Water quality monitoring of five major tributaries in the Otsego Lake watershed, summer 2013

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1 Water quality monitoring of five major tributaries in the Otsego Lake watershed, summer 2013 Christopher Teter 1 INTRODUCTION Pollution that enters a water body from diffuse sources is commonly called non-point source pollution. Overland runoff flows through soils, picking up pollutants and carrying them downward into water bodies. At lower elevations, pollutants may become concentrated in streams, rivers, ponds and lakes. Possible contaminants include excess fertilizers (phosphorus and nitrogen), herbicides, insecticides, sediment, salts, and bacteria (USEPA 2012). Because of heavy agricultural use in the Otsego Lake watershed, monitoring efforts focus on the nutrients phosphorus and nitrogen. Otsego Lake was previously classified as mesotrophic, with oligotrophic characteristics (Iannuzzi 1991). Through the 1990s, Otsego Lake had been exhibiting increasing characteristics of eutrophy (Albright 2001), namely increasing rates of deep water oxygen depletion during summer stratification. Nutrients added to the lake promote algal growth which, upon death, will decompose, consuming dissolved oxygen. The above situation has been compounded by the introduction of two exotic species. The introduction of the invasive fish species, alewife (Alosa pseudoharengus), by 1986 (Foster 1989) created eutrophication-like conditions in Otsego Lake because they effectively removed larger bodied crustacean zooplankton, which previously had been efficient algal grazers (Harman et. al. 1997). The additional introduction of zebra mussels (Dreissena polymorpha) in about 2008 increased lake clarity by decreasing phytoplankton populations through high rates of filtration (Waterfield 2009). Monitoring of the nutrients in the lake itself has not been wholly effective in determining the success of watershed nutrient control efforts because of the addition of these exotic fauna. Therefore, the direct monitoring of the available nutrients within Otsego Lakes tributaries is an important component of assessing effectiveness of agricultural best management practices (BMPs). This study is an annual continuation of work initiated in a 1996 study conducted by the SUNY College at Oneonta s Biological Field Station to evaluate the effectiveness BMPs that are currently in place within the Otsego Lake watershed (Hewett 1996). BMPs are conservation techniques recommended by the United States Department of Agricultures (USDA). In 1998, the municipalities surrounding the lake agreed upon a management plan, with priority given to reducing phosphorus inputs (Anon. 1998). Because 44 percent of the Otsego Lake watershed is being used for agricultural purposes (Harman et al. 1997), loading by this source was targeted for management. To date, 23 farms within close proximity to stream in the watershed have employed BMPs. The funding for these BMPs was provided for in part by the USDA 1 Rufus J. Thayer Otsego Lake Research Assistant, summer Current affiliation: SUNY Oneonta. Funded by the Otsego County Conservation Association.

2 Environmental Quality Incentive Program (Otsego County Water Quality Coordination Committee 1998). Techniques such as conservation tillage, crop nutrient management, pest management, manure storage management and conservation buffers are used to prevent soil erosion of, and reduce sediment and nutrient loading to streams. METHODS This year s data were collected in accordance with the methods of previous years (i.e., Mehigan 2013). The five tributaries monitored and the numbers of sample sites on each are: White Creek (3), Cripple Creek (5), Hayden Creek (8), Shadow Brook (5), and Mount Wellington (2). A list of sample sites is displayed in Table 1, along with their GPS coordinates and physical descriptions. The locations of the sample sites and their relation to current BMPs in use in the watershed are shown in Figure 1. These sites were chosen because of their accessibility and proximity to farms using BMPs. Each site was visited on the Tuesday of every week from 30 May to 6 August Physical parameters were recorded at each sample site using a YSI (6820 V2) multi-parameter water quality sonde. Before each use, the sonde was calibrated using the manufacturer s specifications. Water quality parameters measured included temperature ( C), ph, specific conductivity (µs/cm), oxidation reduction potential (mv), percent dissolved oxygen, oxygen concentration (mg/l), and turbidity (NTU). Chemical analyses were conducted using water samples collected at each point in 125ml acid washed plastic bottles. Samples were chilled until brought to the laboratory, where they were preserved to ph<1. Analysis of the samples included nitrite+nitrate, total nitrogen and total phosphorus concentrations. The analysis was conducted using Lachat QuikChem FIA+ Water Analyzer. Table 1. GPS coordinates and physical descriptions of sample locations (modified from Putnam 2010). White Creek 1 (WC1): N 42º W 74º South side of Allen Lake on County Route 26 over a steep bank. White Creek 2 (WC2): N 42º W 74º Plunge-pool side of stream on County Route 27 (Allen Lake Road) where there is a large dip in the road. White Creek 3 (WC3): N 42º W 74º West side of large stone culvert under Route 80, just past the turn to Country Route 27. Cripple Creek 1 (CC1): N 42º W 74º Weaver Lake accessed from the north side of Route 20 just past outflow of beaver dam.

