Effects of Development on the Big Darby Creek
Effects of Development on the Big Darby Creek Watershed: Stream Geochemistry Catherine Maxwell, School of Earth Sciences, The Ohio State University, Columbus, Ohio, 43210 -1398 W. Berry Lyons, Byrd Polar Research Center, The Ohio State University, Columbus, Ohio, 43210 1. Introduction 3. Long-Term Time Series Data 5. Discussion The Big Darby Creek is categorized as a national scenic river with an array of biological species. Since this is one of the last pristine rivers in Ohio, concern has grown in regards to human disturbances to the system. Its watershed has been mainly used for agricultural purposes since early pioneers settled the area. Recently, the outskirts of Columbus have been expanding westward into the watershed. Changes in the land use from rural to suburban should leave an impression on the chemistry of the stream water. Long-term stream chemistry analysis will show the effect of human activities on the Big Darby Creek. • Cl- concentrations in the Little Darby are in the 400 M range in the late 1960 s and early 1970 s, then in the 1980 s concentrations drastically increase to between 705 M and 1128 M, then remain close to those high values throughout the rest of the study. • Concentrations of anions in the Darby are similar to other Ohio Rivers that are influenced by agriculture such as the Scioto River. NO 3 - in the stream water is probably from agricultural sources. 2. Methods and Analysis • SO 42 - concentrations are between 5 M and 97 M in the 1980 s, then increase to between 335 M and 815 M in 2000 -2001. In 2007 the concentrations remain between 348 M and 590 M. • Seasonal trends are apparent and are related to human activities and flow variations. • Cl- concentrations in the Big Darby are between 564 M and 874 M in the late 1960 s. The concentrations increase to over 1000 M by 1992 and drastically increase in 2007 up to the highest concentration of 2274 M. • Increase in SO 42 - over time. • Increase in Cl- since the 1970 s. • F- m concentrations in the Little Darby stay relatively constant throughout all historical data. • NO 3 - relatively constant, but the seasonal variability is greater than the long term variability. • NO 3 - concentrations reached a maximum in October of 1965 and have since remained under half of that concentration, in the Big Darby Creek. In the Little Darby Creek, NO 3 - concentrations reached a minimum of 3 M in September of 2000 and a maximum of 815 M in April of 2001. • Many different human activities can contribute Cl- and SO 42 - to aquatic systems, therefore they are good indications either of general human disturbance in the watershed or of population density. • Kaushal et al. (2005) have demonstrated that Cl- concentrations have been increasing at high rates in northeast USA streams due to de-icing operations. The application of de-icing salt Cl- in Ohio averages about 310 X 103 M km-2 yr-1(Jackson and Jobbagy, 2005). Gardner and Carey (2004) have demonstrated that in Columbus, winter additions of road salt onto highways are observed influencing Cl concentrations in the Olentangy River throughout the calendar year. • Samples collected every two weeks at the Big Darby Creek, and a tributary, the Little Darby (Figure 1) • Filtered through 0. 