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• Phosphorus is a nutrient. Too high of levels of phosphorus are not desirable because it stimulates algae bloom or"dog days" in July and August. Phosphorus levels in the lake can be reduced by limiting the man-made sources. It is especially important to work watershed wide on this issue because of the extremely large watershed to lake ratio previously discussed. If all of the man-made sources of phosphorus entering the lake and watershed were eliminated the lake will still experience algae bloom and dog days. However, the intensity and duration of the algae blooms can be reduced. The lake improvement project proposed will not significantly reduce the level of phosphorus in Lake Orono. The task force will be addressing this issue by other means. For details on phosphorus see page#13 of the study. Fecal coliform - Fecal coliforms are bacteria associated with waste matter and are of concern regarding diseases transmission. The city's waste water treatment plant has the ability to test for fecal coliforms and aided in the sampling of Lake Orono. In the summer of 1997, the city began routine monitoring for fecal coliforms at Orono Beach and found significantly high levels. The city undertook efforts to track the source of this contamination. Water born fecal coliform is relatively short lived ( 1 to 2 days) so the search for possible sources did not have to be conducted very far upstream. Because most of the area • in the immediate vicinity of Orono Beach is served by city sewer, city staff became suspicious of the findings. It is theorized and it stands to reason that fecal coliforms of animal origin are not as great of a health threat to humane as fecal coliforms of humane origin. Staff did fecal streptococci analysis and fecal coliform analysis simultaneously and compared their ratio. It was determined that the high fecal coliforms were of animal origin. It is theorized that geese are the likely source. The city will conduct weekly monitoring of fecal coliform levels at Orono Beach during the swimming season. Page #15 of the attached study contains the fecal coliform test results. Sedimentation Suspended sediment - Inlet and outlet monitoring revealed that more suspended sediment is leaving the lake than is entering it. This is not surprise considering the granular nature of the materials upstream of the lake. This finding did not consider inlake generated suspended sediment formed from decaying organic matter agitated into suspension by boat traffic, but none the less, suspended sediment is not a major issue. For additional details on suspended sediment see page#10 of the study.