WATER QUALITY REPORT HEALTH OF CANANDAIGUA LAKE AND TRIBUTARY STREAMS by Dr. Bruce A. Gilman ([email protected]) Department of Environmental Conservation and Horticulture Finger Lakes Community College 4355 Lakeshore Drive Canandaigua, New York 14424 and Kevin Olvany ([email protected]) Watershed Program Manager 205 Saltonstall Street Canandaigua, New York 14424 Prepared for: Canandaigua Lake Watershed Council 205 Saltonstall Street Canandaigua, New York 14424 Table of Contents: Executive Summary . 3 Acknowledgments . List of Figures . List of Tables . Introduction to Water Quality. Chapter 1 – Canandaigua Lake Research Canandaigua Lake Sampling and Monitoring Parameters . Methods . Results and Discussion . Chapter 2 – Tributary Research Methods . Results and Discussion . Recommendations and Topics for Future Research . Literature Cited . 2 Executive Summary: 1. Over the last three years, the health of Canandaigua Lake remained good to excellent. Dissolved oxygen was available throughout the water column at all monitoring times and often was at or near 100% saturation, ideal conditions for the survival of aquatic life. Seasonal temperature profiles characterized the development of thermal stratification typical of deep lakes. The pH was always above 7.00 (due to high buffer capacity of lake water), helping to protect the lake from the damaging effects of acidic precipitation storm events. Conductivity, a measure of ions dissolved in the water, averaged between 350 and 400 μS/cm. Recent increases in conductivity may stem from watershed development activities. Total phosphorus, the critical nutrient governing lake productivity and the element most responsible for lake eutrophication, was often below 10 μg/L during the monthly sample periods. Algal productivity, estimated by the concentration of chlorophyll a, ranged from 0.62 to 9.48 μg/L with a mean of 2.41 μg/L. 2. The average Carlson trophic state index of lake health continues to suggest that Canandaigua Lake remains an oligotrophic water body, however, the index based solely on chlorophyll a levels points to a mesotrophic state. Winter total phosphorus measurements should be conducted to prove or disprove this apparent trend towards nutrient enrichment. 3. Eelpot Creek contains the highest long-term total phosphorus concentration of all sampling locations (0.269 mg/L) and slightly exceeds the median concentration levels for total phosphorus in the NURP study. While steep gradient is one possible explanation, but it seems likely that excess sediments may also enter the creek where it flows over the Valley Heads moraine. 4. Gage Gully had the highest average nitrogen concentration over the last nine years with 4.11 mg/L. Deep Run was second with 2.95 mg/L. Fall Brook was third with 2.37 mg/L. Sucker Brook was fourth with 1.55 mg/L. Vine Valley was fifth with 1.21 mg/L. The long-term data show consistency from year to year. The National Urban Runoff Program (NURP) studies list a median concentration of 0.53 mg/L, thus these five streams are substantially higher than the NURP threshold. 4. Fisher Gully had the highest long-term concentration of total suspended solids with 398.8 mg/L. A substantial portion of the total suspended solids found in the watershed result from anthropogenic activities. 5. Based on approximately 70 samples from 1989 to 2005, Sucker Brook had the highest long- term concentration of fecal coliform with 725 colonies per 100 ml . These results suggest that the water is impacted by human wastes. 6. The annual road salt monitoring revealed lower than normal chloride concentrations (mg/L) in most tributary streams, with critical levels being exceeded only in Sucker Brook and the stream entering the lake at Cook’s Point. Although sampling is a “once a year snapshot”, these data reflect the severity of the winter seasons and the subsequent amounts of de-icing agents applied to highway surfaces. 3 Acknowledgments: This research was supported by the 14 municipalities comprising the Canandaigua Lake Watershed Council (Town of Bristol, City of Canandaigua, Town of Canandaigua, Town of Gorham, Town of Hopewell, Town of Italy, Town of Middlesex, Town of Naples, Village of Naples, Village of Newark, Town of Palmyra, Town of Potter, Village of Rushville, Town of South Bristol). We thank them for their continuing financial support and cooperative work in safeguarding the water quality of the lake. We also thank our interns, Alison Nihart, Alison Muehe, Kim Babcock and Valerie George for helping with data summary, graph preparation and editorial comments. Finger Lakes Community College provided administrative assistance from the Office of Resource Development and document reproduction through Central Office Services. The Science and Technology Department generously donated laboratory facilities. Use of boats and sampling equipment were provided by the Department of Environmental Conservation and Horticulture. Practicum students at the college helped collect scientific information, gained experience with equipment, presented findings at local conferences, and learned the value of limnological research programs. 