Lower Hay Lake CROW WING COUNTY

Transcription

1 Lower Hay Lake CROW WING COUNTY Lake Water Quality Summary Lower Hay Lake is located 2 miles northeast of Jenkins, MN in Crow Wing County. It has a rounded shape and covers 693 acres. Lower Hay Lake has one inlet and one outlet, which classify it as a drainage lake. This lake is located at the top of the Whitefish chain of lakes. Hay Creeks enters the lake along the southeast shoreline. The outlet is a navigable connection to Upper Whitefish Lake. Water quality data have been collected on Lower Hay Lake in 1981, , and (Table 3). These data show that the lake is in the mesotrophic range (TSI=43), which is characteristic of clear water throughout most of the summer and excellent recreational opportunities (page 9). The Friends of Lower Hay Lake Association are dedicated to protecting the water and watershed of Lower Hay Lake and the preservation of surrounding natural resources through sharing of information with other organizations. The Association meets several times a year. Table 1: Lower Hay Lake location and key physical characteristics. Location Data MN Lake ID: County: Crow Wing Ecoregion: Northern Lakes & Forests Major Drainage Basin: Pine River Watershed Latitude/Longitude: , Invasive Species: None as of 211 Physical Characteristics Surface area (acres): 693 Littoral area (acres): 159 % Littoral area: 23% Max depth (ft), (m): 1, 3 Inlets: 1 Outlets: 1 Public Accesses: 1 Table 2: Availability of data and an observation of the quantity of sample points. Data Availability Transparency data Chemical data Excellent data set from the Citizen Lake Monitoring Program. Several sites have data from the 198s to the present. Site 25 has phosphorus and chlorophyll a data from and This a good set of data, but not enough to run trends. Inlet/Outlet data No inlet or outlet data is available. Recommendations For recommendations refer to page 18. RMB Environmental Laboratories, Inc. 1 of Lower Hay Lake

2 Lake Map Figure 1. Map of Lower Hay Lake illustrating bathymetry, lake sample site locations, stream inlets and outlets and 21 aerial land use. The light green shaded 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 Minnesota Pollution Control Agency (MPCA), Citizens Lake Monitoring Program (CLMP), and Whitefish Area Property Owners Association (WAPOA). Lake Site Depth Monitoring Programs (ft) 1 9 MPCA: CLMP: , 1991, CLMP: 1988, ; WAPOA: CLMP: *primary site 9 CLMP: ; MPCA: WAPOA: 1981, , , RMB Environmental Laboratories, Inc. 2 of Lower Hay Lake

3 Average Water Quality Statistics The information below describes available chemical data for the primary site (25) of Lower Hay Lake through 29 (Table 4). The data set is limited, and all parameters with the exception of total phosphorus, chlorophyll a and secchi depth, are means for just 1981 data. Minnesota is divided into 7 ecoregions based on land use, vegetation, precipitation and geology. The MPCA has developed a way to determine the "average range" of water quality expected for lakes in each ecoregion. For more information on ecoregions and expected water quality ranges, see page 9. Table 4. Water quality means compared to ecoregion ranges and impaired waters standard. Impaired Parameter Mean Ecoregion Range 1 Waters Standard 2 Interpretation Total phosphorus (ug/l) > 3 3 Chlorophyll a (ug/l) > 6 Chlorophyll a max (ug/l) 11 <15 Secchi depth (ft) < 6.5 Dissolved oxygen Dimictic See page 8 Results are within the expected range for the ecoregion. Dissolved oxygen depth profiles show that the deep areas of the lake are anoxic in late summer. Total Kjeldahl Nitrogen Indicates insufficient nitrogen to support summer nitrogeninduced algae blooms. (mg/l) Alkalinity (mg/l) Indicates a low sensitivity to acid rain and a good buffering capacity. Color (Pt-Co Units) Indicates clear water with little to no tannins (brown stain). ph Indicates a hardwater lake. Lake water ph less than 6.5 can affect fish spawning and the solubility of metals in the water. Chloride (mg/l) NA Data not available. Total Suspended Solids (mg/l) NA <1-2 Data not available. Conductivity (umhos/cm) Within the expected range for the ecoregion. Total Nitrogen :Total Phosphorus 26:1 25:1 35:1 Indicates the lake is phosphorus limited, which means that algae growth is limited by the amount of phosphorus in the lake. 1 The ecoregion range is the 25 th -75 th percentile of summer means from ecoregion reference lakes 2 For further information regarding the Impaired Waters Assessment program, refer to 3 Chlorophyll a measurements have been corrected for pheophytin Units: 1 mg/l (ppm) = 1, ug/l (ppb) RMB Environmental Laboratories, Inc. 3 of Lower Hay Lake

