Water Quality Monitoring

Protect our Water Quality with “Shoreland Best Management Practices”

If you live at the lake, you can make a significant impact — pro or con — on Lake Vermilion’s water quality. How we each manage the shoreland on our property affects the lake we share. Check out these Shoreland Best Management Practices Fact Sheets assembled by University of Minnesota Extension. They cover a wide range of topics, including landscaping, erosion, septic systems, water wells, construction, lawn & gardens, woodlots, and wetlands.

Advanced Water Quality Monitoring in 2008 by Mel Hintz

Edited from an article in the November 2007 issue of The Vermilion Sportsman

clmpFor over 30 years, the Vermilion Lake Association has been actively involved in monitoring the water quality of Lake Vermilion. Recently, this activity has largely involved the collection of secchi disk readings and water surface temperatures as part of the statewide Citizen Lake Monitoring Program (CLMP) administered by the Minnesota Pollution Control Agency (MPCA). The Secchi disk readings measure water transparency, which is strongly correlated to water quality. These readings are reported to the MPCA at the end of each monitoring season and are published in a state-wide annual report on their website.

Editor’s note: The MPCA has compiled historical Secchi data specific to Lake Vermilion.

The MPCA also administers a more advanced program called CLMP+ where volunteers collect water chemistry and temperature profile data in addition to collecting Secchi disk readings. Under this program, water samples are collected twice monthly from May through September. The samples are sent off to a laboratory to identify the levels of chlorophyll-a and total phosphorus in the lake which determines the Trophic State Index. By verifying this relationship, the MPCA can continue to use Secchi depth readings as a reliable indicator of the nutrients and algal productivity in the lake.

At our September meeting, our LVA Board voted to apply to the MPCA to have Lake Vermilion included in the CLMP+ program. Since the MPCA provides all of the equipment, training, and laboratory costs, there are a limited number of lakes included in this advanced program each year. In early October, we were notified that Vermilion has been selected for the 2008 season. Samples will be collected from 8 sites, including the six existing DNR / MPCA long term stations in Wakemup Bay, Niles Bay, Big Bay, Frazer Bay, Pike Bay, and a location near Trout Lake portage.

Later in 2008, the MPCA will publish a CLMP+ report on Lake Vermilion. A sample report from another lake may be viewed at the above noted website. Jesse Anderson , MPCA Research Scientist will be at our November LVA Board meeting to discuss the planning, logistical support, and the training of volunteers for the 2008 program.

Volunteers are needed to staff this effort. A significant time commitment is required. Two teams of three, including a boat pilot, a sample collector and a data recorder, will spend a full day on the water twice a month from May through September. Those interested in helping with this 2008 project should contact Mel Hintz. Classroom and on-the-water team training is currently planned for May 6, 2008.

2008 Lake Vermilion CLMP+ Study

Mid-Summer Progress Report by Mel Hintz

Edited from an article in the August 2008 issue of The Vermilion Sportsman

clmpmap_e1hrIn early July, Vermilion Lake Association volunteers completed the first half of the collection, processing, and shipping of water samples from the eight sites selected for study as part of the state-sponsored Citizen Lake Monitoring Program Plus (CLMP+). A map showing the location of the eight sites is shown below and in the May issue of the Vermilion Lake Association newsletter. Samples were collected on June 2nd , June 23rd, and July 7th. The volunteers will get a break as staff from the Minnesota Pollution Control Agency (MPCA) will be collecting water samples from the eight sites during the third week of July. This allows them to check the accuracy of our work as well as to re-supply our three volunteer teams with the materials needed for the remainder of the season which has sampling dates scheduled for August 4th, August 18th, and September 2nd. MPCA staff will also be collecting the last set of samples for this season in late September.

For each of our three volunteer teams, the process of field collection, on shore processing, and delivery of the samples for shipment to the lab takes approximately four hours. Following is the sampling procedure for each site: 1) locate the site using GPS coordinates, 2) fill in the data and observation sheet, 3) note current weather conditions, the physical condition of the lake water, and the lake’s recreational suitability, 4) take a Secchi transparency reading, 5) record a temperature and dissolved oxygen profile from the lake surface to the bottom, and 6) collect water samples for laboratory analysis and/or on shore processing.

