Kitchi Lake 04-0007-00 -BELTRAMI COUNTY
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Kitchi Lake 04-0007-00 -BELTRAMI COUNTY Lake Water Quality Summary Kitchi Lake is located 14 miles north of Cass Lake, MN in Beltrami County. It is an irregular shaped lake covering 1,826 acres with a maximum depth of 57 feet (Table 1). Kitchi Lake has two inlets and one outlet, which classify it as a drainage lake (Figure 1). The west side of the lake receives drainage from Little Rice Lake via the Turtle River and the east side receives drainage from Kitchi Creek. The large middle bay on the south end contains the outlet. Water flows out of Kitchi Lake via the Turtle River and into Pug Hole and Cass Lakes. Water quality data have been collected on Kitchi Lake in 1991 and 2004-2005 (Tables 2-3). These data show that the lake is mesotrophic, which is characteristic of moderately clear water throughout the summer and excellent recreational opportunities (page 6). Currently, Kitchi Lake has no organized lake association. Table 1. Kitchi Lake location and key physical characteristics. Location Data Physical Characteristics MN Lake ID: 04-0007-00 Surface area (acres): 1826 County: Beltrami Littoral area (acres): 953 Ecoregion: Northern Lakes and Forest % Littoral area: 52% Major Drainage Basin: Upper Mississippi River Max depth (ft), (m): 57, 17.4 Latitude/Longitude: 47.499978, -94.510574 Inlets: 2 Invasive Species: None as of 2011 Outlets: 1 Public Accesses: 3 Table 2. Availability of primary data types for Kitchi Lake. Data Availability Only two years of transparency exist for this lake. Transparency data Transparency should be monitored yearly to track water quality trends. Chemical data No phosphorus or chlorophyll a data exist for this lake. Inlet/Outlet data No inlet or outlet data exist for this lake. Recommendations For recommendations refer to page 16. RMB Environmental Laboratories, Inc. 1 of 18 2011 Kitchi Lake Lake Map Figure 1. Map of Kitchi Lake with 2010 aerial imagery and illustrations of lake depth contour lines, sample site locations, inlets and outlets, and public access points. The light green areas in the lake illustrate the littoral zone, where the sunlight can usually reach the lake bottom allowing aquatic plants to grow. Table 3. Monitoring programs and associated monitoring sites. Programs include the Citizens Lake Monitoring Program (CLMP) and the Minnesota Pollution Control Agency (MPCA). Lake Site Depth (ft) Monitoring Programs 201 22 CLMP: 2004-2005 100 24 MPCA: 1991 RMB Environmental Laboratories, Inc. 2 of 18 2011 Kitchi Lake Water Quality Characteristics - Historical Means and Ranges Table 4. Water quality means and ranges for primary sites. Primary Parameters Site 201 Total Phosphorus Mean (ug/L): Total Phosphorus Min: Total Phosphorus Max: Number of Observations: Chlorophyll a Mean (ug/L): Chlorophyll-a Min: Chlorophyll-a Max: Number of Observations: Secchi Depth Mean (ft): 10.2 Secchi Depth Min: 6.0 Secchi Depth Max: 17.0 Number of Observations: 6 Figure 2. Kitchi Lake total phosphorus, chlorophyll a and transparency historical ranges. The arrow represents the range and the black dot represents the historical mean (Primary Site 201). Figure adapted after Moore and Thornton, [Ed.]. 1988. Lake and Reservoir Restoration Guidance Manual. (Doc. No. EPA 440/5-88-002) RMB Environmental Laboratories, Inc. 3 of 18 2011 Kitchi Lake Transparency (Secchi Depth) Transparency is how easily light can pass through a substance. In lakes it is how deep sunlight penetrates through the water. Plants and algae need sunlight to grow, so they are only able to grow in areas of lakes where the sun penetrates. Water transparency depends on the amount of particles in the water. An increase in particulates results in a decrease in transparency. The transparency varies year to year due to changes in weather, precipitation, lake use, flooding, temperature, lake levels, etc. The annual mean transparency was 11 feet in 2004 and 9 feet in 2005. Over these two years, the transparency ranged from 6 to 17 feet. Figure 3 shows the seasonal transparency dynamics. Kitchi Lake transparency is lower in early May as the lake is turning over. The maximum Secchi reading is usually obtained in early summer. The transparency then declines in August. If Secchi readings were taken through October, the transparency would likely rebound after fall turnover. This transparency dynamic is typical of a northern Minnesota lake. The dynamics have to do with algae and zooplankton population dynamics, and lake turnover. It is important for lake residents to understand the seasonal transparency dynamics in their lake sp that they are not worried about why their transparency is lower in August than it is in June. It is typical for a lake to vary in transparency throughout the summer. Seasonal Transparency Dynamics 18.0 16.0 14.0 12.0 (ft) 2004 10.0 2005 Depth 8.0 pattern Secchi 