heurtel said, adding that legal action could be a possibility.

“We will investigate this matter fully, thoroughly and once we have all the facts, we will be able to draw some conclusions, and if there are some consequences, legal or otherwise, we will implement them," he said.

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