4 Water Quality Characteristics - Historical Means and Ranges Table 5. Water quality means and ranges for primary sites. Parameters Site 25 Site 22 Site 21 Total Phosphorus Mean (ug/l): Total Phosphorus Min: 9 5 Total Phosphorus Max: Number of Observations: 3 5 Chlorophyll a Mean (ug/l): 4 3 Chlorophyll-a Min: <1 1 Chlorophyll-a Max: 11 4 Number of Observations: 3 5 Secchi Depth Mean (ft): Secchi Depth Min: Secchi Depth Max: Number of Observations: Figure 2. Lower Hay Lake total phosphorus, chlorophyll a and transparency historical ranges. The arrow represents the range and the black dot represents the historical mean (Site 25). Figure adapted after Moore and Thornton, [Ed.] Lake and Reservoir Restoration Guidance Manual. (Doc. No. EPA 44/5-88-2) RMB Environmental Laboratories, Inc. 4 of Lower Hay Lake

5 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 ranges from 9.3 to 18.7 feet. With the exception of 1989 and 24 data, the annual means stay relatively close to the long-term mean. The transparency throughout the lake appears to be relatively uniform, with the best transparency occurring at the deeper spots in the lake (sites 21 and 22). The transparency appears to hover around the mean showing year-to-year variability. The transparency has been better than the long-term average since 28. Transparency monitoring should be continued annually in order to track water quality changes. Secchi Depth (ft) Transparency: Annual Means Site 21 Site 22 Site 25 Longterm Mean, site 25 Figure 3. Annual mean transparency compared to long-term mean transparency. Lower Hay Lake transparency ranges from 8.5 to 19 feet at site 25. Figure 4 shows the seasonal transparency dynamics. The maximum Secchi reading is usually obtained in early summer. Lower Hay Lake transparency is high in May and June, and then declines slightly through August. It then rebounds in October after fall turnover. 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 so 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. RMB Environmental Laboratories, Inc. 5 of Lower Hay Lake

6 Secchi Depth (ft) Seasonal Transparency Dynamics pattern Poly. (pattern) Figure 4. Seasonal transparency dynamics and year to year comparison (Primary Site 25). The black line represents the pattern in the data. User Perceptions When volunteers collect secchi depth readings, they record their perceptions of the water based on the physical appearance and the recreational suitability. These perceptions can be compared to water quality parameters to see how the lake "user" would experience the lake at that time. Looking at transparency data, as the secchi depth decreases the perception of the lake's physical appearance rating decreases. Lower Hay Lake was rated as being "crystal clear" 4% of the time between (site 25). Physical Appearance Rating 3% 4% Crystal clear water 57% Not quite crystal clear a little algae visible 4% 3% Definite algae green, yellow, or brown color apparent 57% % High algae levels with limited clarity and/or mild odor apparent % Severely high algae levels Figure 5. Physical appearance rating, as rated by the volunteer monitor (23-29). RMB Environmental Laboratories, Inc. 6 of Lower Hay Lake

