Water quality monitoring of five major tributaries in the Otsego Lake watershed, summer 2010

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1 Water quality monitoring of five major tributaries in the Otsego Lake watershed, summer 2010 Shane M. Putnam 1 INTRODUCTION Located in Otsego County New York, Otsego Lake is a nine mile long glacially overdeepended valley serving as the headwaters of the Susquehanna River and is geologically similar to the finger lakes of western New York State (Harman et. al 1997). At about 364 meters above sea level, this lake is bounded by Hamilton Group Shale on the east and west sides, an alluvial dyke to the south on which the village of Cooperstown sits, and Onondaga limestone to the north that acts as a ph buffer (Harman et. al 1997). Biologically, Otsego is a mesotrophic lake with an intermediate level of productivity, greater than that of oligotrophic lakes, but less than eutrophic lakes. Beds of submerged aquatic plants and medium levels of nutrients are indicative of these types of lakes; however, the lake includes flora and fauna commonly associated with oligotrophic lakes (Iannuzzi 1991). By the 1990 s trophic indicators implied the lake was becoming more eutrophic; Secchi disk transparency readings were rapidly decreasing along with dissolved oxygen levels within the hypolimnion. As early as the 1970 s, Otsego Lake was found to be in a state where slight changes in phosphorus loading were expected to produce large changes in transparency (Harman et. al 1997). A eutrophic state is characterized by elevated nutrient concentrations that lead to larger algal blooms and plant growth, and the depletion of the hypolimnion oxygen supply during periods of stratification when the decomposition of organic matter depletes deep water oxygen (Cook 1993). A eutrophic state degrades water quality, aesthetic appeal and drinking water quality, and negatively effects biotic diversity. Otsego Lake is used for recreational purposes including boating, swimming, and fishing, as well as supplying the village of Cooperstown s with drinking water, which makes nutrient loading an important issue. The watershed north of Otsego Lake is drained by White Creek, Cripple Creek, Hayden Creek, Shadow Brook, and a stream that forms on Mount Wellington. In the summer of 2010, these five tributaries of Otsego Lake were monitored for water quality as a continuation of ongoing research. Stream nutrient monitoring began in 1991 on all nine tributaries to the lake when nonpoint source pollution was being increasingly recognized as a major contributor to the degradation of the lake (Albright 1996). In the northern watershed, the major source of pollution appeared to be related to agricultural practices, for which 44% of the land is used in the basin 1 Rufus J. Thayer Otsego Lake research intern, summer Funding provided by OCCA. Undergraduate at SUNY College at Oneonta.

2 (Harman et. al 1997). Overland flow that is sourced on farms typically contains elevated levels of nutrients, particularly phosphorous and nitrogen. Such agricultural nutrient loading was given top priority for action in the plan to manage the Otsego Lake watershed (Anonymous 2007). In anticipation of agricultural non-point source Best Management Practice (BMP) funding in the mid-1990 s SUNY College at Oneonta s Biological Field Station identified locations affected greatest by agricultural practices. The USDA s Natural Resource Conservation Service developed a series of programs designed to reduce nutrient loading and subsequent eutrophication as a result of agriculture runoff. Voluntary BMPs focus on various agricultural aspects such as livestock management, waste management and storage, pest control, riparian vegetation, and soil erosion. These plans were implemented as a result of the 1996 Farm Bill that was proposed by the USDA Environmental Quality Incentive Program (Capraro 2010). Since 2004, 150 BMPs totaling over $2,750,000 have been put into operation all across Otsego County New York (Capraro 2010). Twenty-three sampling sites are monitored by the BFS to evaluate the impacts of the BMPs; measurements at each include nutrient concentration, temperature, dissolved oxygen, ph, and specific conductivity. The introduction of several exotic species has resulted in water quality fluctuations that make it difficult to determine whether the best management practices are having a positive effect on the lake. In 1986 alewife (Alosa pseudoharengus) were illegally introduced into the lake, which mimics the effects of nutrient loading (Harman et. al 1997). Alewife feed on zooplankton, which allows phytoplankton to grow in greater abundance and result in depletion of dissolved oxygen during decomposition. In an attempt to control the alewife population, walleye (Sander vitreus) were re-introduced in In 2007 zebra mussels (Dreissena polymorpha) were found to be colonizing the lake. These invasive mussels selectively filter planktons and out-compete almost every other filter feeder (Anonymous 2005). In 2010 the lake had the highest Secchi reading on record with 14.6 meters, likely a result of the zebra mussel colonization. It is expected that the introduction of these two invasive species has had a major effect on observed water quality. METHODS The methods of data collection were carried out in accordance with the previous years of this study. Samples were collected weekly from 25 May until 11 August 2010 at the 23 defined sites, which are located on the five tributaries of the lake found in the northern watershed. These locations were established in 1995 (Heavey 1996) and expanded in 1996 (Hewett 1997) to better monitor the effectiveness of the BMPs. The sampling locations are numbered in white circles and the BMPs are shown as asterisks in Figure 1. The physical descriptions and GPS coordinates of sampling sites are included in Table 1.

