Human activity has affected profoundly streams and lakes in all parts of the world. Streams have been subjected to additions of gross amounts of domestic sewage, industrial effluents (e.g., wastes from tanneries, pulp mills, creameries, steel mills, and chemical factories), agricultural wastes, oil spills, mining wastes, urban runoff, radioactive materials, pesticides, waste heat, and numerous other pollutants, often because it was considered expedient and economical to have the unwanted materials carried away (“out of sight”) by the flowing water. Likewise, under the guise of “progress,” streams have been channelized, stabilized, de watered (for irrigation), and super-watered (artificially increased flow for drinking and power plant needs). In most cases, the effects on the aquatic biota are insidiously cumulative. In some cases, the effects are readily apparent [e.g., acid mine drainage; see Parsons (1986)], but in others the effects accumulate more slowly [e.g., accumulations of trace metals; see Whitton and Say (1975)]. In all cases, a longitudinal gradient develops below the point of insult and, given enough time (distance) without further insult, the stream ecosystem generally recovers to a state of well-being.
In this exercise, we shall examine the effects of a sewage outfall on a stream ecosystem. Select a site, preferably on a small stream, into which sewage is being discharged. In most areas of the United States, this sewage will have already undergone primary and/or secondary treatment [e.g., Bolton and Klein (1971) and Rohlich and Uttormark (1972)]. Nevertheless, exercise health precautions when collecting and analyzing samples from such areas; for example, keep hands away from face and wash thoroughly after handling samples. Select sample sites immediately above and below the sewage outfall. In addition, a few sites 1km apart above and 2 km apart below the outfall should delineate the longitudinal changes.
KeywordsAcid Mine Drainage Domestic Sewage American Public Health Association Pulp Mill Coliform Bacterium
Unable to display preview. Download preview PDF.
- American Public Health Association. 1998. Standard Methods for the Examination of Water and Wastewater. 20th Ed. Water Environment Federation, Alexandria, VA. 1510 pp.Google Scholar
- Bertucci, J.J., C. Lue-Hing, D. Zenz, and S.J. Sedita. 1977. Inactivation of viruses during anaerobic sludge digestion. J. Water Poll. Control. Fed. 49:1624–1651.Google Scholar
- Bolton, R.L. and L. Klein. 1971. Sewage Treatment—Basic Principles and Trends. Ann Arbor Publ. Michigan. 256 pp.Google Scholar
- Borchardt, J.A., J.K. Cleland, W.J. Redman, and G. Oliver (eds). 1977. Viruses and Trace Contaminants in Water and Wastewater. Ann Arbor Sci. Publ., Michigan. 249 pp.Google Scholar
- Hammer, D.A. 1997. Creating Freshwater Wetlands. 2nd Ed. Lewis Publishers, Boca Raton, FL. 406 pp.Google Scholar
- Hanes, N.B., G.A. Delaney, and C.J. O’Leary. 1965. Relationship between Escherichia coli, Type I, coliform and enterococci in water. J. Boston Soc. Civil Engrs. 52:129–140.Google Scholar
- Hynes, H.B.N. 1963. The Biology of Polluted Waters. Liverpool Univ. Press. 202 pp.Google Scholar
- Kadlec, R.H. and R.L. Knight. 1997. Treatment Wetlands. Lewis Publishers, Boca Raton, FL. 893 pp.Google Scholar
- Likens, G.E. (ed). 1972. Nutrients and Eutrophication. Special Symposia, Vol. I. