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4 Carman Bay was one of three Lake Minnetonka bays involved in the Lake Minnetonka Milfoll Project in 2006. This project assessed various technologies and approaches for conducting large-scale herbicide treatments to control EWM, and was the impetus for the formation of the bays' Lake Vegetation Management Plan, 5 Aquatic invasive plant management in Lake Minnetonka is focused on the lake's numerous bays, because the bays contain most of the lake's littoral zone and therefore the majority of aquatic plant growth. 6 The bay is In an urban/suburban landscape dominated by development. 7 The lake is considered an impaired water for mercury, and the Minnesota Pollution Control Agency (MPCA) has issued a consumption advisory for fish caught in the lake. 8 Lake Minnetonka is classified as a General Development (GD) lake. GD lakes have structure setbacks of 50 feet above the Ordinary High Water Level (OWHL) for sewered structures and 75 feet for unsewered structures. 9 Public access to the bay is available at several points. The City of Orono owns three parcels on the lake, and the lake can also be accessed via city rights of way on four streets. One of these, Lydiard Avenue, has a beach swimming area. The DNR does not operate any boat landings or water access points on the bay, but it is easily accessible via main Upper Lake Minnetonka. 10 Secchi depth readings have a 5 -year (2006-2010) summertime average of about 8.5 feet. The lake's trophic status is mesotrophic, and it fully supports surface recreational use. Water quality is monitored by the Lake Minnetonka Association or its agent3. 11 The proposed method of the Lake Improvement District formation is by citizen petition. issue Analysis Aquatic Invasive Species Manaeement EWM was discovered in Lake Minnetonka in 1987, and is currently the most problematic plant in Carman Bay. It is the second most abundant plant in the bay, after the native Ceratophyllum dermersum (coontail). EWM grows in dense mats on the water surface, interfering with surface recreational use, and can grow over and choke out native plants. The LMCD and the LMA have adopted the goal of reducing EWM coverage to a maximum of 20% in Carman Bay to reduce interference with surface recreational use, maintain or increase frequency and richness of native aquatic plants, and maintain or increase water quality. Current treatment and monitoring regimens are described in a DNR -approved Lake Vegetation Management Plan (LVMP), with the Lake Minnetonka Association serving as project manager. The current LVMP addresses AIS management in several Lake Minnetonka bays (Grays, Phelps, and North Arm, in addition to Carman), and includes a variance approval to treat more than the standard 15% littoral area with herbicides. Although frequency of CLP has been drastically reduced, EWM remains at nuisance levels and supports the granting of the variance. Section 7: Conditions of APM Permits and Variance, restricts herbicide treatment to a maximum of 96 acres and prohibits treatment within 75 feet of areas with bulrush or water lilies. Table 3 of the LVMP lists several aquatic plant management monitoring requirements. If approved, the DNR expects the LID to continue AIS management work under the guidelines and requirements of the LVMP, and to take over the responsibilities in Table 3 unless otherwise carried out by the LMA or the LMCD. The herbicide treatments regulated under the LVMP are only one component of a comprehensive EWM and CLP Management Plan, developed and overseen by the LMCD, for all of Lake Minnetonka. This comprehensive plan includes not only systemic herbicide treatment, but also spot herbicide treatment 3 Lake Mlnnetonka; Phelps, Carmans, Grays and North Arm Lake Vegetation Management plan, May 30, 2014