3 Table 1 (cont.). GPS coordinates and physical descriptions of sample locations (modified from Putnam 2010). Cripple Creek 2 (CC2): N 42º W 74º Young Lake accessed from the west side of Hoke Road. The water at this site is shallow; some distance from shore is required for sampling. Cripple Creek 3 (CC3): N 42º W 74º North side of culvert on Bartlett Road. Cripple Creek 4 (CC4): N 42º W 74º Large culvert on west side of Route 80. The stream widens and slows at this point; this is the inlet to Clarke Pond. Cripple Creek 5 (CC5): N 42º W 74º Dam just south of Clarke Pond accessed from the Otsego Golf Club road. Samples were collected on the downstream side of the bridge. Hayden Creek 1 (HC1): N 42º W 74º Summit Lake accessed from the east side of Route 80, north of the Route 20 and Route 80 intersection. Small pull off but researcher must wade in the water to place the probe. Hayden Creek 2 (HC2): N 42º W 74º Downstream side of culvert on Dominion Road. Hayden Creek 3 (HC3): N 42º W 74º Culvert on the east side of Route 80 north of the intersection of Route 20 and Route 80. Hayden Creek 4(HC4): N 42º W 74º North side of large culvert at the intersection of Route 20 and Route 80. Hayden Creek 5 (HC5): N 42º W 74º Immediately below the Shipman Pond spillway on Route 80. Hayden Creek 6 (HC6): N 42º W 74º East side of the culvert on Route 80 in the village of Springfield Center. Hayden Creek 7 (HC7): N 42º W 74º Large culvert on the south side of County Route 53. Hayden Creek 8 (HC8): N 42º W 74º Otsego Golf Club, above the white bridge adjacent to the clubhouse. The water here is slow moving and murky. Shadow Brook 1 (SB1): N 42º W 74º Small culvert on the downstream side off of County Route 30 south of Swamp Road.

4 Table 1 (cont.). GPS coordinates and physical descriptions of sample locations (modified from Putnam 2010). Shadow Brook 2(SB2): N 42º W 74º Large culvert on the north side of Route 20, west of County Route 31. Shadow Brook 3 (SB3): N 42º W 74º Private driveway (Box 2075) off of County Route 31, south of the intersection of Route 20 and Country Route 31 leading to a small wooden bridge on a dairy farm. Shadow Brook 4 (SB4): N 42º W 74º One lane bridge on Rathbun Road. This site is located on an active dairy farm. The streambed consists of exposed limestone bedrock. Shadow Brook 5 (SB5): N 42º W 74º North side of large culvert on Mill Road behind Glimmerglass State Park. Mount Wellington 1 (MW1): N 42º W 74º Stone bridge on Public Landing Road adjacent to an active dairy farm. Mount Wellington 2 (MW2): N 42º W 74º Small stone bridge is accessible from a private road off Public Landing Road; at the end of the private road near a white house there is a mowed path which leads to the bridge. Water here is stagnant and murky. Sampled on the side opposite the lake before the confluence of Mount Wellington stream and the brook beside the golf course.

