Lake Report from the Department of Environmental Protection

Dennis, Mary

Gives Trophic state index (TSI) for 6 Mount Desert Island lakes for the summer of 1985. 'Overall, 1985 was a good year for Maine lakes. Many of the lakes had improved visibility compared to 1984. Out of a total of 133 lakes which we have a complete season of data for the last two years, a significant difference can be noted. Of these 133 lakes. 75 or 56% of them improved by at least .5 meters and only 13 lakes or 10% had a lower mean transparency of at least .5 m. We can most likely attribute this difference to the amount of precipitation and runoff for the last two years. 1985 was a relatively dry year with most months having below average rainfall. 1984 was a relatively wet year with May and June having much higher than normal rainfall. There is a dramatic difference between these years for many lakes. Differences in weather from year to year cause natural fluctuation in transparency. This is one reason it is necessary to have several years of data before an accurate assessment of water quality trends can be made.' /STUDY LOCATIONS:/ /MOUNT DESERT ISLAND/Bubble Pond/Eagle Lake/Echo Lake/Seal Cove Pond/Long Pond/Jordan Pond/