National Lakes Assessment 2012

Transcription

1 National Lakes Assessment 2012 Lake Specific Reports: Lakes on the Red Lake Reservation This is part of a series based on Minnesota s participation in U.S. EPA s 2012 National Lakes Assessment November 2013

2 Minnesota s 2012 National Lakes Assessment was led by MPCA s Water Quality Monitoring Unit. A total of 150 lakes were sampled during summer 2012 in this effort. Team leads for the survey, which included responsibility for field reconnaissance, assembling and purchasing needed equipment, office logistics, and sampling of the lakes was led by Pam Anderson, Jesse Anderson, Kelly O Hara, Lee Engel, Dereck Richter, and Steve Heiskary. Other staff assisting with sampling included: Amy Garcia, Courtney Ahlers-Nelson, Mike Kennedy and Andrew Swanson. Student workers Will Long and Ben Larson also assisted with the sampling. In addition to MPCA staff, Minnesota Department of Natural Resources, US Forest Service, and Native American Band natural resources staff were instrumental in support of sampling and reconnaissance for many of the lakes in this survey. Report Author: Steven Heiskary Pictures on front cover are examples of lakes sampled in this 150-lake survey effort. Map of lakes included in Minnesota s 2012 National Lakes Assessment wq-nlap1-07

3 2012 National Lakes Assessment (NLA): Lake Specific Reports National Lakes Assessment (NLA) Overview Lakes on the Red Lake Reservation Minnesota routinely participates in the USEPA s national random surveys of lakes, streams, wetlands, and estuaries. These surveys occur on a rotating five-year basis. In the first NLA in 2007, Minnesota received 42 lakes as a part of the national draw and added 8 lakes to allow for state-based assessment. Several partnerships were established to help conduct the survey and prominent partners included Minnesota Departments of Natural Resources and Agriculture and the US Forest Service (Superior National Forest). With aid of these partners, there were several significant add-ons to the national study. In 2012, these same partners and collaborations with the Red Lake and White Earth Bands contributed to a successful survey of Minnesota s lakes. Notable add-ons in 2012 included pesticides, emerging contaminants, and zooplankton. This series of reports focuses on lakes that are within the Red Lake Reservation and were sampled during the 2012 NLA. Study design In the 2012 NLA, Minnesota received 42 lakes and added eight lakes from the overdraw pool to yield 50 lakes, which allows for statistically based condition estimates for Minnesota s lakes. All 50 lakes followed the national protocols that included water chemistry, algae, zooplankton and sediment core collection, and physical-habitat assessment. Further details are available at the USEPA site In addition, MPCA added 100 lakes from the overdraw list, to allow for ecoregion-based assessments for the three aggregated ecoregions that comprise Minnesota: Northern Forests (NLF & NMW), Eastern Temperate Forests (CHF & DA), and Great Plains (WCBP, NGP, & RRV). Water chemistry, dissolved oxygen and temperature profiles, Secchi, blue-green algal toxin microcystin, pesticide triazine assay, and zooplankton samples were collected from each of these lakes. This 150-lake frame provides comprehensive and representative coverage of Minnesota lakes. Lake-specific reports While the primary emphasis of the NLA is to statistically-describe the condition of lakes at national, regional, and state scales, the MPCA provides lake-specific reports for a subset of the 2012 NLA lakes. These reports serve a variety of purposes as follows: Response to request from landowners or other entities that have provided access to lakes and are interested in learning more about the lake. Provided for lakes within reservation boundaries, forest service property, or other areas where collaborators may be interested in NLA results. 1

4 Provided for all 2007 NLA lakes re-sampled in the 2012 survey. These reports will compare results among the two surveys and allow for observations on trends. The individual reports include summary statistics on lake morphometry, watershed area, and land use composition (2006 NLCD). Basic water chemistry and comparisons to ecoregion norms and water quality standards are made when appropriate. A brief narrative is provided for each lake as well. These reports generally do not include biological data, sediment core, nearshore assessments, pesticides, or emerging contaminant information as these will be addressed in topic specific reports that will be posted at Background 2012 National Lakes Assessment (NLA): Lake Specific Report for Miskogineu Lake MN-206 ( ) Miskogineu Lake is a moderate sized, but very shallow lake located in Clearwater County, immediately west of Red Lake. It is located on Red Lake Reservation and is part of a large wetland/bog complex. It is several miles from the nearest road and required assistance from the Red Lake DNR Water Resources Program to access the lake with their Argo ATV. The lake is accessed periodically by the Band for natural resources work; however, it is not visited on a routine basis by anyone. It has a moderate watershed relative to its surface area (13:1) and land use is dominated by water and wetlands, which is not typical for lakes in the Northern Lakes and Forests ecoregion but is fairly typical of lakes in the Northern Minnesota Wetlands Ecoregion. The entire lake is considered littoral and submergent and emergent plants (including wild rice) were evident throughout the lake. Summary data, watershed map, and graphics are included in the following pages. Results and Discussion The trophic status parameters: TP, chlorophyll-a, and Secchi are indicative of oligotrophic to mesotrophic status. Secchi was visible on the bottom of the lake. These measures are all within or below the typical range for the NLF ecoregion. These measures are also well within the water quality standards for NLF lakes as well. Total Kjeldahl nitrogen was just above the typical range. The water is moderately colored based on the color and dissolved organic carbon values and reflects inputs from the surrounding bog/wetland complex. The alkalinity, conductivity, calcium, and magnesium values indicate moderately hard water. Sulfate and chloride (Cl) levels are very low, which suggests no immediate anthropogenic sources of Cl enter the lake. The amount of algae was fairly low, based on chlorophyll-a. The blue-green algal toxin, microcystin, was below the reporting limit in at the mid-lake sites and just above the RL at a random nearshore site. These are very low and present no risk. Samples were also collected for measurement of various emerging contaminants (EMC) and pesticides. Of the numerous EMC tested for, only two contaminants were detected: DEET (a personal care product) 2

