LAKE KANASATKA Water Quality Monitoring: 2013 Summary and Recommendations NH LAKES LAY MONITORING PROGRAM
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LAKE KANASATKA Water Quality Monitoring: 2013 Summary and Recommendations NH LAKES LAY MONITORING PROGRAM By: Robert Craycraft & Jeffrey Schloss Center for Freshwater Biology University of New Hampshire To obtain additional information on the NH Lakes Lay Monitoring Program (NH LLMP) contact the Coordinator (Jeff Schloss) at 603-862-3848 or Assistant Coordinator (Bob Craycraft) at 603-862-3696. This page intentionally left blank PREFACE This report contains the findings of a water quality survey of Lake Kanasat- ka, Moultonborough, New Hampshire, conducted in the summer of 2013 by the University of New Hampshire Center for Freshwater Biology (CFB) in conjunc- tion with the Lake Kanasatka Watershed Association. The report is written with the concerned lake resident in mind and contains an executive summary that discusses the 2013 and historical water quality data. Graphic display of data is included, in addition to listings of data in appendices, to aid visual perspective. A simplified and stand alone, three page, “Lake Kanasatka sampling highlight” document was also produced for distribution among interested residents and officials. i ACKNOWLEDGMENTS 2013 was the thirty-first year the Lake Kanasatka Watershed Association participated in the New Hampshire Lakes Lay Monitoring Program (LLMP). The volunteer monitors involved in the water quality monitoring effort are highlighted in Table 1. The Center for Freshwater Biology (CFB) con- gratulates the volunteer monitors on the quality of their work, and the time and effort Table 1: Lake Kanasatka put forth. We invite other interested resi- Volunteer Monitors (2013) dents to join the Lake Kanasatka water qual- Monitor Name ity monitoring effort in 2014 and expand up- Kevin & Sandra Kelly on the current database. Funding for the wa- Carol & Rick Carlson ter quality monitoring program was provided Enid Burrows by the Lake Kanasatka Watershed Associa- Rich Goulet tion while the CFB provided at-cost labora- tory services. The New Hampshire Lakes Lay Monitoring Program is a not-for-profit citizen based research program coordi- nated by Robert Craycraft and directed by Jeff Schloss, Associate Director of the UNH CFB. Members of the CFB-LLMP summer field team included Amy Ar- senault, Casey Chalmers and Hannah Johnson, while Jesica Waller provided additional assistance in the fall analyzing, compiling and organizing the water quality data. The LLMP acknowledges University of New Hampshire Cooperative Ex- tension for major funding and furnishing office and storage space while the Col- lege of Life Sciences and Agriculture provided laboratory facilities and additional storage space. The LLMP would like to thank the Caswell Family Founda- tion for their continued generosity in providing long-term support for under- graduate assistantships. Participating groups in the LLMP include: Acton-Wakefield Watershed Alliance, Green Mountain Conservation Group, North River Lake Monitors, the associations of Baboosic Lake, Bow Lake Camp Owners, Chocorua Lake, Conway Lake Conservation, Crystal Lake, Goose Pond, Governors Island, Great East Lake, Lake Kanasatka Watershed, Tuftonboro Islanders, Lovell Lake, Mendums Pond, Merrymeeting Lake, Milton Three Ponds Lake Lay Monitoring, Mirror Lake (Tuftonboro), Moultonborough Bay, Lake Winnipesaukee Watershed, Na- ticook Lake, Newfound Lake Region, Nippo Lake, Silver Lake (Madison), Squam Lakes, Sunset Lake, Swains Lake, Lake Wentworth, Winnisquam Drive, and the towns of Alton, Amherst, Enfield, Gilford, Laconia, Madison, Merrimack, Milton, New Durham, Strafford and Wolfeboro. Major collaborators with the UNH CFB in 2013 included the NH Water Resources Research Center, New Hampshire Lakes Association, New Hampshire Department of Environmental Services, Lakes Regional Planning Commission, Dartmouth Hitchcock Medical Center, Sandy Point Discovery Center (NH Fish and Game and Great Bay National Estuary Research Reserve), EPA New Eng- ii land, the Volunteer Monitoring National Facilitation Project (USDA) and the Northeastern States and Caribbean Islands Regional Water Center (USDA Na- tional Institute of Food and Agriculture). iii LAKE KANASATKA 2013 Executive Summary Water quality data were collected by the Lake Kanasatka volunteer moni- tors between May 27 and October 19, 2013 while a more in depth water quality survey of the Lake Kanasatka deep sampling stations (Sites 1 Deep, 2 Animal and 3 West) was conducted by the Center for Freshwater Biology (CFB) on August 4, 2013 to augment the volunteer monitoring data. Generally speaking, the 2013 Lake Kanasatka water quality remained high at the deep, centrally lo- cated, sampling locations as reflected by the clear water, the low levels of micro- scopic plant “algal” growth and the low phosphorus, nutrient, concentrations (Table 2). The following section discusses the 2013 and historical Lake Kanasatka water quality data. Refer to Appendix E for a complete listing of the 2013 Lake Kanasatka water quality data and refer to Appendix F for a summary of how to interpret the