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Rules Around Lake Treatment


  • Department of Natural Resources (DNR) restricts weed treatment.
  • Treatment area cannot exceed 15% of a lake’s littoral area (15% Rule) unless a variance is allowed by DNR.
  • Lake Josephine is 116 acres, with 81 of those considered littoral, which gives us approximately 12 acres to work with.
  • Prior to 2013, our treatment plan has traditionally been:
    • 3.2 acres of shoreline spraying, individually contracted by homeowners
    • 7.9 acres of offshore spraying, contracted by the Association to benefit the entire lake
    • 1 acre must be held in reserve
  • If DNR deems that a lake has a significant weed infestation, it can allow it a variance to treat a larger area. This can be done through an independent variance process, which is done annually, or via a Lake Vegetation Management Plan (LVMP). The latter is a contract with DNR that allows for variances within its 5-year time horizon. The benefit to lakes is that they do not have to go through the lengthy and time-consuming variance permit process each year. In return, lake associations granted an LVMP must agree to lake monitoring to ensure that the treatment is effective and is not negatively impacting the lake and/or surrounding environment.
  • Coverage areas for variances differ, based on the type, nature and extent of the weed infestation and are determined by DNR based on lake mapping that is done in the spring.