Water Quality in Apple Canyon Lake Seth Sample, Michael J. Malon, Aren Helgerson, Adam Hoffman Abstract Anthropogenic land-use change over the past 200 years has led to severe water quality issues throughout the Mississippi River Basin. In 2012, Apple Canyon Lake (ACL) and the Jo Davies County Soil & Water Conservation District (SWCD) worked with members of the Environmental Science Department at the University of Dubuque (UD) to conduct a pilot study on water quality of inflow—and outflow—of the ACL. Studying concentrations of nitrates, concentrations of phosphates, and densities of fecal colliform bacteria colonies are three effective methods of understanding the causes and severity of poor water quality. Water quality tests were conducted on samplings from nine locations around ACL every month from late spring (May) through early fall (September). Important data was gathered from this pioneer study, although a presiding factor of drought created a complication in analysis. Introduction It has become increasingly clear that anthropogenic land-use change over the past 200 years has led to severe water quality issues throughout the Mississippi River Basin and the Gulf of Mexico (Hunsaker & Levine 1995; Turner & Rabalais 1991). While over-enrichment (eutrophication) in streams often leads to hypoxic and anoxic environments which choke out respiring aquatic organisms (Diaz & Rosenburg 1995), excessive runoff from various nonpoint sources negatively affect the quality of life for both aquatic and terrestrial animals—such as humans (Barnes et al. 2001). Two critical indices of eutrophication are nitrates and orthophosphates. Nitrates often appear in water bodies due to fertilizer runoff and livestock manure runoff. Studying colonial densities of fecal colliform bacteria (e.g. Escherichia coli, more commonly known as E. coli) is often a valuable indication of how nitrates enter the water (Mallin et al. 2000). Even small amounts of orthophosphates (PO3) are readily taken up by phytoplankton (like algae) and aquatic plants which often leads to excessive blooming (EPA 2012). These large blooms, at the end their life cycles, sink as detritus to the water body’s substrate where they are consumed by aerobic bacteria. These aerobic bacteria multiply in great numbers due to the temporary increased energy supply, and essentially starve the aquatic ecosystem of dissolved oxygen which faunal communities need for survival. Apple Canyon Lake (ACL) and the Jo Davies County Soil & Water Conservation District (SWCD) worked with members of the Environmental Science Department at the University of Dubuque (UD) to study the water quality of water flowing into—and out of—the Apple Canyon Lake, an impoundment of Hell’s Branch with six major tributaries. This pilot study at ACL was conducted from late spring (May) through early fall (September) of 2012. Three primary indicators were tested to gauge water quality: total phosphorus (ppm), nitrates (ppm), and fecal colliform bacteria (colonies/100 ml). Methods Water quality tests were conducted on samplings from nine locations around ACL. Sampling was conducted once a month (from May through September), in the middle of every month, and after rain events. However, due to the severe drought of 2012 when this project was administered, no significant rain events occurred outside the monthly testing regime. Sampling was completed by filling collection jars with surface water from each of the nine test sites, labeled 1 through 9 (see Map 1 below). Sampling began with Site 1, at Koester’s Pond, on the western side of ACL. Sampling then moved in a clockwise fashion around the lake, generally Map 1 following Apple Canyon Road. The final sampling site, Site 9, was located just downstream from the waterfall on South Apple Canyon Road. Three primary factors were used to determine aspects of ACL’s water quality during the year of 2012. We tested for the presence of phosphates, nitrates, and E. coli. Phosphorus was measured to determine reactive phosphorus, which consists of adding a phosphate complexing reagent to the unfiltered water samples and then measuring the absorbance at 880 nm (APHA, 1999). This will measure dissolved phosphates in the water and the loosely sorbed sediment bound phosphorus. Nitrite and nitrate were measured using Hach Aquacheck™ test strips. Fecal Coliform bacteria, including E. coli was determined by counting bacterial colonies following inoculation with Coliscan Easygel™ and a 48 hour incubation. Results The presiding factor of drought, and its effects on both nutrient and fecal colliform concentrations, creates a complication in analysis (Hirsch et al. 1982). Drought effect in regard to nutrient loading, fecal colliforms, and other ecological impacts is also an area of study that is considerably under-researched (Lake 2003). The results of this project may be beneficial to both the ACL community and to the scientific community, as it provides several months of data that can contribute to a growing body of evidence concerning drought effects on water quality. Total phosphorus (P) concentrations, yielded results