box and whisker plots that are included in this report. Table 2: 2013 Lake Kanasatka Seasonal Average Water Quality Readings and Water Quality Classification Criteria used by the New Hampshire Lakes Lay Monitoring Pro- gram. Eu- Parameter Ultraoligo Oligo Meso trophic Lake Kanasatka Lake Kanasatka “Outstanding” “Excellent” “Fair” “Poor” Average (range) Classification Water Clarity (meters) > 7.0 4.0 – 7.0 2.5 - 4.0 < 2.5 6.0 meters (range: 4.5 – 9.3) Oligotrophic Chlorophyll a (ppb) < 2.0 2.0 - 3.0 3.0 - 7.0 > 7.0 2.3 ppb (range: 0.5 – 3.5) Oligotrophic Total Phosphorus (ppb) < 7.0 15.0 – 7.0 15.0 - 25.0 > 25.0 8.3 ppb (7.6 – 8.9) Oligotrophic Cyanobacteria The Massachusetts Department of Public (cell counts, mi- Health considers dangerous microcystin The New Hampshire Department of Environmental services crocystin concen- (MC) levels to be 14 micrograms per liter posts warnings at State beaches when cyanobacteria cell tration & Water (ug/l) lake water, and/or 70,000 cyanobacte- numbers exceed 70,000 cells per milliliter lake water. safety) ria cells per milliliter lake water. * Total phosphorus and chlorophyll a data were collected in the surface waters (epilimnion). 1) Water Clarity (measured as Secchi Disk transparency) – The 2013 Lake Kanasatka water clarity values were high and were visible deeper than 4 meters (13.2 feet) that is considered the boundary between an unproductive "pristine" and a more nutrient enriched "transitional" New Hampshire lake (Ta- ble 3 and Appendix A). A comparison among the three deep sampling locations indicates the water was clearest at Site 1 Deep and significantly less clear at Sites 2 Animal and 3 West, during the 2013 sampling season (Table 3). iv The Lake Kanasatka annual Table 3: 2013 Water Clarity data summary median Secchi Disk transparency for the Lake Kanasatka deep sampling displays a trend of increasing long- stations. term water clarity at Site 1 Deep Site Seasonal Average Water and a relatively stable trend at Site Transparency (meters) 2 Animal since 1983. However, nei- 1 Deep 6.9 meters (range: 5.8 – 9.3) ther trend is statistically signifi- 2 Animal 5.0 meters (range: 4.5 – 5.8) cant (Appendix C). Site 3 West, 3 West 5.3 meters (range: 4.8 – 5.6) where water transparency meas- urements have been collected since 1994, exhibits a trend of increasing water transparency. The trend for Site 3 West is not statistically significant (Appendix C). 2) Microscopic plant abundance “greenness” (measured as chloro- phyll a) – The 2013 Lake Kanasatka seasonal chlorophyll a measurements gen- erally remained below the concentration of 3 parts per billion (ppb) that is con- sidered the boundary between a nutrient poor and more nutrient enriched "greener" lake (Table 4 and Appendix A). An inter-site comparison among the three deep Lake Table 4: 2013 Chlorophyll a data sum- Kanasatka sampling locations mary for the Lake Kanasatka deep indicates the chlorophyll a sampling stations. concentrations were lowest at the Site Seasonal Average deepest sampling location, Site 1 Chlorophyll a (ppb) Deep, relative to measurements 1 Deep 1.7 ppb (range: 0.5 – 2.7) collected at Sites 2 Animal and 3 2 Animal 2.6 ppb (range: 1.9 – 3.3) West (Table 4). 3 West 2.5 ppb (range: 1.8 – 3.6) The Lake Kanasatka annual median chlorophyll a concentrations display a trend of decreasing long-term chlorophyll a concentrations at Site 1 Deep and increasing long-term chlorophyll a concentrations at Site 2 Animal. Neither trend is statistically significant over the span of 1983 through 2013 (Ap- pendix C). The long-term chlorophyll a data analyzed at Site 3 West, 1994 through 2013, indicate a stable trend-line although the trend is not statistically significant (Appendix C). 3) Background (dissolved) water color: often perceived as a “tea” color in more highly stained lakes – The 2013 Lake Kanasatka dissolved color Table 5. Dissolved Color Clas- concentration averaged 15.5 chloroplati- sification Criteria used by the nate units (cpu) and fell within the classi- New Hampshire Lakes Lay fication of a slightly colored lake (Table 5). Monitoring Program. Dissolved color, or true color as it is some- times called, is indicative of dissolved or- Range Classification ganic carbon levels in the water (a by- 0 - 10 Clear 10 - 20 Slightly colored product of microbial decomposition). 20 - 40 Light tea color 40 - 80 Tea colored v > 80 Highly tea colored Small increases in water color from the natural breakdown of plant materials in and around a lake are not considered to be detrimental to water quality. Howev- er, increased color can lower water transparency, and hence, change the public perception of water quality. 4) Total Phosphorus: the nutrient considered most responsible for elevated microscopic plant growth in our New Hampshire Lakes. - Total phosphorus concentrations, measured in the surface waters (epilimnion), were low when collected by the volunteer monitors during the 2013 sampling season. The Lake Kanasatka total phosphorus values ranged from 7.6 to 8.9 parts per billion (ppb) at the three deep sampling locations (Figure 9) and remained below the concentration of 10 ppb that is considered sufficient to cause an algal bloom (Appendix E).