Boiling notices … unnecessary against manganese

Customers of certain abandoned private aqueducts which were under the supervision of Quebec have something to eyebrow by opening their taps. The water that comes out contains a little boring black sand: manganese, a potentially neurotoxic metal. This is the case in a network in Sainte-Anne-des-Plaines, where the boiling notice in force does not change the problem absolutely.

“People have access to drinking water at a terminal-font,” says Émilie Lepage, director of communications for the city.

Met on site, Lucie Dupuis comes to collect water every two days. “I bought four cans,” said the resident of the rue de la Bretagne. When two of them are empty, I will fill them. »»

Even if it does not drink tap water, Lucie Dupuis spent hundreds of dollars to install filters that remove the bulk of manganese. “Before, it was disgusting,” she says. You took your shower and the first water came out black! »»

The city has measured almost three times too much of this metal compared to the standard, during a test in May in the aqueduct of the Normandy estate, where Lucie Dupuis live and 270 other people.

Manganese, which could affect the neurological development of children, is naturally present in the soil and sneaks into poorly filtered well waters, especially when the pressure is insufficient.

The municipality recommends that residents of the field to minimize their consumption of this water and not to use it for baby bottles, even after having boiled it.

Sainte-Anne-des-Plaines also detects repeated total coliforms in the network. These bacteria indicate that adjustments are necessary in the system.

Abandoned aqueducts

Public aqueducts or individual wells serve most Quebecers, but for tens of thousands of them, water comes from small private systems. Often several decades old, they are generally the work of promoters who have offered this service after the resale of their lots, in small urbanized sectors.

The entrepreneur Serge Scire, owner of Aqua-Gestion, has bought around twenty of these facilities over the years. The press reported in April how he simply ceased to take care of his pipes and wells, since he has an incurable cancer. In March, the Minister of the Environment therefore ordered the 12 municipalities concerned to “temporarily” operate its private aqueducts, which provide more or less potable water to 2,500 people in the Laurentians and in Rigaud.

Two and a half months later, almost half of these networks are still under a notice to boil the water before consuming it. However, the measurement remains useless against manganese, which will be even more concentrated after boiling.

The work necessary to resolve the manganese problem in the Normandy domain “would involve significant investments”, recognizes the director of communications of the Ministry of the Environment, Frédéric Fournier. “As it is a provisional exploitation, the ministry does not ask the municipality to trigger these approaches,” he said. Sainte-Anne-des-Plaines must operate the network, not rebuild it.

Manganese confirmed in Saint-Sauveur

Saint-Sauveur is struggling with the same problem in the Sans-Souci sector, where water darkens after breakdowns in certain houses, revealed The press in April.

This is the case with Steve Raut, who collected the black residue at the exit of his tap before driving it. The press had it analyzed in an approved laboratory: it contains 41 % manganese.

“When it happens, the toilet, the bath is black,” said the father, met on the spot. It lasts two, three days, then it comes back to normal. »»

For all affected networks, the environment says it is working with the Public Health Department to establish health risks.

But residents wonder why Quebec is only interested in the question today, because many of them have lived with this black water problem for years.

The Ministry of the Environment does not hold any analysis of the rate of this metal in the water in the Sans-Souci sector. “There has never been a test for manganese on networks,” deplores the director of genius of Saint-Sauveur, Sébastien Bouchard.

The analyzes have been compulsory since last year, if the operator of a network suspects that his water exceeds the standard.

Water that stains in Saint-Colomban

In Saint-Colomban, the Châtelet sector is also served by the company of Serge Scrière, Aqua-Gestion. On site, a resident repeatedly complained to the company for a black water problem, without result.

“I always see small grains in the bottom of the sink. When I see in the morning that the water flows a little black, I do not wash, ”says Nicole Chartrand, who says she has stained several brewed clothes.

Aqua-Gestion did not detect any exceeding from the standard during tests in the summer of 2024. Nicole Chartrand stresses that the problem is intermittent, and that no sample was taken when its water was black. She documents in video the episodes of black water that occur at home.

These manganese residues accumulate especially during pump problems which decrease the pressure in the network. To bring the contaminants out, the aqueducts must carry out “rinsing”, but Saint-Colomban has never found a valve to do it in the networks of the scrian serge.

“It’s not on the plans,” said communications director Émilie Sénécal. It is suspected that there was never any. »»

Manganese: a new standard, and a more disturbing study

Manganese has been the subject of a standard not to be exceeded in drinking water only since June 2024.

In too large quantities, it could have neurotoxic effects, which are still poorly understood, according to the National Institute of Public Health of Quebec.

The government recommends avoiding consuming water exceeding the standard of 0.12 mg/l and avoiding giving babies under 1 year.

However, a Quebec study of 2011 also mentions significant risks in older children. Published in the journal Environmental Health Perspectives From the National Institute of Environmental Health Sciences in the United States, it establishes a link between water consumption containing a lot of manganese and a lower intellectual quotient, in 362 children from 6 to 13 years old.

“For those who consume it chronically, there would be a risk,” said the professor in environmental epidemiology who piloted the study, Maryse Bouchard, today at the National Institute of Scientific Research.

However, public health has not chosen to publish more strict recommendations targeting older children.