The City of Prior Lake and Prior Lake-Spring Lake Watershed District (PLSLWD) staff continually monitor local conditions including winter snowpack, precipitation, and lake levels to assess flooding risk. Early spring is one time of year when flooding potential receives some extra attention. According to the National Weather Service office in Chanhassen, the weather outlook and the potential for snow or rain are the biggest wild card every year. At this point, additional rainfall would be the main spring flood driver.
Based on an analysis done by City staff, there isn’t a strong correlation between the lake level at ice-out and the eventual high-water elevation for Prior Lake in any given year. For example, in 2014 the early spring level for Prior Lake was very close to the long-term average of about 901.6 on April 20; the record flooding level of 906.17 recorded on June 30 was caused by above-average rainfall events over a period of a few weeks in May and June. Other years, such as 2001, start out with high lake levels (902.75 on 4/15/2001) but the lake’s high-water level for the year is recorded shortly thereafter (904.33 on 4/30/2001); in that case melting snow likely contributed to the high-water levels.
CURRENT CONDITIONS AS OF MAY 2, 2018: Ice-out occurred this week and there is no longer any snowpack in the watershed above Spring Lake and Prior Lake. Spring Lake levels have been declining for about a week, although it continues to discharge to Prior Lake. Prior Lake appears to have View Full Article →View Full Article