5 Figure 1. Map showing sampling locations of five tributaries in the northern watershed of Otsego Lake, as well as locations of BMPs (asterisks). Temperature RESULTS AND DISCUSSION Aquatic species, especially fishes, are sensitive to temperature changes. Highs and lows in temperature in a given water body can result in mortality or displacement of aquatic organisms (Mason 2002). In order to prevent these fluctuations, watershed managers may promote the growth of conservation buffers. These buffers allow vegetation to grow unmolested along stream and river banks, which allows streams to run cooler. Traditionally, the removal of woody plant species and tall herbaceous species along stream banks has allowed more sunlight to be absorbed by streambeds. Over the summer of 2013 the lowest value of C was located at site CC3, and the highest value of 31.9 C was located at HC2. The mean values ranged from C to

6 22.38 C. Last year s mean values ranged from C at MW1 to C at HC1 (Mehigan 2013). Figure 2 displays the mean temperatures recorded for the summer of Temperature (C) Mean Temperature Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 2. Mean Temperatures of sampling sites along the stream gradients of five major tributaries in summer Distance from the lake increases moving from left to right on the graph. ph Most organisms are sensitive to ph, which is an expression of the concentrations of positive hydrogen ions on a negative logarithmic scale from Aquatic organisms usually can only survive in the midranges of this scale (EPA 2012). The ph of water is heavily influenced by atmospheric, geological and biological processes. The ph of water also affects the availability of dissolved oxygen, nutrients, and toxic heavy metals. The lowest recorded value was 7.42 at site CC1, and the highest was 8.66 at HC1. The minimum and maximum mean ph values for sites in the summer of 2013 are 7.78 at CC2 and 8.33 at CC1 respectively. Last year s mean ph ranged from 7.82 at CC1 to 8.28 at HC4 in 2012 (Mehigan 2013).The northern reaches of the Otsego Lake watershed are fed by carbonate rich groundwater seepage (Fetterman & Burgin 1997), making samples more basic than those of other streams. Figure 3 displays the mean ph recorded for sites during the summer of 2013.

7 ph Mean ph Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 3. Mean ph of sampling sites along the stream gradients of five major tributaries in summer Distance from the lake increases moving from left to right on the graph. Conductivity Conductivity is a measure of a solution s ability to conduct electricity, which increases with increasing ion content (Wetzel 2001). This measurement can be used to identify possible polluted runoff. The lowest value recorded was ms/cm at site CC1, and the highest was ms/cm at site CC3. The minimum and maximum mean specific conductance values for sites in the summer of 2013 are ms/cm at WC1 and ms/cm at CC3 respectively. Mean conductivity readings in the summer of 2011 ranged from ms/cm at WC1 to ms/cm at MW2 (Zaengle 2012). Figure 4 displays the mean specific conductivity of sampling sites in the summer of Dissolved Oxygen Measurements of dissolved oxygen (DO) content show whether waters are favorable or unfavorable for fish and other organisms. Fish typically require more than 6mg/l (Murphy &Willis 1996). The amount of oxygen present in the tributaries of Otsego Lake can be affected by nutrient loading and a lack of shade for streams, two aspects that the USDA BMP s attempt to improve. Cooler waters can hold more DO (Wetzel 2001). The lowest value recorded was 3.64 mg/l at site CC1, and the highest was mg/l at site HC1. The minimum and maximum mean values for sites in the summer of 2013 were 6.47 mg/l at CC1 and mg/l at HC1 respectively. Mean site DO concentrations in 2012 ranged from 5.04 mg/l at CC1 to mg/l at SB4 (Mehigan 2013). Figure 5 shows the mean DO values for all sites sampled in 2013.

8 Mean Conductivity 0.6 Conductivity (ms/cm) Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 4. Mean conductivity of sampling sites along the stream gradients of five major tributaries in summer Distance from the lake increases moving from left to right on the graph. Disolved Oxygen (mg/l) Mean Dissolved Oxygen Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 5. Mean dissolved oxygen of sampling sites along the stream gradients of five major tributaries in summer Distance from the lake increases moving from left to right on the graph.

