Water Level Reporting

 Instructions for reporting the water level of Dead Lake to the Minnesota DNR

DNR West Dam

DNR East Dam

  1. At the East Dam, read the number from the left gauge of the dam.  Call the Fergus Falls DNR at 218-739-7576, ext 227 leave a message or e-mail Carla.koski@state.MN.us
  2. State that “you’re from the Dead Lake Association and you’re reporting the water level of Dead Lake on (date) from the East Dam.  The reading is (example: 2.75 Feet) and was taken from the LEFT gauge on the dam.”

Dead Lake Water Outlet Locations:

There are two water outlets for Dead Lake.  The East Dam (weir) is located in Indian Bay.  The West Dam is located in the south central part of Dead Lake.  The Minnesota DNR refers to these water control structures as the East Weir and the West Weir because a dam’s general purpose is to retain water versus a weir thatcauses water to pool behind the structure (not unlike a dam) but allows water to flow over the top.

 

Dead Lake’s Ordinary High Water Level (OHWL) as defined by the Minnesota DNR, is 1,327.8 feet above sea level, however, the East Dam level is set lower than this elevation.  Ordinary High Water Level 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.”

 

The East Dam:

For convenience, the East Dam has two vertically-mounted water level gauges with a gauge mounted on each of the weir’s opposing concrete abutments. The vertical gauge extends down into the water and “zero” on the gauge on the right abutment as you face downstream is 1,324.85 ft. above sea level (Datum adjusted 1912).   The zero of the gauge on the left abutment as you face downstream is 1,324.88 ft. (1912 datum) as of a survey in March 2003.  Therefore, if the lake’s surface water level is measured on the left abutment gauge at 2.75 ft, then the lake’s surface level is 1,324.88 + 2.75 = 1,327.63 feet above sea level.  Historically, Dead Lake water level has continued to rise from April thru May, June or July depending on precipitation, then decreases by Fall.  The range over the year has been about one foot.  Facing the weir from the Dead Lake side of the weir and looking down stream to the south, the water level gauge that’s mounted on the weir’s left abutment is the preferred gauge to be used by our volunteers to measure the water level because two gauge plates are mounted on top of each other with the top of the gauge reading 6.74 feet. The two gauge plates on the right concrete abutment are off set with the top of the higher section reading 5.34 feet.  Although it appears that the measurements on both of the weir’s gauges are set at nearly the same elevations, gauge reading must be associated with the location of the gauge and its correct gauge “zero”.

There is also a long-established DNR Permanent Gauge on the right upstream abutment of the west (natural outlet) weir or dam.  The gauge zero of this gauge is 1325.07 (1912 datum).  [Condition of this gauge is fair].

 

Gauge Reading Volunteer Opportunity

Any Dead Lake volunteer can submit a gauge reading by phone, e-mail or preaddressed postcards to the Minnesota DNR office in Fergus Falls, MN.  Because the two gauges have similar ranges of numbers, the DNR will need to know clearly each time which gauge (as one looks downstream) is being read.  The Dead Lake Association has permission to access the gauge by land from the property owner, Laurie Austrum.  The volunteer can also view the gauge with binoculars from a boat at a safe distance.  Once the raw measurement, such as 2.75 ft. from the East weir gage, has been taken, the volunteer should communicate the results to Carla Koski, carla.koski@state.mn.us, 1509 1st Ave N, Fergus Falls, 218-739-7576, ext 227. 

 

History of the Dead Lake Dams:

The project of building two dams on Dead Lake began in 1937 and was completed in 1938.   During the early 1930s, Minnesota and much of the nation were suffering with high unemployment due to the economic depression as well as severe depletion of water resources caused by a prolonged drought. To address these problems, various federal work relief agencies were established, primarily the Civilian Conservation Corps (CCC) and the Works Progress Administration (WPA). The stated purpose of the programs was to provide work for the unemployed and to benefit Minnesota’s water conservation program. As a result, approximately 350 lake level control dams were built throughout the state between 1935 and 1941, under the sponsorship of the Minnesota Department of Conservation. DNR Waters owns 302 of these dams and is responsible for their ongoing inspection, maintenance and repair.

 

CCC/WPA dams typically feature a reinforced concrete overflow structure with adjacent earthen dikes. After approximately 10 years of stop log manipulation, each dam was set at a permanent stop log level with no further manipulation intended or desired.  The Minnesota DNR conducts periodic inspections of these dams to ensure that each is at its authorized stop log setting and is functioning properly. Often, a dam may require some type of maintenance or repair, such as: • replacing missing or leaking stop logs, (sometimes with steel channels to reduce the frequency and cost of ongoing maintenance), refurbishing earthen dikes that deteriorate over time due to wave action, erosion, or foot traffic. grouting or patching a spillway where removable stop logs have been replaced with concrete, removing floating bogs, beaver clippings and other debris that may restrict flow and cause lake levels to rise, cutting down and removing trees growing near concrete structures to prevent roots from displacing or breaking abutment walls, cleaning, repairing or replacing metal gage plates that are attached to wing walls to measure lake level fluctuations.

 

Recent Maintenance on the Dead Lake Dams:

The East Weir that’s located in Dead Lake’s Indian Bay is a permanent, non-adjustable concrete structure with an “angle iron” style steel cap.  This structure replaced the adjustable “stop logs” that were used in the original design of the dam in the 1930s.  In 2007, the elevation of this steel run was set at 1,326.94 ft. above sea level.  This is slightly higher than the “authorized” 1,326.7 ft. elevation because the repair of the weir was designed to mimic a 2” board and channel iron that was in place on top of the weir prior to the 2007 repair work.

The mid-section of the West Weir was removed by the Minnesota DNR and no longer controls the water level.  The only remnants of this weir are the left and right concrete wing walls or abutments with a gauge on the right wing wall and a wooden foot bridge attaching the two wing walls.     

 

East Dam built in 1937 - 1938:

West Dam 1937 – 1938;

1941- 1994

 

Doug Martin

June 1, 2012