Lake History
Clear Lake Timeline Summary
(from Waseca County Historical Files)

1869 Waseca bans excavation of sand and gravel from the lake bottom for building materials.
1872 Millers attempt to drain lakes into Crane Creek to increase the flow of water past their mills on the Straight River.
1873 The State legislature prevents the draining of Clear Lake and other MN Lakes.
1885 The state of MN stocks carp in many lakes. Waseca sportsmen object.
1886 Maplewood Park established.
Early 1900's Clear Lake is popular for swimming and fishing, especially for large-mouth bass. Reports and boat liveries are located on its banks.
1926 DNR begins stocking game fish in Clear Lake.
1932 Fisheries supervisor Thaddeus Surber reports algae in Clear Lake.
1933 The State Department of Health investigates a fish kill in Clear Lake. Pollution sources noted include sanitary sewage entering storm sewers, and a ditch from the dump to Clear Lake, outlet known as "Andy's stink".
1938 First aerial photos show large slough between Loon and Clear Lakes is being filled in with trash and other fill.
1944 Regional Fisheries biologist James Groebner writes in 1963 that Clear Lake had good fishing and abundant submerged vegetation until 1940-44.
1951 Heavy rains raise the level of Clear Lake by 3 feet. Authors Jim Zimmerman and Tim Madigan (in the Streets are Wider Now) cite this as the beginning of Clear Lake's decline. Vegetation was submerged; carp and sheepshead multiplied.
1951 DNR Fish Survey.
1954 Copper sulfate is applied to the lake to kill algae.
1957 DNR Fish Survey.
1958 Copper sulfate is applied to the lake to kill algae.
1959 DNR Fish Survey.
1963 James F. Groebner, Regional Fisheries Biologist, writes the following about Clear Lake: "Carp and sheepshead have invaded the lake, most likely by means of Crane Creek. Carp are extremely abundant. Submerged vegetation is very sparse. Only a small area of bulrush is left. Algae are extremely dense. Bluegill and bass fishing are already greatly depreciated and pike and crappie fishing are going downhill."
1963 Waseca Sportsmen construct a rough fish barrier at the outlet of Clear Lake. DNR conducts a fish reclamation project in the fall of 1963. Toxaphene is applied to the lake to kill all fish prior to restocking with game fish. Overstocking of pan fish results in stunted fish.
1963 DNR constructs a northern pike spawning area on the east side of the lake after reclamation.
1964 Special investigation by DNR shows aquatic plants respond well and become more abundant after fish reclamation.
1974 National Biocentric Inc. reports on Clear Lake's nutrient budget. 70% of phosphorous and 80% of nitrogen are believed to be coming from urban runoff.
1975 US EPA awards city of Waseca a grant of $269,000 for the Clear Lake restoration Project.
1977-80 Sewer sampling and lake quality monitoring as part of the Clear Lake Restoration Project.
1978 DNR removes 30,500 lbs of fish, mostly small crappies, resulting in improved fishing.
1979 DNR Fish Survey.
1979 Two storm sewers are diverted into Gaiter Marsh for phosphorous removal before reaching Clear Lake.
1980 Storm water treatment marsh is constructed near the NW corner of Clear Lake.
1981 Storm water from the west side of Clear Lake, and the overflow from Loon Lake, are diverted into the treatment marsh prior to being discharged into Clear Lake.
1982 City limnologist John Barten reports that the treatment marsh removed 52% of total phosphorous in 1981 and 70% in 1982. Lack of detention time during rainfall is cited as a problem for the marsh. (Water should be held for 5-7 days.) A recently formed Clear Lake Restoration Advisory Committee is educating citizens on the proper use of lawn fertilizers, and attempting to reduce the garbage left on the lake during ice fishing.
1983 DNR Fish Survey.
1985 Dirk Peterson, Regional Fisheries Supervisor, reports on increased rough fish and reduced aquatic vegetation in Clear Lake.
1986 SW shoreline of Clear Lake is rep-rapped.
1987 DNR conducts second fish reclamation project using rotenone to kill all fish prior to restocking with game fish. Overstocking of pan fish results in stunted fish. 1992 DNR lake management plan says "Aquatic vegetation did increase for a short time after reclamation, but the City of Waseca constantly pumps water into the lake, maintaining artificially high (full) water levels which, in combination with the rip-rapped shorelines, do not allow the establishment of vegetation."
1988 DNR Fish Survey
1989 SE shoreline is rip-rapped.
1980's Rural homes without sewer service are surrounding the northern and eastern shores of Clear Lake. Annexation is discussed but not accomplished.
1980's-90's The City of Waseca upgrades sanitary sewers to prevent overflows of raw sewage into the lake and treatment marsh during heavy rains.
1988 The lake bottom is treated with alum to immobilize the phosphorous that is entering the water from the lake sediments. Alum treatments usually last about 10 years.
1988 Curly-leaf pondweed is first reported in the lake.
1989 County Water Plan is completed.
1990 The City of Waseca no longer employs a staff limnologist, having had one for approximately 10 years.
1991 Loon Lake alum treatment system is installed to remove phosphorus from storm water.
1992 DNR Lake Management Plan. Hugh Valiant, Regional Fisheries Supervisor. Discussion of habitat development and protection says, "A marsh enhancement project that has potential to improve the quality of water entering Clear Lake, as well as an increased area available for northern pike spawning, is in the early stages of coordination (with other agencies and the public) and proposal. We should work with the city of Waseca to design a water level regime that is favorable for aquatic vegetation.