9 Turbidity Turbidity is a lack of clarity of water, usually due to the absorption and scattering of light by suspended inorganic particles (Wetzel 2001). These particles can contribute to siltation of substrates, disrupting lake and stream benthic communities. High concentration of suspended particles can affect fish species ability to absorb dissolved oxygen, find food, and reproduce (Jorgensen 2013). In the study of the Otsego Lake watershed, this has only been the second year of turbidity data collection. This data collection was facilitated by a turbidity sensor which has been added to the BFS YSI probe to collect in situ turbidity data. The minimum and maximum mean values for sites in the summer of 2013 were 1.47 NTU s at WC1 and 49.1 NTU s at SB5 respectively. The lowest values recorded were typically bellow detection levels for the probe used. The highest turbidity value recorded was NTU s at site SB5. In 2012, turbidity ranged from 3.68 NTU at CC3 to NTU at MW2 (Mehigan 2013). Figure 6 shows the mean turbidity of all sites sampled in Turbidity (NTU) Figure 6. Mean turbidity of sampling sites along the stream gradients of five major tributaries in summer Distance from the lake increases moving from left to right on the graph. Nitrogen Mean Turbidity Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Nitrogen is an essential nutrient for the growth of plants. Unnaturally high levels of nitrogen can be found in water bodies that receive runoff from agricultural lands. The addition of excess nitrogen to a system can increase its productivity (Wetzel 2001). Algae and plant growth will increase due to the increased availability of nitrogen as a fertilizer. Upon reaching the end of their growing season, decomposing plants and algae will contribute to the eutrophication of the lowest regions of the water column. The minimum and maximum mean values for the total nitrogen content of sites sampled in 2013 were mg/l at WC2 and 2.33 mg/l at SB2 respectively. The lowest value of 0.21 mg/l was recorded at WC1, and the highest value of 3.64 mg/l was recorded at SB2. In 2012, mean total nitrogen values ranged from 0.37 mg/l at WC1 to

10 2.3 mg/l at HC8 (Mehigan 2013). Figure 7 shows the mean total nitrogen of all sites sampled in Figure 8 shows the mean nitrite and nitrate concentrations for all sites sampled in Figure 9 shows the mean nitrite and nitrate concentrations at stream outlets since 1998, including data from Table 1 shows a comparison of mean nitrate concentrations since 1998, including data from Mean Total Nitrogen Total Nitrogen (mg/l) Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 7. Mean total nitrogen of sampling sites along the stream gradient of five major tributaries in summer Distance from the lake increases moving from left to right on the graph. Nitrate + Nitrite Concentrations (mg/l) Mean Nitrite + Nitrate Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 8. Mean nitrite + nitrate of sampling sites along the stream gradient of five major tributaries in summer Distance from the lake increases moving from left to right on the graph.

11 3 Mean Nitrite + Nitrate at Stream Outlet Nitrate (mg/l) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Stream Outlets Wellington Figure 9. Mean nitrate+nitrite at stream outlets of 5 tributaries in the northern watershed of Otsego Lake 1991,

12 Comparison of Mean Nitrate Concentrations (mg/l) WC WC WC CC CC CC CC CC HC HC HC HC HC HC HC HC SB SB SB SB SB MW MW * - - stream flow was too low for sample collection; no nutrient data exists for Site SB1 in 2012 Table 1. Comparison of mean nitrate concentrations (mg/l) is also included, but only the values for stream outlets were taken, where available.

13 Phosphorus Phosphorus is a component of many agricultural fertilizers. Phosphorus is an important component of all life, and is an essential mineral for the growth of flora and fauna. In Otsego Lake the addition of excess phosphorus can create increases in productivity, due to it being the limiting nutrient (Harman et al. 1997). In 2013 the minimum and maximum mean values for sites sampled in 2013 were 18.5 µg/l and µg/l. The lowest value of 5 µg/l was recorded at HC2 and the highest 1090 µg/l was recorded at MW2. In 2012, mean total phosphorus values ranged from 20 µg/l at HC4 to 71µg/L at MW2 (Mehigan 2013). Figure 10 shows the mean total phosphorus content of samples taken at each site in Figure 11 shows mean total phosphorus at stream outlets from 1996 to Table 2 is a comparison of phosphorus concentrations since Mean Total Phosphorus Total Phosphorus (ug/l) Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 10. Mean total phosphorus of sampling sites along the stream gradients of five major tributaries in summer Distance from the lake increases moving from left to right on the graph. Note High phosphorus readings at site MW2 required Y axis scale to be increased from 90 µg/l to 300 µg/l.