4 m Nuclepore membrane filters using prewashed plastic filtration towers Anions in Big Darby Creek, Darbydale, Ohio Cl, µM • Relative standard deviation for F-, Cl-, NO 3 -, and SO 42 - were 5%, 2%, and 1%, respectively N-NO 3, µM F, µM 2500 2000 Concentration (µM) • Analyzed for major anions using the ion chromatograph(IC) 1500 1000 Cl, µM 0 02 -2003 04 -2003 06 -2003 Values of Anions in Little Darby, West Jefferson, Ohio F, µM SO 4, µM F, µM 1200 400 300 Concentration (µM) 500 SO 4, µM • Kelly et al. (2008) have observed an annual increase of about 40 M L-1 in chloride in rural streams in southeast New York state between 1985 -2005 (from about ~340 M to 1125 M L-1 ). These authors estimate that 83% of this increase is due to road de-icing salt. 1000 900 800 700 600 500 400 300 800 600 500 300 100 100 09 -1996 10 -1996 12 -1996 02 -1997 03 -1997 Time • Look for more historic chemical data 400 200 07 -1996 6. Future Goals 700 200 0 05 -1996 N-NO 3, µM • For comparison in the Scioto River, the Cl- concentrations range from 577 to 2410 M L-1 with the highest concentrations observed in the late summer and the lowest in the spring (Carey and Lyons, unpublished). Nitrate concentrations in the Scioto range from 19 -474 M L-1 with the lowest concentrations in the late summer and the highest in the late winter/spring period (Carey and Lyons, unpublished). 1100 200 0 12 -1964 06 -1970 12 -1975 06 -1981 11 -1986 05 -1992 11 -1997 05 -2003 10 -2008 Time Cl, µM • Photographs were taken by Sarah Fortner • Nowhere in the Darby system, however, does the concentration reach 7000 M L-1, the recommended upper limit for the protection of freshwater life. 1200 1000 900 600 N-NO 3, µM 1100 1000 700 Cl, µM 1200 1100 800 09 -2003 Values of Anions in Little Darby, West Jefferson, Ohio Concentration (µM) N-NO 3, µM 07 -2003 Time Values of Anions in Little Darby, West Jefferson, Ohio Concentration (u. M) • Below is the view downstream of the Big Darby Creek in Darbydale 500 Time Cl, µM • Above is the downstream view of Little Darby Creek in West Jefferson SO 4, µM 1000 0 09 -1961 06 -1964 03 -1967 12 -1969 09 -1972 06 -1975 03 -1978 11 -1980 08 -1983 05 -1986 F, µM N-NO 3, µM 1500 Figure 1 Pictures Anions in Big Darby Creek, Darbydale, Ohio 0 02 -2003 04 -2003 06 -2003 07 -2003 09 -2003 • Determine SO 42 - sources Time • Gather discharge rate data 4. Seasonal Variation from 2007 Acknowledgements • F- concentrations are the lowest of all anions, ranging from 16. 8 M to 31. 6 M in the Little Darby and 17. 3 M to 30. 9 M in the Big Darby. Thank you to Sarah Fortner, Chris Gardner, Kathy Welch, and Rebecca Witherow. • NO 3 - concentration decreases from 289 M to 9 M in the spring to the summer and then increases to 265 M in autumn in the Big Darby river. In the Little Darby Creek NO 3 - concentrations decrease from 314 M to 10 M. • SO 42 - increases steadily from 365 M to 590 M in the Little Darby, and from 374 M to 1063 M in the Big Darby. • Cl- concentrations increase overall in the Big Darby Creek from 772 M to 2274 M. In the Little Darby they fluctuate between 671 M and 819 M. • Retrieve population data from census records • Calculate area of pavement in watershed • Collect data of salt application volume References Big Darby Creek Land Use. Ohio EPA Division of Surface Water. http: //www. epa. state. oh. us/dsw/permits/GP_Construction. Site. Storm. Water_Darby. html, accessed 2 May 2008. Gardner, C. B. and Carey, A. E. , Trace Metal and Major Ion Inputs into the Olentangy River from an Urban Storm Sewer. Environ. Sci. Technol. 2004, 38, 5319 -5326. Jackson, R. B. and Jobbagy, E. G. , 2005 From icy roads to salty streams, Proceedings of the National Academy of Sciences, 102, 12, 487 -14, 488. Kaushal, S. S. et al. , Increased salinization of freshwater in the northeastern United States, Proceedings of the National Academy of Sciences, 102, 13, 517 -13, 520. Kelly, V. R. et al. , Long-Term Sodium Chloride Retention in a Rural Watershed: Legacy Effects of Road Salt on Streamwater Concentration. Environ. Sci. Technol. 2008, 42, 410 -415. USGS National Water Information System. Water Quality Samples for the Nation. http: //nwis. waterdata. usgs. gov/nwis/qwdata? accessed 4 May 2008.
- Slides: 1