7 As the secchi depth decreases, the perception of recreational suitability of the lake decreases. Lower Hay Lake was rated as being "beautiful" 63% of the time from (site 25). Recreational Suitability Rating 37% 63% Beautiful, could not be better 37% Very minor aesthetic problems; excellent for swimming, boating 63% % Swimming and aesthetic enjoyment of the lake slightly impaired because of algae levels % Desire to swim and level of enjoyment of the lake substantially reduced because of algae levels % Swimming and aesthetic enjoyment of the lake nearly impossible because of algae levels Figure 6. Recreational suitability rating, as rated by the volunteer monitor (23-29). Total Phosphorus Lower Hay Lake is phosphorus limited, which means that algae and aquatic plant growth is dependent upon available phosphorus. Total phosphorus was evaluated in Lower Hay Lake in 23-25, The data do not indicate much seasonal variability. Both sites have similar phosphorus concentrations (Figure 7). The majority of the data points fall into the mesotrophic range. Total Phosphorus (ug/l) Phosphorus should continue to be monitored to track any future changes in water quality Total Phosphorus Mesotrophic Oligotrophic Site 25, 23 Site 25, 24 Site 25, 25 Site 25, 27 Site 25, 28 Site 25, 29 Site 22, 21 Figure 7. Historical total phosphorus concentrations (ug/l) for Lower Hay Lake. RMB Environmental Laboratories, Inc. 7 of Lower Hay Lake

8 Chlorophyll a Chlorophyll a is the pigment that makes plants and algae green. Chlorophyll a is tested in lakes to determine the algae concentration or how "green" the water is. Chlorophyll a concentrations greater than 1 ug/l are perceived as a mild algae bloom, while concentrations greater than 2 ug/l are perceived as a nuisance. Chlorophyll a (ug/l) Chlorophyll a Site 25, 23 Site 25, 24 Site 25, 25 Site 25, 27 Site 25, 28 Site 25, 29 Site 22, 21 Minor Algae Chlorophyll a was Figure 8. Chlorophyll a concentrations (ug/l) for Lower Hay Lake. evaluated in Lower Hay Lake in 23-25, Chlorophyll a concentrations remained below 1 ug/l for all but one sample date, indicating clear water most of the summer (Figure 8). There was not much variation between sites or years monitored, and chlorophyll a concentrations remained relatively steady over the summer. Dissolved Oxygen Depth (m) Dissolved Oxygen (mg/l) 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. Lower Hay Lake is a deep lake, with a maximum depth of 1 feet. Dissolved oxygen profiles from 22 at site 25 (6 feet deep) indicate that the lake stratifies in the summer. The thermocline appears to reside at approximately 8 meters (26 feet). The oxygen stays above 5 mg/l all summer until mid- August, when it still stays above 3 mg/l. In lakes this deep with low productivity, the oxygen can remain at good levels in the water column. These conditions are excellent habitat for Cisco fish, and Lower Hay Lake has been designated as a Cisco refuge lake by the MN DNR /7/22 7/16/22 8/14/22 9/9/22 Figure 9. Dissolved oxygen profile for Lower Hay Lake in 22 at site 25. RMB Environmental Laboratories, Inc. 8 of Lower Hay Lake