4 List of Figures: 1.1 Development of thermal stratification in Canandaigua Lake, Deep Run Station. 1.2 Development of thermal stratification in Canandaigua Lake, Seneca Point Station. 1.3 Dissolved oxygen profiles in Canandaigua Lake, Deep Run Station. 1.4 Dissolved oxygen profiles in Canandaigua Lake, Seneca Point Station. 1.5 Secchi disk readings in Canandaigua Lake. 1.6 Chlorophyll a concentrations among sample stations in Canandaigua Lake. 1.7 Recent water quality trends in lake clarity and algal abundance. 1.8 Long-term trends in mean annual total phosphorus in Canandaigua Lake. 2.1 Canandaigua Lake sub-watersheds and direct drainage basins. 2.2 Total phosphorus weighed concentrations 1997-2005. 2.3 TSS weighted average concentrations 1997-2005. 2.4 NO3-NO2 weighted average concentrations 1997-2005. 2.5 Fecal coliform levels, 1989-2005. 2.6 Road salt contamination in Canandaigua Lake tributaries. 2.7 Long-term watershed chloride trends based on mid-winter sampling, 1990-2006. List of Tables: 1.1 Secchi disk readings (m) in Canandaigua Lake. 1.2 Chlorophyll a concentrations (μg/L) in Canandaigua Lake. 1.3 Ratio between shoreline (n = 3) and mid-lake (n = 2) chlorophyll a concentrations. 1.4 Total phosphorus data exceeding 10 μg/L, April 2003 through November 2005. 1.5 Seasonal profiles for total phosphorus (μg/L) at the two mid-lake sampling stations. 1.6 Monthly variation in mean inorganic nitrogen (NO3 + NO2 mg N/L) for mid-lake and shoreline sampling stations. 1.7 Information pertaining to the Carlson Trophic State Index (TSI). 1.8 Carlson TSI values for Canandaigua Lake. 2.1 Precipitation measurements and runoff totals during each storm event, 2001-2005. 2.2 Stream rankings, 1997-2005. 2.3 Combined average concentrations for each of the streams from 1997-2005. 2.4 Concentrations of nitrate/nitrite in Grimes Creek Raceway. 2.5 Concentrations of phosphorus, TSS, and nitrate/nitrite in the West River. 2.6 Chloride concentration (mg/L) in Canandaigua Lake tributaries, 2003-2006. 5 Introduction to Water Quality: This three year report updates our knowledge on the water quality of Canandaigua Lake and its tributary streams. The comprehensive, holistic approach utilized here draws on our research efforts and the historic work of others in order to better understand the consequences of human activities on water quality. Our primary goal is to inform and educate the Council and general public about significant issues that can adversely affect the lake. Our activities include extensive sampling and monitoring as well as a recent emphasis on predictive modeling utilizing many resource data bases in a geographic information system (GIS). While certain aspects of lake ecology have been studied since the early 1900’s, until recently the scientific research efforts have been sporadic. For the last 13 years, a regular sampling and monitoring program has reported on lake quality. This program provides an annual assessment of lake health and long-term analyses that, overall, suggest the lake remains clean and relatively pollution-free. However, concerns about the impacts of changing watershed land uses (e.g., residential development, forestry, agriculture, storm-water management) on lake water quality have arisen. Therefore, monitoring of perennial tributary streams and direct drainage sub-basins became a focus of our research during the mid 1990’s. Watershed drainages have been sampled under baseflow conditions and during meteorological events (e.g., storm runoff and snow melt runoff episodes). Streams contributing significant pollutants to the lake have been studied through segment analysis, helping to identify pollutant sources so remedial actions could be put in place. Point and non-point sources of pollution are well known for most water bodies but the relative significance among sources is not as clearly understood. Consistent and comprehensive sampling and monitoring programs can help determine the importance of point and non-point sources of pollution. Lake research coupled with watershed-wide stream pollutant sampling and monitoring for indicators of environmental degradation are essential steps in determining water condition. Knowledge of water condition should assist local municipalities in policy decisions and in the selection of watershed best management practices (BMPs) designed to restore, enhance and protect water quality. 6 CHAPTER 1 – CANADAIGUA