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GLWMO MINUTES JANUARY 24, 2008 PAGE 6 These are preliminary results. He referred to the maps that showed the locations where runoff was monitored, where water quality was monitored, and where sediment core samples were taken. The southern location monitored for water quality is approximately 20 feet deep; the northern location is much deeper. The southern location showed higher levels of concentration of phosphorous than the northern site. The northern site meets GLWMO and MPCA goals for water quality; the southern site does not meet those standards. One of the reasons for the high level of phosphorous at the southern site is the presence of significantly more curly leaf pondweed. After mid-June, the sample showed an increase in phosphorous at the time when pond leaf decays and releases phosphorous. In the past year the northern part of the lake has experienced a significant drop in phosphorous concentration because the summer was very dry and very little runoff was let into the lake. Although the Lake Association has treated the lake for milfoil, it has not targeted curly leaf pondweed. Stark stated that the Board should meet with the Lake Association and come to an agreement about treatment. The levels of chlorophyll meet goals set by GLWMO, but the level at the northern site does not meet MPCA standards for deep lake water quality. A trend analysis using water quality data over the last 10 years shows that through the 1980s and 1990s, phosphorous levels exceeded MPCA criteria. Levels of chlorophyll follow the same trend. Maloney stated that the perception of water quality depends on where residents live because of the differences between sampling sites. He asked if it is typical to see this wide a range of data between sites. Mr. Sobiech answered that it is typical. Mogg asked the number of sites data is collected by Ramsey County and if there has been a downward trend from 2005 to 2007. Sobiech answered that Ramsey County collects data from one site. There has been a downward trend in phosphorous, an equitable trend in chlorophyll and a flat trend in water transparency. Aichinger noted that the MPCA uses samples over a period of 10 years to set impure water standards. The last 10 years of samples from Lake Owasso show levels below MPCA requirements. The algae concentration makes it difficult to determine turn-around trends. Water transparency depth averages 1.6 meters, which is below several standards. That was the reason for this study. Mogg stated that the Board needs to state why the study is being done based on the data presented and with the way the study plan was written and authorized. It is good that the numbers are going down. He would like this study to reference the earlier diagnostic feasibility report that was done in 1991 and tie the two reports together.