08/27/2008 Env Bd Packet - Laserfiche WebLink

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ENVIRONMENTAL BOARD MEETING JULY 31, 2008 Mr. Asleson presented his staff report to the Environmental Board members. Mr. Matt Kocian from Rice Creek Watershed District (RCWD) presented a PowerPoint presentation to the Environmental Board members on Reshanau Lake Water Quality, Curlyleaf Pondweed and Future Lake Goals. Reshanau Lake is considered impaired by the Minnesota Pollution Control Agency (MPCA). An impaired waterbody does not meet basic water quality standards set by the Environmental Protection Agency (EPA). Reshanau Lake is not alone, there are 1,475 listed impaired waters in Minnesota. Within RCWD and Lino Lakes there are many water quality impairments. There are different types of impaired lakes. The primary nutrient that causes impairment is phosphorus. Phosphorus fuels algae growth, causing lakes to turn green. According to Mr. Kocian the phosphorus in our lakes exceeds standards by the MPCA. There are many sources of phosphorus both external and internal. The main Curlyleaf Pondweed non - native submerged aquatic plant is a product of excessive phosphorous loading. Curlyleaf Pondweed's life cycle starts with sprouts in late October. The sprouts survive under the ice during the winter months. The sprouts rapidly grow soon after ice -out with dense growth by late spring and death/decomposition by mid- summer. Decomposing plant matter releases phosphorus. Control Options for Curlyleaf Pondweed include mechanical (cutting) which is very expensive and does not remove all of the plant and herbicidal treatments that have been done the past three years. This year will be the fourth year. Ms. Hartley questioned if the entire lake was treated. Mr. Kocian stated the entire off shore portion of the lake was treated. In 2005 RCDW treated 50.5 acres and the following years they treated 282 acres. The Curlyleaf Pondweed seedbank are turions and remain in the sediment and continues to grow in spite of treatment. It will take more than five years for herbicide treatment of this lake to rid it of Curlyleaf Pondweed. The cost of treatment is roughly $35,814. The herbicide is dripped, not sprayed out into the air. Herbicide treatment has been very effective. There has been no Curleyleaf Pondweed growth at Site 1, Site 2 and Site 3 after treatment. Goals for Reshanau Lake Management: 2 DRAFT MINUTES