3 Water samples were collected at each site in an acid washed 125ml sample bottle, kept in a cooler while in the field, and then brought back to the lab where they were preserved with sulfuric acid to ph <1.0. These samples were processed weekly using a Lachat QuikChem FIA+ Water Analyzer. All samples were tested for nitrate + nitrite nitrogen and total nitrogen using the cadmium reduction method (Pritzlaff 2003), with the additional step of peroxodisfulfate digestion for the total nitrogen, and total phosphorus using ascorbic acid following persulfate digestion (Liao and Martin 2001). Ammonia was periodically tested for using the phenolate method (Liao 2001) but is not discussed in this report since it was below the detection level at each site. Additionally, a Eureka multi-parameter sensing probe was employed to monitor temperature, dissolved oxygen, ph and specific conductivity. Prior to every sampling event this probe was calibrated using the manufacturer s instructions. Figure 1. Map showing the numbered sampling locations and 5 tributaries in the northern watershed of Otsego Lake; BMPs are represented by black asterisks.

4 Table 1. GPS coordinates and physical descriptions of sample locations (modified from Waterfield 2009). Sites are represented in Figure 1. White Creek 1: N 42º W 74º South side of Allen Lake on County Route 26 over a steep bank. White Creek 2: 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: N 42º W 74º West side of large stone culvert under Route 80, just past the turn to Country Route 27. Cripple Creek 1: N 42º W 74º Weaver Lake accessed from the north side of Route 20 just past outflow of beaver dam. Cripple Creek 2: N 42º W 74º Young Lake accessed from the west side of Hoke Road. The water at this side is shallow; some distance from shore is required for sampling. Cripple Creek 3: N 42º W 74º North side of culvert on Bartlett Road. Cripple Creek 4: 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: 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: 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: N 42º W 74º Downstream side of culvert on Dominion Road. Hayden Creek 3: 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: N 42º W 74º North side of large culvert at the intersection of Route 20 and Route 80. Hayden Creek 5: N 42º W 74º Immediately below the Shipman Pond spillway on Route 80.

5 Table 1 (cont.). GPS coordinates and physical descriptions of samplings (modified from Denby 2008). Sites are represented in Figure 1. Hayden Creek 6: N 42º W 74º East side of the culvert on Route 80 in the village of Springfield Center. Hayden Creek 7: N 42º W 74º Large culvert on the south side of County Route 53. Hayden Creek 8: 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: N 42º W 74º Small culvert on the downstream side off of County Route 30 south of Swamp Road. Shadow Brook 2: N 42º W 74º Large culvert on the north side of Route 20, west of County Route 31. Shadow Brook 3: 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: N 42º W 74º One lane bridge on Rathburn Road. This site is located on an active dairy farm. The streambed consists of exposed limestone bedrock. Shadow Brook 5: N 42º W 74º North side of large culvert on Mill Road behind Glimmerglass State Park. Mount Wellington 1: N 42º W 74º Stone bridge on Public Landing Road adjacent to an active dairy farm. Mount Wellington 2: 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 lake side.