9 Trophic State Index Phosphorus (nutrients), chlorophyll a (algae concentration) and Secchi depth (transparency) are related. As phosphorus increases, there is more food available for algae, resulting in increased algal concentrations. When algal concentrations increase, the water becomes less transparent and the Secchi depth decreases. The results from these three measurements cover 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 directly comparable, we convert them to a trophic state index (TSI). The mean TSI for Lower Hay Lake falls into the mesotrophic range (Figure 1). There is good agreement between the TSI for phosphorus, chlorophyll a and transparency, indicating that these variables are strongly related Lower Hay Lake (Table 6). Mesotrophic lakes (TSI 4-5) are characterized by moderately clear water most of the summer (Table 7). "Meso" 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 summer. They are also good for walleye fishing. Table 6. Trophic State Index for Lower Hay Lake. Trophic State Index Site 25 TSI Total Phosphorus 44 TSI Chlorophyll-a 44 TSI Secchi 41 TSI Mean 43 Trophic State: Mesotrophic Numbers represent the mean TSI for each parameter. Hypereutrophic Eutrophic Mesotrophic Oligotrophic Figure 1. Trophic state index chart with corresponding trophic status. Table 7. Trophic State Index categories and corresponding lake conditions. TSI Attributes Fisheries & Recreation <3 Oligotrophy: Clear water, oxygen throughout Trout fisheries dominate the year at the bottom of the lake, very deep cold water. 3-4 Bottom of shallower lakes may become anoxic (no oxygen). Trout fisheries in deep lakes only. Walleye, Cisco present. 4-5 Mesotrophy: Water moderately clear most of the summer. May be "greener" in late summer. No oxygen at the bottom of the lake results in loss of trout. Walleye may predominate. 5-6 Eutrophy: Algae and aquatic plant problems possible. "Green" water most of the year. Warm-water fisheries only. Bass may dominate. 6-7 Blue-green algae dominate, algal scums and aquatic plant problems. Dense algae and aquatic plants. Low water clarity may discourage swimming and boating. 7-8 Hypereutrophy: Dense algae and aquatic Water is not suitable for recreation. plants. >8 Algal scums, few aquatic plants Rough fish (carp) dominate; summer fish kills possible Source: Carlson, R.E A trophic state index for lakes. Limnology and Oceanography. 22: RMB Environmental Laboratories, Inc. 9 of Lower Hay Lake

10 Trend Analysis For detecting trends, a minimum of 8-1 years of data with 4 or more readings per season are recommended. Minimum confidence accepted by the MPCA is 9%. This means that there is a 9% chance that the data are showing a true trend and a 1% 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 total phosphorus or chlorophyll a on Lower Hay Lake. Sites 25 had over 8 years of transparency data, which was enough data to perform a long-term trend analysis (Table 8). The data was analyzed using the Mann Kendall Trend Analysis. Table 8. Trend analysis for Lower Hay Lake. Lake Site Parameter Date Range Trend 25 Transparency , , No trend 25 Total Phosphorus 23-25, Insufficient data 25 Chlorophyll a 23-25, Insufficient data 21 Transparency , 1991, No trend 22 Transparency No trend 23 Transparency No trend 24 Transparency No trend Secchi Depth (ft) Transparency Trend for Lower Hay Lake Figure 11. Transparency (ft) trend for site 25. All sites for Lower Hay Lake show no trend in transparency. This means the transparency is stable (Figure 11). Transparency monitoring should continue so that this trend can be tracked in future years. RMB Environmental Laboratories, Inc. 1 of Lower Hay Lake

11 Ecoregion Comparisons Minnesota is divided into 7 ecoregions based on land use, vegetation, precipitation and geology (Figure 12). The MPCA has developed a way to determine the "average range" of water quality expected for lakes in each ecoregion. From , the MPCA evaluated the lake water quality for reference lakes. These reference lakes are not considered pristine, but are considered to have little human impact and therefore are representative of the typical lakes within the ecoregion. The "average range" refers to the 25 th - 75 th percentile range for data within each ecoregion. For the purpose of this graphical representation, the means of the reference lake data sets were used. Lower Hay Lake is in the Northern Lakes and Forests Ecoregion. The mean total phosphorus, chlorophyll a and transparency (secchi depth) for Lower Hay are all within the expected ecoregion ranges (Figure 13). Figure 12. Minnesota Ecoregions. 6 3 Total Phosphorus (ug/l, ppb) Chlorophyll-a (ug/l, ppb) Secchi depth (ft) increased algae crystal clear NLF Ecoregion Lower Hay NLF Ecoregion Lower Hay 25 NLF Ecoregion Lower Hay Figures 13a-c. Lower Hay Lake ranges compared to Northern Lakes and Forest Ecoregion ranges. The Lower Hay Lake total phosphorus and chlorophyll a ranges are from 3 data points collected in May-September of 23-25, The Lower Hay Lake Secchi depth range is from 11 data points collected in May- September from , , RMB Environmental Laboratories, Inc. 11 of Lower Hay Lake

