What constitutes ice-on?   It is hard to know what standards were used in the "old days".   Since 1993, we have employed the following standard for determining what is the lake freeze-up date:  when the entire lake is skimmed over by ice (regardless of thickness) and remains so for the rest of the winter.  In this observation we ignore minor areas that may open up because of warm conditions or winds.   This is more or less the standard that is used by observers in other parts of the country.

Ice-off dates are a little more complicated because the melting process tends to be more gradual.    Again we rely on the standard that is suggested by ice observers elsewhere - when the lake is "substantially" ice-free (90% or more) it is considered melted.  Hence there still may be some floating ice or some wind-driven piles of ice along some shorelines.

Detroit Lake Historical Ice Data

Big Floyd Lake Historical Ice Data



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Upcoming Meetings and Events
20 February 2020
February 2020 Board Meeting
18 March 2020
MAWD Legislative Days at Capital, St. Paul, MN
19 March 2020
MAWD Legislative Days at Capital, St. Paul, MN
24 March 2020
March 2020 Board Meeting- Note date change
16 April 2020
April 2020 Board Meeting

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PRWD in the News

PRWD/MN DNR Zebra Mussel impact study

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Dan Gunderson, MPR News, visited Lake Sallie with Brent Alcott to discuss the success of the…

MnDNR begins ZM pilot project treatment


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Recent Water Levels
Detroit ICE ft
Last Updated: 1/6/2020
Floyd(s) ICE ft
Last Updated: 1/6/2020


Melissa ICE ft
Last Updated: 1/6/2020
Sallie ICE ft
Last Updated: 1/6/2020

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