Decaying algae cause odour, taste issues

It’s smelly but safe to drink and use.

Water coming from Lake Ontario has had a musty, earthy smell and taste for the past few days.

However, it’s not harmful, just distasteful, said Greg Lymer, the manager of technical support for Durham Region.

“It’s a dusty, musty, earthy smell,” he stated. “It’s safe to drink and to clean in.”

The odour is “affecting all the surface water plants on Lake Ontario,” he noted.

It’s caused when algae dies off, releasing Geosmin and MIB, which are both naturally occurring.

“We expect a few complaints. We haven’t had any for a couple of years. We generally get a few every year,” Mr. Lymer stated. “Normally, we see it when the water temperature changes in mid to late October,” he said.

It depends on the air temperature affecting the temperature in the lake, he added.

The levels of the Geosmin-a and MIB are in the parts-per-trillion range, he noted.

“It’s right at the detection levels.”

In a press release, the Region noted the water has been laboratory tested and found to meet all Ontario Drinking Water Quality Management Standards.

To reduce taste and odour, residents can refrigerate a jug of water or add ice cubes and a few drops of lemon juice in the water.

As the water temperature in the lake drops, the taste and odour issues will disappear.

For more information, call the Regional works department, technical support division, at 905-668-4113, ext. 3488, or toll-free at 1-800-372-1102.

Water quality reports are also available on-line at www.durham.ca.