6 RESULTS & DISCUSSION Temperature The absorption of solar energy by a stream or lake is influenced by its physical and chemical properties. For small streams, shady vegetation along the banks and reduced overland flow limit warming. Temperature is a fundamental variable of a freshwater ecosystem and a change can be used as an indicator of water quality. Some organisms, including brown, brook, and rainbow trout, can only survive in cold waters where the dissolved oxygen is higher than in warm waters. A focus of BMPs has been riparian vegetation buffer zones that reduce the volume of overland flow containing excess nutrients entering streams. These vegetated zones have an added benefit of providing shade to streams. In the summer of 2010 mean temperatures ranged from 17.39ºC at Cripple Creek 3 to 23.56ºC at Hayden Creek 1 (Figure 2). These values are similar to the summer of 2009 when mean temperatures ranged from 15.9ºC at Cripple Creek 3 to 21.2ºC at Hayden Creek 1 (Waterfield 2009). Temperature (C) Mount Wellington Mean Temperature of Sampling Site White Creek Hayden Creek Cripple Creek Shadow Brook Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 2. Mean temperatures (ºC) for the summer of 2010 along the 5 tributaries of Otsego Lake in the northern watershed. Points on the left side of the graph represent the stream mouths while points on the right represent the headwaters. Dissolved Oxygen Dissolved oxygen (DO) is essential to the metabolism of all aerobic aquatic organisms and is a fundamental ingredient in the decomposition of organic material that fuels nutrient cycles (Wetzel 2001). Low concentrations of DO can indicate a eutrophic state, which is inversely related to the amount of organic matter in a formerly mesotrophic lake. Most warm water organisms cannot tolerate oxygen concentrations below 3mg/L (Novotny 1994). In the summer of 2010, mean DO concentrations ranged from 3.60mg/L at Whites Creek 1 to 9.42 mg/l at Shadow Brook 2. These concentrations are lower than the previous three summers when

7 values ranged from 4.81 mg/l at Hayden Creek 1 to 10.2 mg/l at Shadow Brook 4 (Waterfield 2009). However, mean temperatures were higher than in previous years, which are perhaps reducing the oxygen concentrations. Sensitive species may be negatively impacted at concentrations below 6mg/L; two sites (White Creek 1 & Cripple Creek 1) had concentrations below this value. The mean DO for each site is shown in Figure Mean Dissolved Oxygen of Sampling Site 10.0 Disolved Oxygen (mg/l) Mount Wellington White Creek Hayden Creek Shadow Brook Cripple Creek Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 3. Mean dissolved oxygen (mg/l) for the summer of 2010 along the 5 tributaries of Otsego Lake in the northern watershed. Points on the left side of the graph represent the stream mouths while points on the right represent the headwaters. ph and Conductivity ph is a measure of the concentration of hydrogen ions. It is important because it determines the solubility and biological availability of chemical nutrients and heavy metals. An extremely low ph can leach excessive heavy metals into the water and poison aquatic organisms. ph can also be an indicator of the amount of organic decomposition which may tax the dissolved oxygen supply. Mean ph values were within an anticipated range given the geology of the watershed and historical data, with mean values ranging from 7.3 to 8.3 across the northern watershed. Last year s mean ph values ranged from 7.4 to 8.4 (Waterfield 2009). The conductivity of water is the measure of its resistivity to electrical flow and is closely related to the concentrations of the major ions (Wetzel 2001). It can be used as a measure of pollution levels, with a sudden spike in conductivities representing a potential contamination plume. Also, the source of stream flow can control the conductivity; rain water has lower conductivities then groundwater baseflow, which has had time to leach ions from the strata. In the summer of 2010, the mean conductivity value ranged from 0.25µs/cm to 0.54µs/cm which is analogues to previous years of this study.