6.0 Poly. (pattern) 4.0 2.0 0.0 Figure 3. Seasonal transparency dynamics and year to year comparison (Primary Site 201). The black line represents the pattern in the data. RMB Environmental Laboratories, Inc. 4 of 18 2011 Kitchi Lake Total Phosphorus and Chlorophyll a There is no phosphorus or chlorophyll a data for Kitchi Lake. Two years of data would give a good indication of the lake’s condition and enable Minnesota Pollution Control Agency Assessment. Dissolved Oxygen Dissolved Oxygen (DO) is the amount of oxygen dissolved in lake water. Oxygen is necessary for all living organisms to survive except for some bacteria. Living organisms breathe in oxygen that is dissolved in the water. Dissolved oxygen levels of <5 mg/L are typically avoided by game fisheries. Dissolved Oxygen (mg/L) Kitchi Lake’s main bay is shallow, but the long western bay is deep, with a maximum depth of 57 feet. 0 5 10 15 Dissolved oxygen profiles from 8/14/91 indicate that 0 the deep areas of the lake stratify in the summer (Figure 4). The thermocline in August of 1991 was 2 around 5 meters (16 feet), which means that game fish would not be present deeper than 16 feet. 4 The main shallow bay of Kitchi Lake mostly acts differently than the deep western bay. Because it is 25 6 feet deep or less, one would expect that the water column would never completely stratify. The lake 8 most likely mixes every time there is a large (m) storm/wind event. 8/14/1991 10 Depth 12 Figure 4. Dissolved oxygen and temperature profile for Kitchi Lake in 1991. 14 16 18 20 RMB Environmental Laboratories, Inc. 5 of 18 2011 Kitchi Lake Trophic State Index Table 5. Trophic State for Kitchi Lake. Phosphorus (nutrients), chlorophyll a (algae Trophic State Index Site 205 concentration) and Secchi depth (transparency) are related. As phosphorus increases, there is more food TSI Total Phosphorus NA available for algae, resulting in increased algal TSI Chlorophyll-a NA concentrations. When algal concentrations increase, TSI Secchi 42 the water becomes less transparent and the Secchi TSI Mean NA depth decreases. Trophic State: Mesotrophic Numbers represent the mean TSI for each The results from these three measurements cover parameter. different units and ranges and thus cannot be directly compared to each other or averaged. In order to standardize these three measurements to make them 100 directly comparable, we convert them to a trophic state index (TSI). Hypereutrophic The TSI for Kitchi Lake transparency is in the 70 mesotrophic range (Figure 5). There is no phosphorus Eutrophic or chlorophyll a data to calculate those TSIs. Mesotrophic lakes (TSI 40-50) are 50 characterized by moderately clear water Kitchi Lake Mesotrophic most of the summer (Table 6). “Meso” 40 means middle or mid; therefore, mesotrophic means a medium amount of productivity. Mesotrophic lakes are commonly found in central Minnesota and have clear water with algal blooms in late Oligotrophic summer. They are also good for walleye fishing. 0 Figure 5. Trophic state index chart with corresponding trophic status. Table 6. Trophic state index attributes and their corresponding fisheries and recreation characteristics. TSI Attributes Fisheries & Recreation <30 Oligotrophy: Clear water, oxygen throughout Trout fisheries dominate the year at the bottom of the lake, very deep cold water. 30-40 Bottom of shallower lakes may become anoxic Trout fisheries in deep lakes only. Walleye, (no oxygen). Cisco present. 40-50 Mesotrophy: Water moderately clear most of No oxygen at the bottom of the lake results in the summer. May be "greener" in late summer. loss of trout. Walleye may predominate. 50-60 Eutrophy: Algae and aquatic plant problems Warm-water fisheries only. Bass may possible. "Green" water most of the year. dominate. 60-70 Blue-green algae dominate, algal scums and Dense algae and aquatic plants. Low water aquatic plant problems. clarity may discourage swimming and boating. 70-80 Hypereutrophy: Dense algae and aquatic Water is not suitable for recreation. plants. >80 Algal scums, few aquatic plants Rough fish (carp) dominate; summer fish kills possible Source: Carlson, R.E. 1997. A trophic state index for lakes. Limnology and Oceanography. 22:361-369. RMB Environmental Laboratories, Inc. 6 of 18 2011 Kitchi Lake Trend Analysis For detecting trends, a minimum of 8-10 years of data with 4 or more readings per season are recommended. Minimum confidence accepted by the MPCA is 90%. This means that there is a 90% chance that the data are showing a true trend and a 10% chance that the trend is a random result of the data. Only short-term trends can be determined with just a few years of data, because there can be different wet years and dry years, water levels, weather, etc, that affect the water quality naturally. There is not enough historical data to perform trend analysis for transparency, total phosphorus or chlorophyll a on Kitchi Lake.