Ordinary High Water Level (OHWL)

The OHWL is an elevation delineating the HIGHEST water level that has been
maintained for a sufficient period of time to leave evidence upon the landscape, commonly the point where the natural vegetation changes from predominantly aquatic to predominantly terrestrial. 
Clearwater Lakes OHWL is 1251.1 feet above sea level.  .1" is a little more than a 1/16 of an inch.   If you are reading the gauge on the side of the dam - OHWL is 4.73.  The DNR expects the water level to fluctuate 6 to 12" above or below this level.

Why does our water get high?

Picture
Where does our water come from?
Clearwater lake is an underground spring fed lake.   That means we have no direct river or stream that fills our lake.   Our water level is a direct result of rain run off and raising water tables that feed the underground springs.  That also means that our lake level is not controlled by the outflow from another lake. 

Where does our water come go?
Clearwater Lake is the headwaters of the Nokasippi watershed. That means that water leaves our lake through the Nokasippi river, flows through Eagle lake onto Nokay lake and eventually reaches the Mississippi River. 

Why is the water so high?
When more water flows into the lake then flows out water levels rise. After a big rain, it is a natural for the water to rise until the excess flows out through the Nokasippi watershed. When things interfere with the "natural" flow our water levels stay high.
So what could interfere with the lake returning to it's normal level? And what can we do?
There can be both natural and man-made bottle necks in the Nakasippi.  The board and many member volunteers have been very active on trying to bring our water level back to normal levels.  As with most issues, there is not a simple answer but a combination of issues.
Road Culverts
There are multiple culverts between Clearwater Lake and Nokay lake where the water flows under a road.   Some are under private roads.  The first culvert in flowing out of Clearwater Lake is under CR 8.
Culverts can become a problem in 2 ways. 
  • The culvert is only so big, so it can reach a maximum throughput.
  • The culverts can become blocked with debris.  This prevents water draining away.  It is dangerous to unblock the culverts.  Do not attempt to do this yourself. 
The Clearwater Lake Conservancy board keeps an eye on the Culvert on CR 8.   However, the county is responsible for clearing the culverts and has expressly told the Clearwater Lake Conservancy representative that we cannot clear the culvert ourselves.
Picture

Natural Vegetation
Natural vegetation slows and filter the water.    Under normal water levels this is good.   It prevents flooding and the filter process cleans the water.  It also provides habitat for a variety of wildlife.
Man-made Dams
There are 2 man-made dams in the Nokasippi watershed.  You can see one of the dams at the Clearwater lake boat launch.
Dams of this kind are under management by the DNR and the board has worked with them to keep our lake levels normalized. 
Picture
Beaver-made Dams
The board monitors for beaver dam activity every year.    Beaver dams will stall the natural flow of Clearwater Lake down through to Nokay Lake.    There have been times when Clearwater Conservancy has been contacted by residents on Nokay Lake concerned over their low water, while on Clearwater we have been concerned about high water.    When this happens we start looking for beaver dams.

The area between Clearwater lake and Nokey Lake is a perfect habitat for beaver and if a colony of beaver is removed there is no territorial competition and sooner or later a new colony will move in.  So this will always be on on-going concern.   A stable balance between beaver, high-water and low-water is our goal.
Floating Bogs
The waterway from the boat landing to the lake is lined with bogs.   Parts of these bogs can break off in storms or through damage.   The bog location and the current downstream draws these floaters right into the dam at the boat landing.   This causes a natural dam that interferes with the water flow.

Bogs are difficult to deal with because the can be very heavy.   The DNR does not allow us to remove them from the lake if there is any vegetation growing on them.

Snowmobiling over the bogs can cause damage that results in them breaking free in the spring.    The bogs are also a protected wetland area and you are not allowed to snowmobile through them.

The Clearwater Lake Conservancy Board obtains permits each year to remove these obstructions.  There is no charge for the permits.