1993 DNR Fish Survey.
1994 Clear Lake Aluminum Sulfate Treatment, Final Project report (draft), Jeff Lee. Phosphorous levels were reduced in the two years after the alum treatment.
1995 Water Management Plan prepared for the City of Waseca.
1996 City of Waseca lake committee no longer exists.
1996 Water quality monitoring of Clear Lake by the MPCA (with comparisons to Reeds, St Olaf). Clear Lake responded to intensive management in the 80's, but now phosphorous levels are very high and water quality is poor compared to Reeds and St Olaf lakes.
1997 County Water Plan update.
1998 Largemouth bass experimental regulation for Clear Lake.
1999 City of Waseca cuts funding for lifeguards at Clear Lake because use of the beach has declined.
2000 City sewer system is overwhelmed by heavy rains and overflows raw sewage into Clear Lake.
2001 City discontinues pumping water from treatment marsh into Clear Lake.
2001 2001 Waseca Lakes Association Founded. Started by President Duane Rathmann with help from the first lake board, Dale Schons, Barb Noble, Rick Roberts, Dave Baldini, Ron Purcell & Hank Olson
2001 to 2003 WLA samples all inlets and outlet to Clear and Loon Lake for phosphorus levels. A summary of the three year sampling can be found at the “water monitoring” tab on the WLA website.
2001 WLA begins monthly water clarity and water level recording in Clear Lake. Water clarity readings using a secchi disk and water levels can be found at the DNR lake finder website at:
2002 Clear Lake (DOW#81-0014) is listed on the 303(d) list of impaired waters due to excess nutrients.
2003 Extensive Loon Lake shoreline restoration project completed at Loon Lake Park by WLA with help from MN DNR and Waseca County Soil and Water.
2003 WLA commissioned Bolten and Menk for comprehensive study of Clear Lake completed with Blandin Foundation Grant.   Ditch 15-1 is implicated at the largest source of phosphorus to Clear Lake and recommended that the ditch should be abandoned and rerouted. A copy of the BMI report can be viewed at:
2004 WLA sponsors the first annual Lakefest Freedom run around Clear Lake on the fourth of July.
2004 First shoreline restoration plantings done at three locations around Clear Lake. More restoration projects on private properties done in successive years. Clear Lake park shoreline restoration done in 2012 as WLA partnered with Waseca County Soil and Water.
2004 AW Flyover of Clear and Loon Lakes completed to evaluate the effect of water pollutants related to land use and impacts within the near shore area. No major septic issues were detected in Clear and Loon lakes. Storm water point source influences of sediment from discharge area on NW side of Clear lake is detected with water penetrating photograph Pumping from filtration marsh into Clear Lake was diiscontinued in 2001. A copy of the fly over report and photos can be viewed at:
2005 Eurasian watermilfoil (EWM), first confirmed in Clear Lake by DNR. Clear Lake was put on the infested water list in 2006.
2007 Clear Lake Road and Trail project completed along with Maplewood boat landing and parking lot. Efforts made during construction include moving surface water away from Clear Lake or allowing for more filtering of surface water before entering the lake.
2008 Doggi bag dispensers purchased by WLA installed around Clear and Loon Lakes. Bags are filled by WLA volunteers and average annual usage is around 3000 bags.
2009 1st Waseca Triathlon held at Clear Lake Park sponsored by the WLA
2012 Loon Lake rotenone treatment to remove carp followed by 2013 installation of an aerator funded by WLA and operated by the city of Waseca. WLA held a fish fry at the American Legion to raise funds for the aerator.
2012 WLA makes first application of aquatic herbicide on 30 acres for control of invasive weed Curlyleaf pondweed (CLP) in Clear Lake. Cost of $7532 in covered by WLA funds and city, county as well as DNR grant. Applications are made each year following.
2013 MSU Water Resources Study of Waseca Lakes Completed. Total phosphorus (TP) load in Clear Lake is 78-91% higher than would be expected under relatively natural conditions. Proportionally, 53% of the TP entered the lake from the watershed and 47% was annually recycled from sediments and plants within the lake (internal loading). During the two year study, internal loading was the single most significant TP source. Gaiter Lake and the Maplewood subwatersheds were also significant contributors of externally loaded TP. A copy of the final report can be viewed at the “water monitoring” tab on the WLA website.
2016 Earliest ice out record on Clear Lake recorded on March 14, 2016. Ice out dates for Clear Lake going back to 1874 are posted on the WLA website at the “Water Monitoring” tab. In late May that year, a very heavy infestation of Curlyleaf pondweed (CLP) was noted in Clear Lake.
2016 13 inch rain hits Waseca over two days in August and causes extensive flooding of homes and businesses in Waseca. Clear Lake water level rises 14 inches.
2017 During ice out in late March 2017, over 34 bald eagles were seen at one time on March 19th sitting on the edge of a remaining ice sheet. Eagles often descend on Clear Lake near ice out to feast on fish.
2019 Eurasian watermilfoil (EWM) noticed expanding in small patches in Clear Lake.
2021 Increasing EWM combined with CLP severely hamper recreational boating and water clarity in Clear Lake. Waseca County commissioners agree to purchase a weed harvester from Lake Minnetonka for use in Waseca county lakes in 2022.