5 and Androstenedione (a hormone). Further details on this study and information on these contaminants may be found in In summary, Miskogineau is a very remote and pristine lake. It is large relative to the overall population of lakes in the aggregated Northern Forests ecoregion, ranking above the 80 th percentile. However, it is very shallow and can be considered to be in a clear water phase that is characterized by abundant submerged and emergent macrophytes. 3

6 National Lakes Assessment 2012 Miskogineu Lake, Clearwater County (DOW , NLA12_MN 206) Lake and Watershed Characteristics Lake Metric English Lake Area 49 hectares 121 acres Lake Maximum depth 1.8 meters 6 feet Lake Mean depth 1.0 meters 3.3 feet Watershed area (total) 634 hectares 1,567 acres Watershed: lake ratio 13:1 Ecoregion: Northern Minnesota Wetlands (NMW) Land use Lake % NLF Typical Land Use % Developed Cultivated (Ag) 0 <1 Pasture & Open Forest Water & Wetland

7 Miskogineu Lake 2012 NLA visit as compared to typical range for NLF ecoregion reference lakes and water quality standards (WQS). Ecoregion range and standards are based on summer-mean values. Parameter 2012 NLF WQS Date 6/26/2012 Temperature C 24.2 Total Phosphorus (µg/l) < 30 Chlorophyll (µg/l) <9.0 Secchi Disk (meters) > >2.0 Total Kjeldahl Nitrogen (mg/l) Total Nitrogen (mg/l) Color (Pt-Co Units) Dissolved organic carbon (mg/l) 18.9 ph (SU) Total Suspended Sol. (mg/l) 4.4 < 1 2 Conductivity (umhos/cm) Alkalinity (mg/l) Calcium (mg/l) 21.7 Magnesium (mg/l) 9.9 Sulfate (mg/l) 1.0 Chloride (mg/l) < Microcystin (µg/l) mid, nearshore WHO Risk Category 1 < <0.15 RL, <10 Low Mod. Risk High Risk 1 Guidelines for safe recreational water environments (World Health Organization, 2003) & MDH report limit 5

8 2012 National Lakes Assessment (NLA): Lake Specific Report for Fox Lake MN-334 (4-0251) Background Fox Lake is a small lake with moderate depth located in Beltrami County, immediately south of Red Lake. It is located on Red Lake Reservation and is readily accessible from an adjacent road. Red Lake DNR Water Resources Program staff assisted in the sampling of this lake. It has a small watershed relative to its surface area (6:1) and land use is dominated by forest and wetlands, which is typical for lakes in the Northern Lakes and Forests ecoregion. Summary data, watershed map, and graphics are included in the following pages. Results and Discussion Fox Lake was stratified on the June 26, 2012 sample date. The thermocline formed between 2-4 meters and dissolved oxygen was too low to support fish below 4 meters. The trophic status parameters: TP, chlorophyll-a, and Secchi are indicative of oligotrophic to mesotrophic status. These measures are all within or below the typical range for the NLF ecoregion. These measures are also well within the water quality standards for NLF lakes as well. Total Kjeldahl nitrogen was just above the typical range. The water is clear based on the color and dissolved organic carbon values. The alkalinity, conductivity, calcium, and magnesium values indicate moderately hard water. Sulfate and chloride (Cl) levels are very low, which suggests no immediate anthropogenic sources of Cl enter the lake. The amount of algae was very low, based on chlorophyll-a. The blue-green algal toxin, microcystin, was below the reporting limit at the mid-lake site. This level presents no human health risk. In summary, while Fox Lake is relatively small, it s surface area does rank near the 70 th percentile for lakes in the aggregated Northern Forests Ecoregion. Its water quality is comparable to the NLF ecoregion reference lakes and it would meet applicable lake eutrophication standards based on the NLA data. 6

9 National Lakes Assessment 2012 Fox Lake Beltrami County (DOW , NLA12_MN-334) Lake and Watershed Characteristics Lake Metric English Lake Area 15 hectares 37 acres Lake Maximum depth 6.1 meters 20 feet Lake Mean depth NA NA Watershed area (total) 91 hectares 224 acres Watershed: lake ratio 6: 1 Land use composition for total watershed including the lake, based on 2006 NLCD. Land use Fox Lake % NLF Typical Land Use % Developed Cultivated (Ag) 0 <1 Pasture & Open Forest Water & Wetland

10 Fox Lake 2012 NLA visit as compared to typical range for NLF ecoregion reference lakes and water quality standards (WQS). Ecoregion range and standards are based on summer-mean values. Parameter 2012 NLF WQS Date 6/26/2012 Temperature C 23.9 Total Phosphorus (µg/l) Chlorophyll (µg/l) Secchi Disk (meters) Total Kjeldahl Nitrogen (mg/l) Total Nitrogen (mg/l) Color (Pt-Co Units) Dissolved organic carbon (mg/l) 11.9 ph (SU) Total Suspended Sol. (mg/l) 1.6 < 1 2 Conductivity (µmhos/cm) Alkalinity (mg/l) Calcium (mg/l) 37.2 Magnesium (mg/l) 20.6 Sulfate (mg/l) <2.0 Chloride (mg/l) < Microcystin (µg/l) <0.15 <0.15 RL, <10 Low Risk WHO Risk Category Mod. Risk High Risk 1 Guidelines for safe recreational water environments (World Health Organization, 2003) & MDH report limit Dissolved oxygen and temperature profile for