12 Lakeshed Data and Interpretations Lakeshed Understanding a lakeshed requires an understanding of basic hydrology. A watershed is defined as all land and water surface area that contribute excess water to a defined point. The MN DNR has delineated three basic scales of watersheds (from large to small): 1) basins, 2) major watersheds, and 3) minor watersheds. The Pine River Major Watershed is one of the watersheds that make up the Upper Mississippi River Basin, which drains south to the Gulf of Mexico (Figure 14). This major watershed is made up of 69 minor watersheds. Lower Hay Lake is located in minor watershed 1147 (Figure 15). Figure 14. Pine River Major Watershed. Figure 15. Minor Watershed 1147 The MN DNR also has evaluated catchments for each individual lake with greater than 1 acres surface area. These lakesheds (catchments) are the building blocks for the larger scale watersheds. Lower Hay Lake falls within the Lower Hay (1147) lakeshed (Figure 16). Though very useful for displaying the land and water that contribute directly to a lake, lakesheds are not always true watersheds because they may not show the water flowing into a lake from upstream streams or rivers. While some lakes may have only one or two upstream lakesheds draining into them, others may be connected to a large number of lakesheds, reflecting a larger drainage area via stream or river networks. For further discussion of Lower Hay Lake s full watershed, containing all the upstream lakesheds, see page 17. The data interpretation of the Lower Hay Lake lakeshed includes only the immediate lakeshed, as this Figure 16. The Lower Hay Lake lakeshed (1147). RMB Environmental Laboratories, Inc. 12 of Lower Hay Lake

13 area is the land surface that flows directly into Lower Hay Lake. The lakeshed vitals table identifies where to focus organizational and management efforts for each lake (Table 9). Criteria were developed using limnological concepts to determine the effect to lake water quality. KEY Possibly detrimental to the lake Warrants attention Beneficial to the lake Table 9. Lower Hay Lake lakeshed vitals table. Lakeshed Vitals Rating Lake Area 693 acres descriptive Littoral Zone Area 159 acres descriptive Lake Max Depth 1 ft. descriptive Lake Mean Depth 49 ft. Water Residence Time NA NA Miles of Stream 2.1 descriptive Inlets 1 Outlets 1 Major Watershed 11 Pine River descriptive Minor Watershed 1147 descriptive Lakeshed 1147 descriptive Ecoregion Northern Lakes and Forest descriptive Total Lakeshed to Lake Area Ratio (total lakeshed includes lake area) 4:1 Standard Watershed to Lake Basin Ratio (standard watershed includes lake areas) 26:1 Wetland Coverage 9.1% Aquatic Invasive Species Public Drainage Ditches Public Lake Accesses 1 None None Miles of Shoreline 4.1 descriptive Shoreline Development Index 1.1 Public Land to Private Land Ratio.3:1 Development Classification General Development Miles of Road 11.3 descriptive Municipalities in lakeshed Forestry Practices Feedlots Sewage Management Lake Management Plan Lake Vegetation Survey/Plan Pequot Lakes County Forest Management: None Individual Subsurface Sewage Treatment Systems (Inspection and assessment required for all permits and property transfers within the Shoreland Protection Zone) Healthy Lakes & Rivers Partnership program, 28 None RMB Environmental Laboratories, Inc. 13 of Lower Hay Lake

