On Saturday morning October 10, 2015, the outlet control (weir) on the west side of Lake Independence was replaced under MN DNR permit #2014-0199. The project was completed entirely with local talent and volunteers saving the community several thousands of dollars. The cost of the project will be shared by the cities of Independence and Medina, Three Rivers Park District, and the Pioneer-Sarah Creek Watershed Management Commission.
The weir, located under the bridge on Independence Road, is a wooden dam structure previously installed in 1977, which was worn and damaged. It was scheduled to be repaired following the recent outlet channel restoration that was completed in 2014.
The top boards of the weir were replaced with two 25' long 3" thick white oak planks (each weighing about 150 #) custom cut by Timm's Lumber & Sawing (County Rd 6) and covered by a custom made 3/16" plate steel cover formed by Schoening (County Road 90). All components were welded and prepared by Larry Ende, City of Independence Public Works Director.
The new weir was installed by Larry Ende (Director - Independence Public Works), Joe Baker (Pioneer-Sarah Creek Watershed Commissioner), Derek Spencer (Delano Troop 273 Eagle Scout), Mike Peterson, and Brad Spencer (Independence City Councilmember). with Project Engineering services by Craig Jochum (Hakanson Anderson Associates, Inc.)
Photos by Brad Spencer - free to distribute.
New oak planks and steel plate await installation. A broken section of the old top plank lies between the 2 new boards.
Weir installed - steel plate cap barely visible at water's surface. Left to right: Derek Spencer, Joe Baker, Mike Peterson
Close up setting runout. Left to right Derek Spencer, Joe Baker, Mike Peterson, Larry Ende
Thank you to everyone who helped bring this project together!
Water Quality – Lake Independence
Lake Independence is an 851-acre lake located within the municipal boundaries of Independence and Medina. Over the past several decades, the lake has experienced increasingly impaired water quality that has reduced the lake’s recreational and aesthetic value. In 2003, the lake was designated as an impaired water body by the Minnesota Pollution Control Agency (MPCA) based on its recent water quality history (MPCA 2002 303(d) list).
To better understand the factors that have been affecting the water quality of Lake Independence, Three Rivers Park District initiated a comprehensive monitoring plan. Inflow monitoring results and computer modeling identified major sources of pollutants within the Lake Independence watershed and allowed for the characterization of flow volumes, pollutant concentrations, and overall loadings for each inflow site. The primary goal of the study was to develop a list of potential management actions and estimate their associated costs, effectiveness, expected longevity, and technical feasibility based upon the observed field data, computer model predictions, and characteristics of each potential source.
The Lake Independence Diagnostic Feasibility Report identified potential nutrient sources that have contributed to poor in-lake water quality. It was determined that there has been a considerable amount of nutrient loading from the watershed as well as an in-lake internal loading component. The study identified several best management practices (BMPs) that could be implemented to improve the lake’s water quality.
In 2004, Three Rivers Park District and the Commission met with the Minnesota Pollution Control Agency (MPCA) to begin the TMDL process. A TMDL is the sum of the allowable loads of a single pollutant from all contributing point and nonpoint sources that a waterbody can receive and still meet water quality standards. The Feasibility Report formed the basis of the TMDL project. A final report was sent to MPCA when the project was completed. The final report includes an assessment of the lake, a description of project activities and results, a plan for the allocation of pollutant loads, a public outreach plan, and an implementation plan to achieve and maintain water quality standards.
A Stakeholders Committee comprised of representatives from the Lake Independence Citizens Association, the Cities of Independence and Medina, the Independence Horse Owners Association, Medina Horse Association, the Pioneer-Sarah Creek Watershed Management Commission, Three Rivers Park District, Hennepin County Environmental Services, agricultural producers in the watershed, and at-large citizens met to develop the work plan and determine water quality goals for the lake.
The Committee agreed that reductions from six phosphorus sources were needed to achieve the water quality goal of 36 ppb (parts per billion), a reduction of 23% in the current nutrient loading to the lake. Those sources were identified as agricultural cropland, animal waste, urban development, failing individual sewage treatment systems, the Loretto Sewage Treatment Facility, and geese.
Following a public meeting in September 2005, the Cities of Independence and Medina, the Stakeholder Committee, Three Rivers Park District, MPCA, and the Commission met to discuss the waste load reduction allocations, determine what BMPs are financially and socially acceptable, develop a time line for implementation, and discuss potential funding sources and the consequences of non-compliance.
The final Lake Independence TMDL work plan was submitted to MPCA and the Board of Water and Soil Resources on February 26, 2007. The TMDL is published in two formats – the version approved by the Environmental Protection Agency dated January 2007 and the March 12, 2007 version that includes the expanded Implementation Plan.