14 300 Mean Total Phosphorus at Stream Outlets Total Phosphorus (µg/l) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Stream Outlets Wellington Figure 11. Mean total phosphorus concentration (µg/l) at the most downstream sites (outlets) of 5 tributaries in the northern watershed of Otsego Lake

15 Comparison of phosphorus concentrations (µg/l), Site WC WC WC CC CC CC CC CC HC HC HC HC HC HC HC HC SB SB SB SB SB MW MW * - - stream flow was too low for sample collection; no nutrient data exists for Site SB1 in 2012 Table 2. Comparison of total phosphorus concentrations (ug/l) CONCLUSION From the middle of June, 2013, to July there were several weeks of record setting rainfall for Otsego and Herkimer Counties. This influenced this year s data by increasing the variability of the data set. Phosphorus and nitrogen values were higher than they have been for several tributaries compared to recent years. A cause of this could be found in the washing out of several dirt roads that cross Mount Wellington Creek, or unknown human disturbance. Physical parameters were not significantly different this year than those of the last. Temperature averages did seem to drop in the Hayden Creek and Shadow brook compared to last year. The ph values for all sites seemed to be less basic than previously reported. Dissolved oxygen seems to be slightly higher overall at most sites. Turbidity values are considerably higher than they have been in past years as well. Overall, these differences are typical of streams that receive increased rainfall. Increased strength and speed of a stream can: lower temperatures, lower ph values, introduce more ions into a stream, create more turbulence for oxygen to

16 dissolve into the water, and suspend more sediment in the water for longer (Ward & Elliot 1995). All of which are observed in this years data. It may also be worth noting that rainfall events seemed to mirror the sampling regime of our researcher. Sampling was done every Tuesday morning for the length of the study. Unfortunately, rain events seemed to happen often on Monday evenings. This rhythmic deviation from normal weather patterns may have skewed trends in our data set. This is an example as to why continued monitoring of the Otsego Lake tributaries is beneficial and necessary. Continued data collection will define more accurate trends in the water quality of a tributary. By recording data for several decades, researchers can paint a better picture of the effects of BMP placement in their watershed. REFERENCES Albright, M.F Otsego Lake limnological monitoring, In 34th Ann. Rept. (2001). SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. Anonymous A plan for the management of the Otsego Lake watershed. Otsego County Water Quality Coordinating Committee. Otsego County. New York. Fetterman, A. R., Burgin, B Preliminary geochemical analysis of surface and groundwater in Cripple Creek, a tributary to Otsego Lake, Otsego Co., New York.. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. Foster, J.R Introduction of alewife (Alosa pseudoharengus) in Otsego Lake. In 22 nd Ann. Rept. (1988). SUNY Oneonta Biol. Fld. Sta., SUNY Oneonta. Harman, W.N., L.P. Sohacki, M.R Albright and D.L. Rosen The State of Otsego Lake, Occasional Paper #30. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. Hewett, B. L Water quality monitoring and the benthic community in the Otsego Lake watershed. In 29 th Annual Report (1997). SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. Iannuzzi, T.J A model plan for the Otsego Lake watershed. Phase II: The Chemical limnology and water quality of Otsego Lake. Occasional Paper #23. SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. Jorgensen, S., Tundisis, J. G., Matsumura-Tundisi, T Handbook of inland aquatic ecosystems management. Mason, Christopher Frank. Biology of freshwater pollution. Pearson Education, 2002.

17 Mehigan, K Water quality monitoring of five major tributaries in the Otsego Lake watershed, summer In 45 th Ann. Rept. (2012). SUNY Oneonta Biol. Fld. Sta., SUNY Oneonta. Murphy, B.R., Willis, D. W. Fisheries techniques American Fisheries Society. Bethesda, MD. United States Environmental Protection Agency What is Non-point Source Pollution? Web. United States Environmental Protection Agency CADDIS Volume 2: Sources, Stressors & Responses (ph). Web. Ward, A. D., Elliot, W. J. Environmental Hydrology CRC Press, Boca Raton, FL. Waterfield, H.A Update on zebra mussel (Dreissena polymorpha) invasion and establishment in Otsego Lake, In 41 st Ann. Rept. (2008). SUNY Oneonta Biol. Fld. Sta., SUNY Oneonta. Wetzel, R.G Limnology, Lake and River Ecosystems, 3 rd edition. Academic Press. San Diego, California. Zaengle, O Water quality monitoring of five major tributaries in the Otsego Lake watershed, summer In 44 th Ann. Rept. (2011). SUNY Oneonta Biol. Fld. Sta., SUNY Oneonta.