Grace Lake Watershed Improvement Association

“It is our mission to improve, preserve, and vigorously protect the quality of our natural resource for the benefit of all who surround and use it.  Through education and implementation of remedial and proactive measures, we will achieve a sustainable balance of flora, fauna, and recreation for ourselves and those who follow us.”

The following is an article done by RMB Labs I thought might be interesting. 

Lake Learning

Fall turnover in our lakes

The temperature has cooled lately and the wind has picked up. These are the ingredients needed
for fall turnover in our lakes. A couple months ago I wrote about how the lakes separated into
layers in the summer, which is called stratification. To recap, the layering of lakes has to do with
the relationship between water density and temperature.
Water is most dense at 39 Fahrenheit (4 degrees Celsius), and as water warms or cools from that
mark it gets less dense. This has implications for a lake's structure because the denser water is
heavier and will be at the bottom of a lake while the less dense water is lighter and will generally
be at the top of the lake.
In the summer in Minnesota, the sun heats the top layer of a lake (called the epilimnion) which
causes it to become less dense. The bottom layer of the lake (called the hypolimnion) does not
receive sunlight and therefore remains cold. Since the top layer of the lake is less dense, it floats
on top of the bottom layer and the two do not mix. The metalimnion is the middle layer of water.
The metalimnion also encompasses the thermocline, the area of the most drastic change in water
In the fall in Minnesota, the sunlight is not as
strong and the nights become cooler. This
change in season allows the top layer of the
lake to cool off. As the water cools, the
density difference between the top layer of the
lake and bottom layer is not as great. Wind
can then mix the layers. Eventually the top
layer fades and mixes with the middle layer.
The thermocline sinks in the water column as
the heavier upper water layer forces it deeper.
Soon, though, the temperature in this mixed
upper layer equals that of the bottom layer;
wind easily mixes the entire water column because similar temperature and density exist
throughout. This mixing allows oxygen and nutrients to be distributed across the whole water
column again, and is called fall turnover.
The timing and duration of fall turnover depends on the size and depth of the lake. Sometimes it
can occur in a couple days and sometime it takes a week or more. The deeper the lake, the
longer the water column takes to become uniform in temperature since the bottom stays cooler.
Most lakes in Minnesota that are deeper than about 20 feet turnover in early to mid October.
You can track fall turnover in an individual lake a couple different ways. The easiest way is with
a Secchi disk and a water thermometer. A Secchi disk measures water clarity. During fall
turnover, the clarity of a lake usually decreases because mixing brings up nutrient rich water
from the bottom of the lake and causes the lake to look cloudy. Sometimes there is even a
distinct smell as decomposing plants, algae and other matter surfaces. Then, when turnover is
complete, the clarity increases dramatically. If you take Secchi disk readings and surface water
temperature readings every day or every other day in late September and early October, you can
track fall turnover. Once the surface is 39 degrees F and the water clarity is deeper than it's been
all summer, you will know that turnover is complete.
A more precise way to track fall turnover and the sinking of the thermocline is to take the
temperature at 2-foot intervals from the surface of the lake to the bottom. You can tie a rope to a
thermometer and mark 2-foot intervals on the rope. If you graph a line of temperature versus
depth in the lake, you can see how the lake cools off and becomes uniform in temperature after
Some people report that fishing is not as good during fall turnover. The main reason fishing is
harder is because the fish move and are more dispersed. In the summer, walleyes school in high
oxygenated holes and structures. When the lake mixes, the oxygen levels become uniform
throughout the lake so fish can roam anywhere. For information on how to fish during fall
turnover, visit:
Most lakes in northern Minnesota are considered dimictic, meaning they mix twice a year -
spring and fall. Shallow lakes, less than 15-20 feet, behave differently and can mix more often
throughout the summer.
Enjoy the lakes!


Grace Lake Association

2017 AIS Volunteer Ambassadors

 September, 2017 Schedule

Tue   5                         8-10 a.m.                     Bob Brouse                  333-0456

Wed  6                         8-10                             Ed Marthaler              949-929-5187

Thur  7                         8-10                             Dick Sampson              751-7220

Fri   8                           8-10                             Ron Milbrandt             766-5896

Mon  11                       8-10                             Jim Kramer                 760-3298

Tue  12                        8-10                             Jim Kramer

Wed  13                      

Thur  14                       8-10                             Dick Sampson

Fri  15                          5-7 p.m.                       Rick Black                    791-6298

Mon  18                      

Tue  19                        8-10                             Bob Brouse

Wed  20                       8-10                             Ed Marthaler

                                    5-7                               Doug Goodman           239-634-2262

Thur  21                       5-7                               Doug Goodman

Fri  22                          5-7                               Rick Black

Mon  25                       8-10                             Ron Millbrandt

Tue  26                        8-10                             Ron Millbrandt

Wed  27                       8-10                             Jon Blessing                 751-3784

Thur  28                       8-10                             Jon Blessing    

Fri  29                          8-10                             Jon Blessing

Grace Lake was well represented by members at the AIS Volunteer Training Session Friday August 25th 2017.  These members are now qualified to do volunteer inspecting at the Grace Lake Public Access.  

RMB LABS This is a great website whose service Grace Lake utilizes.  Please take some time and visit this site

Meeting Minutes are posted on MINUTES page.

CL-B to put $37.8 million referendum on November ballots

CASS LAKE -- About a week after they agreed to draft a stripped-down facilities plan, Cass Lake-Bena Schools leaders met again to put a different plan on ballots this November.

At  an Aug. 3 special meeting, the School Board agreed to ask voters to approve a $37.8 million bonding referendum this fall, pending state approval. If voters agree, the district would use that money to build a new school for grades 3-5 and renovate and expand some of the district’s existing buildings and classroom spaces.

To read the entire article click on the link below

Members of Grace Lake Watershed Assn. getting educated at the Starry Trek on the latest Aquatic Invasive Species STARRY STONEWORT.  The event was hosted by Bruce Anspach of the DNR.

Members of Grace Lake Watershed Assn. attended the Beltrami County Commissioners meeting last night at the Frohn Township Hall.

Please check out the newly added Sampson Presentation page LINK!!!


Rheta Mason is having her auction at her lake home on June 25th starting at 11 am.  Her address is 4803 E. Grace Lake Road SE.  Let's be there and create a buyer's frenzy!!

This is the Link for the video about Starry Stonewort we watched at the meeting.

Additional donations for Grace Lake can be made to the NW MN Foundation. Please specify Spendable Project Fund  or call 1-800-659-7859.

Northwest Minnesota Foundation

According to Bob Brouse life is "a bowl of cherries and maybe home made cookie when you live at Grace Lake"
I have to agree!!

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