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GLWMO MINUTES JANUARY 24, 2008 PAGE 9 but major changes are not expected. Climatic changes--a wet day compared to an average day.. The impact from the road work done in 2007. There also needs to be a BMP analysis--management of curly leaf pondweed, internal loading sediment, a shoreline restoration analysis to see if anything has been done to improve water quality of the lake. Also, data was submitted to consultant D. Shapiro to look at any relationship between the size of the lake and the number of zooplankton and water quality. Preliminary findings show a lot of small zooplankton in the lake. A closer look is needed because fish are not eating them. And analyze transparency by depth. Mogg stated that the phosphorous models for this study and the one in 1991 are quite different. This model shows a total of 626 pounds. The previous study showed 2,415 pounds. Sobiech stated that one main difference is the amount of precipitation. Another difference is that in the old study the calibrations are not as detailed as the present models. When looking at the long-term record between 1994 and 2007, more unit runoff per acre is measured per year of an area, which is compared to literature published data. These models measure 6.5, which is right in the range where they are expected to be for this type of watershed. When water volumes are backed out of the previous study, the measurement is in the 10 to 12 range which could easily be accounted for in precipitation. Stark stated that his concern is that 2007 was an abnormal year and, therefore, questions the information. He asked if another year of samples should be taken. Sobiech stated that it is important to monitor the southern site where only one storm event occurred and at the Central Park east site. It would not be necessary to take samples again from the north site. It is important to continue to monitor the west side of the lake where there is a large drainage area. Other things that would be helpful would be to do periodic checks on larger wetlands like Lake Judy, Lake Emily and Lake Bennett. How much water is really infiltrating and discharging? More water is needed coming off the watershed than rainfall which is impossible or need to have extreme groundwater rate into the lake which doesn't seem possible. Eckman noted a variable of tree maturity in phosphorous levels. Aichinger stated that there are some variables in that lake monitoring data was not collected during leaf fall. It was done in September. The trend will be seen in the spring. Sobiech stated that spring concentration appears to be steady--20 to 30 micrograms per liter. If the plan is to collect more data, he would hold off on further analysis. Otherwise, there maybe extensive recalibrations. This is a good time to decide whether to hold off until more data is collected or proceed with the data obtained and make those recommendations. Aichinger stated that the concern is would recommendations from the current data incorrectly assume internal loading be less of a factor. In a normal precipitation year, that might not be seen and the BMPs would be totally different.