Ville de Pointe-Claire

Ville de Pointe-Claire

October 17, 2011 13:26 ET

Statement from the City of Pointe-Claire

POINTE-CLAIRE, QC, Oct. 17, 2011 - Results of tests carried out during the week-end of October 14th-16th suggest that an abnormal quantity of ammonium nitrogen, present in the crude water drawn out of Lake St. Louis caused the dramatic reduction in chlorine levels forcing the city to issue two water advisories. 

Generally, the presence of ammonium nitrogen in Lake St. Louis at this time of the year results from decomposition of algae and other organic material. 

Ammonium nitrogen is frequently found in low concentration in Lake St. Louis and is adequately dealt with by our water treatment plant. However, on October 14th, 2011, the City recorded an all-time high in concentration levels, likely exacerbated by unseasonably warm temperatures. 

Following consultation with public health authorities, it was decided to issue an advisory of non-consumption of water for preventative purposes. 

Water quality was eventually stabilized and returned to normal over night Friday with a massive increase of chlorine. On Saturday morning, the non-consumption water advisory was changed to the boil water advisory while the distribution systems were flushed. On Sunday at 6:00 p.m., the advisory was lifted and all returned to normal status. 

The City of Pointe-Claire will consult all the necessary experts regarding this major event and will make every attempt to ensure that this situation does not occur again.

We acknowledge the inconvenience this may have caused residents of the West Island. 

Contact Information

  • City of Pointe-Claire 514 630 1200
    W. McMurchie