On shore processing consists of filtering the lake water to collect a chlorophyll-a sample and preserving an algae sample by adding Lugol’s solution. The MPCA provides specialized equipment and supplies used in the collection and processing of the water samples. The samples are refrigerated or frozen (in the case of the chlorophyll sample) before they are packed in ice and delivered to the DNR Office in Tower or the U.S. Forest Service Office in Cook for shipment to the lab the following day.

MPCA staff will analyze the laboratory results and prepare a written report after the sampling is completed in late September. Their report will be covered in a future issue of our newsletter and will be posted on this website.

Water Quality Monitoring – Recent Reports

MPCA’s Lake Assessment Program Report  [2000]

The Minnesota PCA describes its Lake Assessment Program (LAP) as a

(C)ooperative study of a lake involving MPCA staff and local citizens. LAP studies serve to characterize a lake’s condition and provide some basic information regarding the interaction of the lake and its watershed.

A comprehensive LAP study report on Lake Vermilion was published in 2000. It discusses watershed characteristics, reviews past studies and historical data, presents water quality trends, and makes recommendations for lake management. To read the full report, including its summary and recommendations, please click here.

An Elemental Analysis of Lake Sediment Core Samples  [2005]

During 2004, U.S. Steel was developing a proposal to discharge up to 7.2 million gallons per day from their Minntac tailings basin northward into the Dark River, a State designated trout stream, and the Sandy River, a tributary to Lake Vermilion. The major concern with the discharge into Lake Vermilion is that the high sulfate content in the tailings basin water could trigger increased mercury methylation leading to mercury accumulation in fish.

To capture baseline data on Lake Vermilion’s sediments and to understand the sensitivity of the lake to further inflows, the Vermilion Lake Association contacted Dr. Euan D. Reavie, Director of the Center for Water and the Environment, Natural Resources Research Institute, Univ of Minnesota Duluth. During the fall of 2004, Dr. Reavie took sediment core samples along the potential inflow path at three locations: the Pike River Flowage basin, the outlet of Pike Bay, and in Big Bay. He presented his analysis of these samples and his conclusions to the Vermilion Lake Association board in January 2005.

Dr. Reavie’s written report Lake Vermilion Elemental Paleoecology, dated 4/22/05, is available here. Detailed chemical analyses of sediments from the top and bottom of each core were performed. Bottom sediments reflect conditions prior to European settlement of the region, and top sediments reflect the current, non-pristine condition.

Comparison of bottom and top sediment revealed that local factors, such as watershed development, road salt application and other human activities, have been the dominant factors in changing Lake Vermilion’s ecology over the last 150 years. There was no detectable evidence that any seepage from Minntac’s tailings pond has had an effect on Lake Vermilion at the time of the study.

In early 2006, U.S. Steel revised their tailing pond discharge proposal. Under the revised plan, this water would now be pumped into the West Two Rivers Reservoir and subsequently released to flow south toward Lake Superior via the St. Louis River. This is good news for those concerned about Lake Vermilion water quality. However, U.S. Steel’s current proposal has not been fully approved and significant revisions are possible.

Read more on potential for tailings pond water discharge into Lake Vermilion’s watershed in the May 2006 issue of The Vermilion Sportsman.

Historical Lake Vermilion Water Quality Data

Secchi Disk Data

Historical Secchi transparency data, which date back to 1976, reveal a significant improvement in transparency based on 26 summers of data. During this 32-year period, the summer mean Secchi has improved from near 5 feet in the late 1970s to 8 feet in the late 1990’s. Mean values after 2000 have improved further to the 9-foot range.

The MPCA has compiled this historical Secchi data in an easy-to-read format here. While the data are from a single site in Big Bay near Pine Island, they are representative of the trends seen at other sites in Lake Vermilion.

Historical Secchi data from all monitoring sites in Lake Vermilion will be tabulated in the future.

Carlson Trophic State Index

The Minnesota PCA has developed an overall assessment of Lake Vermilion’s trophic status based on measurements of phosphorus and chlorophyll-a levels from the 2000 Lake Assessment Report and on recent Secchi disk data (see above). The Carlson Trophic State Indices computed from each of those methods are in close agreement, ranging from 46 to 51 (on a scale that ranges from 20 to 80). That places Lake Vermilion midway between the mesotrophic and eutrophic states.

For more detail on what the trophic state means and on the underlying data, click here.

For More Information on Water Quality Monitoring or to Volunteer

For more information on our overall water quality monitoring program or to volunteer to assist in this ongoing effort, please contact activity coordinator Mel Hintz.