Lake Water Quality Management Areas
In order to more efficiently and completely address the different specific problems facing different lakes, the District has identified eight Lake Water Quality Management Areas.
Basis for defining LWQMA’s
While all boundaries are based upon subwatershed (drainage) areas, subwatersheds were included in a particular case based upon several criteria which received different weights for different LWQMA’s. The general rule was that areas should either have some functional connections, or should be relatively homogeneous in terms of lake characteristics. The following specific criteria were given consideration: Physical attributes, Water Quality attributes or problems, Subwatersheds contributing to nutrient loads, Development characteristics, Contiguity.
Lake Water Quality Management Areas
Lake Management Project
In its 2005 revised management plan, the District declared its intention to prepare vegetation management plans for several lakes. This was the result of growing problems associated with the treatment of flowering rush, both in terms of treatment measures and administrative mechanisms. After the Plan was adopted, flowering rush problems worsened, and problems with other aquatic invasive species emerged.
In 2008, the Managers started the process of preparing a plan for seven lakes which by then had been infested with flowering rush and other invasive species. As the process proceeded, it became clear that some aspects of the management of invasive species transcended the seven lakes, potentially extending to all lakes in the District.
Soon after the completion of that Plan, the District was petitioned by the City of Detroit Lakes for a District-wide project to address Aquatic Invasive Species. The proposed project known as the “Pelican River Watershed District Aquatic Invasive Species (AIS) Control Project, Project LMP-1”
Click here to read more about the District Invasive Species control efforts and projects.
Project Plan/Engineer's Report LMP-01
Aquatic Plant Management Plan
Aquatic Plant (Weed) Harvesting Projects
A Brief History
Aquatic plant harvesting has been a very important activity for the District and has consumed a significant amount of time and resources throughout its history. Within a few months of the inception of the District, a petition from Melissa-Sallie residents called for establishment of a project to remove lake weeds. It was conventional wisdom among limnologists of the time that the most practical way of reducing nutrient levels in lakes was to remove plant material (which contains large quantities of nutrients). Indeed, the 1967 Overall Plan prominently featured mechanical removal of excess aquatic plants as a means to address lake "eutrophication". In 1968 the District established the first of three projects (Watershed District Project 1) aimed at removing aquatic plant material from Sallie and Melissa. Originally funded in large part by grant money and donations from teh City, County and lake associations, Project 1 operated off and on until 1978. It was succeeded by Project 1a in 1978, and 1b in 1985; successor projects relied heavily upon donations from the District general fund, as well as direct assessment to affected lakeshore property owners.
After several years of systematic evaluation which received national attention from limnologists, research by Dr. Joe Neel (UND) concluded that significant nutrient reduction could not be brought about by harvesting. In the early 1970's the District shifted its harvesting emphasis towards reducing aquatic plants in order to enhance boating and swimming. A Detroit harvesting project 1C was established in 1990, with the added control of the exotic plant, Flowering Rush, to its project purpose. Beginning in 2003, the District began experimenting with herbicides to control Flowering Rush under the auspices of the Harvesting Projects. Currently, Flowering Rush is managed chemically. Click here to read more about the District's Flowering Rush management.
The project continued to harvest Curly-leaf Pondweed through 2014. In 2015, the District began to chemically treat Curlyleafed pondweed on Lakes Detroit, Curfman, Sallie and Melissa. With the success of these treatment, the District felt confident in selling the last mechanical harvester.