Issue report


Ontario, Canada

Reported by:
Mike Grinnell

About this Location

Loon Lake : Center Deep Spot

18 Observations
2 Issues


Slowly and consistently increasing chloride levels in the lake. chloride as monitored by the mecp. the lake is bordered on it’s northern perimeter by highway 118e. the highway is on the riparian zone. the municipality, the county, the province, and the federal government has been advised. the mot has advised that it is now using wetted salt and has reduced the amount of salt deposited by 20%. a letter has recently been sent to the premier, doug ford, asking for his help. i will continue to monitor mecp results and will use chloride test strips during the year. chloride level as of 2021 is at 14.0 mg/l and it was 10.40 mg/l in 2015, as per the mecp.


Have you seen this before?

Yearly for the past few years, as per MECP analysis of LPP samples

Have you notified any other agencies?

See above


Current weather What's this?
  • cloudy
Winter snow off and on
Weather in previous 24 hours What's this?
  • cloudy
As above

Issue history

  • 2023-01-08 - 09:37:00

    Other reported to Water Rangers : Explorer's team by Mike Grinnell.

  • 2023-03-03 - 06:56:00 Mike Grinnell commented

    MECP District Office in Peterborough now on board with problem. Received 2022 Chloride level of 12.5 mg/L showing a reduction in chlorides. Will be reviewing further with MECP and also with MTO. Appears that perhaps the wetted salt usage has reduced levels of chlorides. More monitoring definitely required plus lots of dialogue.

  • 2023-03-30 - 13:44:00

    Mike Grinnell has closed this issue.

    MECP has reviewed quite thoroughly and agrees that monitoring by their labs under the Lake Partner program will continue. They also agreed that I continue to work with the MTO in stressing the importance of the MTO following the salt management program and managing their contractor who spreads the salt and is responsible for equipment calibration. This is not an abatement issue but requires working with the MTO to improve any issues. I was asked to keep the MECP updated as necessary and to contact them any time I wanted.

  • 2023-03-30 - 15:23:29 Mike Grinnell commented

    I have also obtained and will be evaluating chloride test strips throughout this season and will report to Water Rangers and their usefulness at the season’s end. Some good news, the MECP told me today that chloride levels are generally coming down across the province.

  • 2024-04-11 - 20:07:29 Mike Grinnell commented

    A 2024 test on April 7, showed a chloride level of 10.83 mg/L. That’s a good reduction and is likely because of the efforts of the MOT at using per-wet salt and checking the calibrations of their contractors spreaders and the slightly warmer and shorter winter season. That amount is slightly less than one half of the +5 to 40 mg/L dangerous level noted in the 2020 study done by members of the MECP, York, and Queens University that cast doubts on the CCME threshold of 120 mg/L. Success !