14 Land Cover / Land Use The activities that occur on the land within the lakeshed can greatly impact a lake. Land use planning helps ensure the use of land resources in an organized fashion so that the needs of the present and future generations can be best addressed. The basic purpose of land use planning is to ensure that each area of land will be used in a manner that provides maximum social benefits without degradation of the land resource. Changes in land use, and ultimately land cover, impact the hydrology of a lakeshed. Land cover is also directly related to the lands ability to absorb and store water rather than cause it to flow overland (gathering nutrients and sediment Figure 17. The Lower Hay (1147) lakeshed land cover ( as it moves) towards the lowest point, typically the lake. Impervious intensity describes the lands inability to absorb water, the higher the % impervious intensity the more area that water cannot penetrate in to the soils. Monitoring the changes in land use can assist in future planning procedures to address the needs of future generations. Phosphorus export, which is the main cause of lake eutrophication, depends on the type of land cover occurring in the lakeshed. Figure 17 depicts the land cover in Lower Hay Lake s lakeshed. The University of Minnesota has online records of land cover statistics from years 199 and 2 ( Although this data is 12 years old, it is the only data set available for comparing land use changes over a decade s time. Table 1 describes Lower Hay Lake s lakeshed land cover statistics and percent change from 199 to 2. Due to the many factors that influence demographics, one cannot determine with certainty the projected statistics over the next 1, 2, 3+ years, but one can see the transition within the lakeshed from agriculture, grass/shrub/wetland, and water acreages to forest and urban acreages. The largest change in percentage is the decrease in grass/shrub/wetland cover (37%); however, in acreage, forest cover has increased the most (268 acres). In addition, the impervious intensity has increased, which has implications for storm water runoff into the lake. The increase in impervious intensity is consistent with the increase in urban acreage. RMB Environmental Laboratories, Inc. 14 of Lower Hay Lake

15 Table 1. Lower Hay Lake s lakeshed land cover statistics and % change from 199 to 2 ( % Change Land Cover Acres Percent Acres Percent 199 to 2 Agriculture % Decrease Grass/Shrub/Wetland % Decrease Forest % Increase Water % Decrease Urban % Increase Impervious Intensity % % Decrease % Increase % Increase % Increase % Decrease % Decrease No Change Total Area Total Impervious Area (Percent Impervious Area Excludes Water Area) No Change Demographics Lower Hay Lake is classified as a recreational development lake. Recreational development lakes usually have between 6 and 225 acres of water per mile of shoreline, between 3 and 25 dwellings per mile of shoreline, and are more than 15 feet deep. The Minnesota Department of Administration Geographic and Demographic Analysis Division extrapolated future population in 5- year increments out to 235. Compared to Crow Wing County as a whole, Jenkins Township has a higher extrapolated growth projection. However, Ideal Township has a similar extrapolated growth projection with Crow Wing County (Figure 18). Figure 18. Population growth projection for Jenkins and Ideal Township and Crow Wing County. (source: 32) RMB Environmental Laboratories, Inc. 15 of Lower Hay Lake

16 Lower Hay Lake Lakeshed Water Quality Protection Strategy Each lakeshed has a different makeup of public and private lands. Looking in more detail at the makeup of these lands can give insight on where to focus protection efforts. The protected lands (easements, wetlands, public land) are the future water quality infrastructure for the lake. Developed land and agriculture have the highest phosphorus runoff coefficients, so this land should be minimized for water quality protection. The majority of the land within Lower Hay Lake s lakeshed is made up of private forested uplands (Table 11). This land can be the focus of development and protection efforts in the lakeshed. Table 11. Land ownership, land use/land cover, estimated phosphorus loading, and ideas for protection and restoration in Lower Hay Lake s lakeshed (Sources: Crow Wing County parcel data, National Wetlands Inventory, and the 26 National Land Cover Dataset). Private (57.5%) 25.7% Public (16.8%) Developed Agriculture Forested Uplands Other Wetlands Open Water County State Federal Land Use (%) 1.6% 4.8% 24.4% 23.6% 3.1% 26% 8.2% 8.6% % Runoff Coefficient Lbs of phosphorus/acre/ year Estimated Phosphorus Loading Acreage x runoff coefficient Description Focused on Shoreland Cropland Focus of development and protection efforts Open, pasture, grassland, shrubland Protected Potential Phase 3 Discussion Items Shoreline restoration Restore wetlands; CRP Forest stewardship planning, 3 rd party certification, SFIA, local woodland cooperatives Protected by Wetland Conservation Act County Tax Forfeit Lands State Forest National Forest DNR Fisheries approach for lake protection and restoration Credit: Peter Jacobson and Michael Duval, Minnesota DNR Fisheries In an effort to prioritize protection and restoration efforts of fishery lakes, the MN DNR has developed a ranking system by separating lakes into two categories, those needing protection and those needing restoration. Modeling by the DNR Fisheries Research Unit suggests that total phosphorus concentrations increase significantly over natural concentrations in lakes that have watershed with disturbance greater than 25%. Therefore, lakes with watersheds that have less than 25% disturbance need protection and lakes with more than 25% disturbance need restoration (Table 12). Watershed disturbance was defined as having urban, agricultural and mining land uses. Watershed protection is defined as publicly owned land or conservation easement. RMB Environmental Laboratories, Inc. 16 of Lower Hay Lake