8 Phosphorus Phosphorus is a nutrient that is required for the growth of aquatic vegetation, and in Otsego Lake it is believed to limit productivity (Harman et.al 1997). This nutrient has been monitored with the greatest intensity since 1968 due to its importance (Harman et.al 1997). Excess phosphorus comes from agricultural runoff (Harman et.al 1997), septic seepage (Meehan 2004), and residential use (Albright 2005), which can accelerate production and increase the amount of organic material in the lake. The highest phosphorous concentration of 306µg/L was found at Cripple Creek 1 on 11 August 2010 after a tree was planted and fertilized near the site, while the lowest was found at Cripple Creek 2 the week of 29 June 2010 with 8.38µg/L. The mean lowest concentration was 16.8µg/L at Whites Creek 3 and the mean highest concentration was 67.9µg/L at Mount Wellington 2; these values represent concentrations and not loads (see Figure 4). Even though Mount Wellington 2 has the highest concentrations of phosphorous it has the lowest load as the discharge of this small drainage is the least of all the 5 tributaries. Since 1996 mean total phosphorus has been declining in most sites, though remains variable. A comparison of the mean phosphorus concentration at each tributary mouth from 1996 to 2010 is displayed in Figure 5. A comparison of the mean phosphorus concentrations for each sampling locations over the last 10 years is shown in Table 2. Total Phosphorus (ug/l Mount Wellington Mean Total Phosphorus of Sampling Site White Creek Hayden Creek Cripple Creek Shadow Brook Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 4. Mean total phosphorus (µg/l) for the summer of 2010 along the 5 tributaries of Otsego Lake in the northern watershed. Points on the left side of the graph represent the stream mouths while points on the right represent the headwaters.

9 250 Mean Phosphorus at Stream Outlets 200 Total Phosphorus (ug/l) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Stream Outlets Figure 5. A comparison of mean phosphorus (µg/l) concentrations at each stream mouth from Table 2. Comparison of mean phosphorus (µg/l) concentrations at each sampling location from Comparison of phosphorus concentrations (ug/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

10 Nitrogen The second most important nutrient to be considered in this study is nitrogen, which is also essential for algal production. In lakes where phosphorus levels are very high, growth may be limited by nitrogen as opposed to phosphorous. In these nitrogen limited systems, a sudden increase in loading can lead to eutrophic conditions. Nitrogen is added to lakes by way of precipitation, from fixation of atmospheric nitrogen, or surface and groundwater drainage (Wetzel 2001). Anthropogenic influences, namely agricultural practices and septic systems, enhance the amount of nitrogen entering Otsego Lake. Total nitrogen (TN) is an all-encompassing summation of nitrate + nitrite, ammonia, and organic forms of nitrogen. Ammonia testing was discontinued in 2010 on the northern watershed of Otsego Lake after concentrations were repeatedly below the minimum detection limit (<0.02 mg/l). Mean TN concentrations for each sampling site were not compiled for the summer of 2009; however, since the summer of 2006 mean low concentrations have increased. Cripple Creek 2 was the site with the lowest mean TN values in 2006 with 0.26mg/L (Snyder 2006), in 2007 with 0.34mg/L (Bueche 2007), and in 2008 with 0.47mg/L (Denby 2008); while Cripple Creek 1 had the lowest mean total nitrogen in the summer of 2010 with 0.51mg/L. Shadow Brook 2 had the highest concentration of TN in the summer of 2010 at 2.03mg/L. White Creek maintained the lowest average concentration over its drainage at 0.56mg/L and Hayden Creek had the highest average of 1.50mg/L. The mean total nitrogen concentration at each sampling location can be seen in Figure Mean Total Nitrogen at each Sampling Site 2.0 Total Nitrogen (mg/l) Mount Wellington White Creek Hayden Creek Cripple Creek Shadow Brook Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 6. Mean total nitrogen (mg/l) for the summer of 2010 along the 5 tributaries of Otsego Lake in the northern watershed. Points on the left side of the graph represent the stream mouths while points on the right represent the headwaters.

