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Erratic Lake Levels of Prior Lake

The lake level is measured in feet above sea level. The actual normal lake level is very difficult if not impossible to define but in the last decade 900.00 above sea level is to be considered somewhat average. Although the recent flood of 2014 and low lake levels of 2008 two 2009 are seen by most as extremes, history has seen far greater extremes.

the drought or dustbowl period during the 1930s caused prior Lake to separate into about six different in isolated small lakes and ponds varying from 11 feet in depth per body water Historic Lake Levels in Feet Above Sea Level

1930’s. 883.6 which is 19 feet below todays level of 902.5. Dust Bowl/Depression Years. Prior Lake was then divided into six small ponds. Shores were used to plant corn and potatoes

 

the 1950s relatively stable seen changes from a 94.0289 9.2 total deviation of 5.2 feet which by today’s standards are still quite erratic.

The 1960s were again erratic varying from 8952903.6 with a total deviation of 8.6 feet

1970s saw total deviation of only 4 feet.

The 1980s were the most erratic and catastrophic in order history with lake levels that would have risen to 918 if the outlet channel had not been built. This would have resulted in water overflowing highway 13.

The flood of 1983 was very similar to the flood of 2014 and that the lake Pete at roughly 904.7 on June 21. Subsequent heavy rains cause the lake to rise to 905.7,  three feet above the 2014 high of 902.17

the outlet channel running at full capacity will drain the lake at approximately 65 ft.³ per second resulting in a decrease in lake level of blank per day.

Relate this to a dry hot summer windy day evaporation can reduce lake levels by up to 3/8 inch per day

Prior Lake Outlet Structure:

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The outlet in normally set to start draining the lake when the water level reaches 902.5 but can but adjusted to lower the water level to 902.00 under certain circumstances.

 Pictures compliments of the Prior Lake Spring Lake Watershed District  For full description of the history and operation of the outlet structure:  http://www.arcgis.com/apps/MapJournal/index.html?appid=4f2b0e6974ea4a41a66e9138f1855c14

Pictures compliments of the Prior Lake Spring Lake Watershed District

For full description of the history and operation of the outlet structure: http://www.arcgis.com/apps/MapJournal/index.html?appid=4f2b0e6974ea4a41a66e9138f1855c14