17 Table 12. Suggested approaches for watershed protection and restoration of DNR-managed fish lakes in Minnesota. Watershed Watershed Management Disturbance Protected Type (%) (%) Comments > 75% Vigilance Sufficiently protected -- Water quality supports healthy and diverse native fish communities. Keep public lands protected. < 25% Excellent candidates for protection -- Water quality can be maintained in a range that supports healthy and diverse native < 75% Protection fish communities. Disturbed lands should be limited to less than 25%. Realistic chance for full restoration of water quality and improve 25-6% n/a Full Restoration quality of fish communities. Disturbed land percentage should be reduced and BMPs implemented. Restoration will be very expensive and probably will not achieve > 6% water quality conditions necessary to sustain healthy fish Partial Restoration n/a communities. Restoration opportunities must be critically evaluated to assure feasible positive outcomes. The next step was to prioritize lakes within each of these management categories. DNR Fisheries identified high value fishery lakes, such as cisco refuge lakes. Ciscos (Coregonus artedi) can be an early indicator of eutrophication in a lake because they require cold hypolimnetic temperatures and high dissolved oxygen levels. These watersheds with low disturbance and high value fishery lakes are excellent candidates for priority protection measures, especially those that are related to forestry and minimizing the effects of landscape disturbance. Forest stewardship planning, harvest coordination to reduce hydrology impacts and forest conservation easements are some potential tools that can protect these high value resources for the long term. Lower Hay Lake is classified with having 38.7% of the watershed protected and 7.9% of the watershed disturbed (Figure 19). Therefore, Lower Hay Lake should have a protection focus. Goals for the lake should be to limit any increase in disturbed land use. In addition, Lower Hay Lake was designated by DNR Fisheries as a high valued fishery lake because of its cisco population. Figure 2 displays the upstream lakesheds that contribute water to the lakeshed of interest. All of the land and water area in this figure has the potential to contribute water to Lower Hay Lake, whether through direct overland flow or through a creek or river. Three of the 4 upstream lakesheds have the same management focus (protection). Percent of the Watershed Protected % 75% 1% Lower Hay Lake (38.7%) Percent of the Watershed with Disturbed Land Cover % 25% 1% Lower Hay Lake (7.9%) Figure 19. Lower Hay Lake lakeshed s percentage of watershed protected and disturbed. Figure 2. Upstream lakesheds that contribute water to the Lower Hay lakeshed. Color-coded based on management focus (Table 12). RMB Environmental Laboratories, Inc. 17 of Lower Hay Lake