for all sample sites—except two sites during the month of September. In the cumulative graph below (Graph 1), each of the nine sites are expressed chronologically. In Graphs 2 and 3 below, monthly trends in various sites are provided. Observable trends in correlation with the drought are as follows: Sites 2 and 3 were completely dry by September and, therefore, no water sampling could be taken. All values for Sites 2 and 3, for the month of September, were listed as 0. The drought’s effect on water systems became most noticeable by the month of July 2012. There tends to be a general upward trend in total phosphorus levels during the month of July, except for Site 7 (the golf course). However, as will be seen below, nitrate levels tend to dip during the month of July (except Site 8). Nitrate testing was partially conducted on site and partially in a lab at the University of Dubuque (UD). Graph 4 below gives a visual representation of the chronological cumulative nitrate (NO3) data. Once again, Sites 2 and 3 were given values of 0 for the month of September, due to drought effects. Fecal colliform bacteria (E. Coli) concentrations were also conducted at each site for every month, with the exception of Sites 2 and 3 in September. Graph 5 below shows the chronological cumulative E. Coli data. Graph 1 Cumulative Graph for Total P Concentrations (ppm) 0.600 Total P (ppm) 0.500 Site 1 Site 2 0.400 Site 3 Site 4 0.300 Site 5 0.200 Site 6 Site 7 0.100 Site 8 Site 9 0.000 May June July August September Time Graph 2 Graph 3 Correlative Graph for Sites 1, 3, & 8 Correlative Graph for Sites 5, 6, & 9 0.500 Site 1 0.400 Site 3 0.300 Site 8 0.200 0.100 0.000 Time Total P (ppm) Total P (ppm) 0.600 0.080 0.070 0.060 0.050 0.040 0.030 0.020 0.010 0.000 Site 5 Site 6 Site 9 Time Graph 4 Cumulative Graph for NO3 Concentrations (ppm) 2.500 Site 1 2.000 NO3 (ppm) Site 2 Site 3 1.500 Site 4 1.000 Site 5 Site 6 0.500 Site 7 Site 8 0.000 May June July August September Site 9 Time Graph 5 Cumulative Graph for E. Coli Concentrations (colonies/100 mL) 250.00 Site 1 E. coli (col/100 mL) 200.00 Site 2 Site 3 150.00 Site 4 100.00 Site 5 Site 6 50.00 Site 7 Site 8 0.00 May June July Time August September Site 9 While no overall E. Coli trends were discovered, a particular site during the month of July is noteworthy. At Site 8 there was a common spike in all three data sets (phosphorus, nitrates, and fecal colliforms) where there were, during other months, negligible amounts of each. Graph 6 below describes this trend. Graph 6 Site 8 E. coli (col/100 mL) 1.200 1.000 0.800 Phosphorus 0.600 Nitrates 0.400 E. Coli 0.200 Graph 6: For the purposes of creating a readable graph an arbitrary number (1) was given for E. Coli, to represent the colonial peak in July (a density of almost 200 colonies/100 ml). 0.000 Time Discussion The drought creates a difficulty in data interpretation, but certain trends did arise. In Graph 6 above, there was a significant spike in all 3 data collection factors in the month of July. July also signified the first noticeable effects of the drought in the ACL watershed. Site 8 is located just downstream from a culvert, which funnels the drainage from a small recreational park near the golf course. Along with the drought, anthropogenic factors should be considered as Koester’s Pond was dredged during the month of August. Note in Graph 4 above that Sites 1 (Koester’s Pond) and 2 (the stream that runs off from Koester toward ACL) have noticeable nitrate level spikes during the month of August. It should also be noted that there is a cattle pasture just upstream, to the northwest of Koester’s Pond. In future studies, data could be gathered using a number of other factors to determine both the health of the biotic community and the tributary effects on ACL. Taking data for Total Suspended Solids (TSS) along with flow rates would be beneficial to determine the approximate amount of sediment traveling into the ACL. Ammonia data were originally intended to be gathered for this pilot study, but unfortunately limited time and resources did not permit this. Finally, a thorough Rapid Assessment of Stream Conditions Along Length (RASCAL), in which the technician documents such factors as bank stabilization and canopy cover, could be beneficial in determining the health of aquatic wildlife communities which would also have benefits for the recreational aspects of ACL downstream. References APHA. 1995. Standard Methods for the Examination of Water and Wastewater. 19th Edition. American Public Health Association, Washington, DC. Barnes, K. B., et al. (2001). Impervious surfaces and the quality of natural and built environments. Baltimore: Department of Geography and Environmental Planning, Towson University. Diaz, R. J., & Rosenberg, R. (1995). Marine benthic hypoxia: a review of its ecological effects and the behavioural responses of benthic macrofauna. Oceanography and marine biology. An annual review, 33, 245-03. EPA. (2012). 5.6 Phosphorus. Water: Monitoring and Assessment. Environmental Protection Agency, 2012, March 6. 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