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Water Monitoring

WICOLA’s early efforts in water monitoring began in 1993 with the taking of Secchi Disc readings in our lakes. WICOLA started partnering with the Minnesota Pollution Control Agency (MPCA) in 2005 upon implementation of the Kawishiwi Watershed Monitoring Plan. The plan called for using the agency’s advanced Citizen Lake Monitoring Program (CLMP) protocols for volunteer monitoring.

Every summer, May through September, boats with 3 to 5 WICOLA volunteers, collect samples and take readings from specific, representative locations in our lakes. Currently, samples are collected from 5 lakes encompassing 10 locations: White Iron (1 location), Farm (3 locations), Garden Lake (1 Location), plus Birch (3 locations), and Fall (2 locations) Lakes.  All sites were identified and selected by the MPCA. WICOLA conducts the water sampling while the MPCA provides technical support.

The Process
Water monitoring is not difficult although certain procedures must be followed to ensure valid results. First, the location is verified with latitude/longitude coordinates as specified by the MPCA on a GPS unit in order to sample the same locations each time. At each location, volunteers take several readings and samples.

1. Water Sampling
Water samples are collected into bottles at a depth of 2 Meters for laboratory analysis. The collected samples are sent to RMB Labs where the actual tests are conducted with results sent to the MPCA. Test results include: Total Phosphorus, Total Kjeldahl Nitrogen, Sulfate, and Chlorophyll A.

2. Sonde Readings
A Sonde (or probe) is a specialized water quality monitoring instrument. Readings are conducted at the surface and then every meter throughout the water column down to the bottom and are recorded on a data sheet. Readings include:  Temperature, Dissolved Oxygen, Conductivity, and pH.

3. Secchi
Secchi Disc is a circular disk 30 cm / 12” in diameter used to measure water transparency. The disc is mounted on a line and lowered slowly down in the water. The depth at which the disk is no longer visible is recorded and taken as a measure of the transparency of the water.

4. Invasive Species
Invasive species tests are conducted at a depth of 15 to 20 feet. Water is collected in a specialized container with a magnifier and viewed on the surface to look for Spiny Water Fleas.

The Results

Collected water samples are submitted to RMB Labs (MPCA approved Lab) following MPCA protocols. RMB Labs sends the lab results to the MPCA which maintains the results in their database. The data is available for public access on the MPCA website (see link below). The results of these sampling and monitoring efforts are used to identify long-term trends in water quality and to identify “impaired” waters under the federal Clean Water Act. The MPCA requires 10 years of continuous data before they will consider identifying any potential trends. The federal Clean Water Act requires states to identify and list polluted or “impaired” waters. A lake or stream is impaired if it fails to meet one or more of Minnesota’s water quality standards. Standards exist for pollutants such as nutrients or sediment, which are directly related to water transparency. When nutrients or sediment are high, water transparency is low.

Water transparency data collected by WICOLA volunteers are used to determine the “aquatic recreation assessment,” which describes how well a lake can support uses such as swimming, wading, and overall aesthetics. Using the total phosphorus (a nutrient), chlorophyll-a (depicts the abundance of algae), and Secchi depth (water clarity), the “Trophic Status,” or level of biological productivity, of the lake can be determined.

The 10 year average of Total Phosphorus (TP), Chlorophyll-a, and Secchi transparency values are indicators of nutrient richness of a lake. Nutrient richness ranges from “oligotrophic” which are lakes low in nutrients to “hypereutrophic” which are very nutrient-rich. Oligotrophic lakes are unlikely to produce undesirable algal blooms while eutrophic lakes are very nutrient-rich and likely to produce unpleasant algal blooms.

The chart from MPCA (below) shows the results for White Iron Lake.

We are lucky that the White Iron Chain of Lakes exhibits very good water quality. As an example, here is MPCA’s description of White Iron Lake’s overall condition: “Suitable for swimming and wading, with good clarity and low algae levels throughout the open water season. Concentrations of mercury in fish tissue exceed the water quality standard; for specific fish consumption advice refer to the Minnesota Department of Health website at:

Results for all the sampling and monitoring are posted on the MPCA web page at where you can look up data on the White Iron Chain of Lakes as well as many other lakes in the state.