11 Nitrate is the dominate form of nitrogen in surface waters and is soluble, easily leeched, and highly mobile (Morton, 1976). It is also most biologically available to producers and is associated with oxidizing, aerobic environments (McClain et. al, 1998). Mean nitrate + nitrite concentrations were as low as 0.025mg/L at Cripple Creek 1, which is just above the detection limit of 0.02mg/L, and as high as 1.34mg/L at Shadow Brook 2. For 21 of the sample locations the nitrate concentrations were lower than they had been in The mean high concentration in the summer of 2010 was lower than the previous year s value of 1.9mg/L (Waterfield 2009) and higher than the summer of 2008 s value of 0.97mg/L (Denby 2008). On June 23, 2010, an impressively high value of 9.02mg/L was recorded at Mount Wellington 2 after a significant storm event. The mean nitrate + nitrite concentrations for the northern watershed are displayed in Figure 8. A comparison of the mean nitrate + nitrite concentration at each stream mouth (1991, ) is displayed in Figure 9. Table 3 displays a comparison of the mean nitrate + nitrite concentrations at each site from If nitrate + nitrite concentrations were observed below detection (0.02 mg/l) then they were considered to be 0 mg/l for graphing purposes. Nitrate + Nitrite Concentrations (mg/l) Mean Nitrate + Nitrite at each Sampling Site Mount Wellington Shadow Brook Hayden Creek White Creek Cripple Creek Distance from Otsego Lake (km) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Figure 7. Mean nitrate + nitrite (mg/l) for the summer of 2010 along the 5 tributaries of Otsego Lake in the northern watershed. Points on the left side of the graph represent the stream mouths while points on the right represent the headwaters.

12 3 2.5 Mean Nitrate at Stream Outlet Nitrate (mg/l) White Creek Cripple Creek Hayden Creek Shadow Brook Mount Wellington Stream Outlets Figure 8. A comparison of mean nitrate (mg/l) concentrations at each stream mouth from 1991, Table 3. Comparison of mean nitrate (mg/l) concentrations at each sampling location from 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

13 CONCLUSION The quality of Otsego Lake can be only as good as its source of water. The northern watershed composes 64% of the area of the total catchment and is by far the largest contributor of the hydrologic and nutrient budget (Harman et.al 1997). As a part of the plan to manage the lake, over $350,000 has been spent since 1998 to install and maintain 22 Best Management Practices. Water quality has shown some general improvements since 1998; however, the data collected in 2010 was not overly homogeneous in representing a positive result. Temperatures were higher than in the previous year, possibly causing a lower range of dissolved oxygen. The lowest mean total nitrogen was higher than in the past four years, but 21 of 23 of the sampling sites there has been an improvement in the mean nitrate since Total phosphorous has been declining since the beginning of the study with some variation. This study occasionally captures high precipitation anomalies in its data which tend to increase the average concentration and estimated load of nutrients in the tributaries. The summer of 2010 captured several rain events, which may explain an increase in the phosphorous concentration as compared to the previous year. A more thorough investigation of nutrient loads during rain events may prove valuable in evaluating the effectiveness of the BMPs. The improvements observed since 1998 could be a result of the BMPs, but more data must be collected to validate this hypothesis. REFERENCES Albright, M.R Changes in water quality in an urban stream following use of organically derived deicing products. Lake and Reservoir Management. 21(1): Anonymous Rapid response plan for the zebra mussel (dreissena polymorpha) in Massachusetts. Massachusetts Department of Conservation and Recreation. Boston, Massachusetts. Anonymous A Plan for the Management of the Otsego Lake Watershed. Otsego County Water Quality Coordinating Committee. Otsego County. New York Bueche, C. J Water Quality Monitoring of Five Major Tributaries in the Otsego Lake Watershed, summer In 40th Ann. Rept. (2007). SUNY Oneonta Bio. Fld. Sta., SUNY Oneonta. Capraro, T Personal Phone Communication. 20 August Cook, G. D., Welch, E. B., Peterson, S. A., Newroth, P. R Restoration and Management of Lakes and Reservoirs. Lewis Publishers. Bocca Raton p. Denby, J Water quality monitoring of five major tributaries in the Otsego lake watershed, summer In 41st Ann. Rept. (2008). SUNY Oneonta Biol. Fld. Sta., SUNY Oneonta.

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15 Wetzel, R. G Limnology, Lake and River Ecosystems, 3rd edition. Academic Press. San Diego, California.