The Ministry of Environment's review of water samples taken July 2 to July 9, 2015 at the Likely Bridge and Cariboo River locations showed they fell within allowable drinking water standards.
At the Gravelle Ferry Bridge site there were the following exceedances of the BC MOE Drinking Water (DW) Guidelines. Turbidity (for raw untreated water) all dates, and total aluminum and total iron on June 9, 2015.
"Prior to the breach, water samples collected from the Quesnel River at the Gravelle Ferry Bridge had elevated turbidity, total aluminum and iron results," noted the MOE report which was dated July 21, 2015.
"It was thought that the Cariboo River may be a source of turbidity to the Quesnel River as noted downstream at the Gravelle Ferry site, but the samples taken during this past month indicate that both Quesnel Lake (as represented by the Quesnel River at Likely Bridge site) and the Cariboo River have very low turbidity."
Health Canada indicates there is no weight of evidence for adverse health effects of aluminum at levels above the guideline, the report noted, adding the iron drinking water guideline is based on staining and taste, not direct health effects.
"While chemical parameters may not be of concern, residents should still follow Health Canada protocols for treating raw drinking water," the report suggested.