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Historical chlorophyll data suggest the take's algal blooms are somewhat greater than would be expected for the lake's phosphorus concentration. The long term growing season chlorophyll a concentration from the lake's epilimnion (11.5 mg/m') is approximately half of the most recent summer average (19.6 mg/m3 in 1991). The data indicate the lake is responding to its nutrient load by experiencing more algal blooms than expected. As shown in Figure 4-13, growing season mean chlorophyll concentrations were generally within the mesotrophic category during the period of record (1971-1991). Exceptions occurred during 1984, 1987, and 1991 when the mean was within the eutrophic category. This simply means that the average level of algal blooms noted in the lake have generally been moderate, but have been at an undesirable level in recent years. However, algicide treatment in 1990 reduced the algal blooms to a moderate level. Even though the historical data suggest the lake's water transparency has been good, the lake experiences water quality problems during the late summer period, as noted earlier. During the period 1971 through 1992, the average growing season water transparency remained within the mesotrophic category. These data suggest the lake had relatively good water transparency throughout the period of record. However, the average fails to depict the annual decline in water transparency, which results in a public perception of undesirable water transparency by late summer. As mentioned previously, treatment by an algicide during 1989 and 1990 may have improved the late summer water clarity somewhat. Problems with aquatic vegetation in recent years necessitated chemical treatment in private beach areas around the lake. The lake was chemically treated to control weeds during 1989 through 1993. Specifically, an area that included 2,985 feet of shore and extending approximately 150 feet from shore was chemically treated. This is 10% of the littoral area, which is the maximum allowed by the DNR. Treatment was completed by a professional, and coordinated by the Lake Jane Association. 4.2.9.5 Public Use and Related Water Quality Concerns Lake Jane is very heavily used for a wide variety of recreational uses. Uses during the ice -free period include swimming, fishing, boating (speedboats, canoes, pontoons, and fishing boats), waterskiing, and passive uses by.lake residents. During the winter months the lake is used for ice fishing, ice skating, and snowmobiling. A public boat access wasconstructedalong the south shore of Lake Jane in the fall of 1980. The number of individuals accessing the lake is limited, however, by the 10 parking spaces in the public access. A DNR recreational survey completed in 1980 indicated fishing pressure in the lake was 38.71 angler -hours per acre, which is near the Metro Region median. Boat anglers comprised approximately two-thirds of all anglers. It is likely that the recreational survey was completed prior to the completion of the boat access. The Tri-Lakes Association is a local organization which is interested in preserving and improving water quality. It consists of residents .of Lake Jane, Lake Olson, and Lake DeMontreville. Although Lake Jane does not have a public swimming beach, the lake is heavily used for swimming. Residents have private swimming beaches, which receive heavy usage during the summer months. Swimming lessons are offered at the lake each summer, and from 30 to 60 individuals generally participate. A large amount of open space is located along the shoreline, and is expected to remain undeveloped because of wetlands, etc. A large number of wildlife and waterfowl have made 23\82\045\SEC4.RPT\KMH 33 DRAFT: June 23, 1994