18 Lower Hay, Status of the Fishery (as of 6/7/25) Lower Hay is a 685 acre lake that is part of the 14, acre Whitefish chain of lakes. Development is heavy with 121 homes/cabins on four miles of shoreline in The littoral area (area 15 feet deep or less) is 215 acres, or 31% of the surface area. Maximum depth is 1 feet and water clarity is good, with a secchi disc reading of 13 feet in mid-june, 25. In 25, Lake Whitefish, black crappie, bluegill, bowfin, largemouth bass and rock bass were sampled in high numbers. Walleye, yellow bullhead and yellow perch were sampled in low numbers. Northern pike, black bullhead, brown bullhead, tullibee, white sucker, pumpkinseed and shorthead redhorse were taken in average numbers compared to similar type lakes. Growth rates for all species were generally good. The walleye catch was 1.8/GN. Size averaged 17.4 inches and 2.3 pounds. The northern pike catch was 8.5/GN. Their size averaged 22.1 inches and 2.5 pounds. Bluegills were present in high numbers but 49% were at least 7 inches long. The black crappie catch was also high and 55% were at least 8 inches long. See the link below for specific information on gillnet surveys, stocking information, and fish consumption guidelines. Key Findings / Recommendations Monitoring Recommendations Transparency monitoring at site 24 should be continued annually. It is important to continue transparency monitoring weekly or at least bimonthly every year to enable year-to-year comparisons and trend analyses. Site 24 should be the primary site for Lower Hay Lake because it is the deepest, and it s located in the middle of the lake. In the past, data has been collected at site 22 and 25, but these are not the best representative sites for the lake conditions. All future phosphorus and chlorophyll a data should be collected at site 24. Overall Conclusions Overall, Lower Hay Lake has good water quality, and is in fairly good shape for lakeshed protection. It is a mesotrophic lake (TSI=43) with no trend in transparency over the past decade. Seventeen percent (17%) of the lakeshed is in public ownership, and 38% of the lakeshed is protected, while only 8% of the lakeshed is disturbed (Figure 19). The upstream lakeshed to the north of the lakeshed of interest, which contains the City of Jenkins, is even more disturbed (Figure 2). Lower Hay Lake is interesting limnologically because it is fairly small, but very deep (1 feet maximum depth). Due to the depth and lower nutrient levels, the oxygen is not completely depleted in the hypolimnion (Figure 9). This condition is excellent habitat for Cisco fish (Tullibee), which are excellent forage for gamefish. Lower Hay Lake was designated by DNR Fisheries as a high valued fishery lake because of its cisco population. Ciscos can be water quality indicators for eutrophication. RMB Environmental Laboratories, Inc. 18 of Lower Hay Lake

19 Priority Impacts to the lake The priority impact to Lower Hay Lake is the surrounding development and any future development. The majority of the shoreline is developed in the first tier. There is also development along Hay Creek, the inlet to the lake. Both the Cities of Pequot Lakes and Jenkins are in the watershed of Lower Hay Lake. As land is converted from forested uplands and agriculture to developed land use, the potential to increase phosphorus loading increases dramatically. Best Management Practices Recommendations The management focus for Lower Hay Lake should be to protect the water quality and the lakeshed. Protection efforts should be focused on managing and/or decreasing the impact caused by additional development, and impervious surface area. Project ideas include protecting land with conservation easements, enforcing county shoreline ordinances, smart development, shoreline restoration, rain gardens, and septic system maintenance. Stormwater management and sediment reduction in the cities of Pequot Lakes and Jenkins will benefit the area s lakes. In addition, maintaining or installing a 25 foot buffer along the length of Hay Creek will benefit the water quality in both Lower and Upper Hay Lakes. County-wide Recommendation In order to better manage the impact of septic systems on lake water quality, it is recommended that the county implement a lake-wide septic inspection program. In a program such as this, the county would focus on one to three lakes a year, pull septic system records on those lakes, and require old systems to be inspected. This program can rotate through the county doing a few lakes each year. Organizational contacts and reference sites Friends of Lower Hay Lake Whitefish Area Property Owners Association DNR Fisheries Office Regional Minnesota Pollution Control Agency Office Crow Wing Soil and Water Conservation District Crow Wing County Environmental Services Department Minnesota Drive, Brainerd, MN brainerd.fisheries@state.mn.us 7678 College Road, Suite 15, Baxter, MN , Crow Wing County Land Services Building 322 Laurel St. Suite 13, Brainerd, MN Crow Wing County Land Services Building 322 Laurel St. Suite 14, Brainerd, MN Funding This project was funded in part by the Board of Water & Soil Resources and the Initiative Foundation, a regional foundation. RMB Environmental Laboratories, Inc. 19 of Lower Hay Lake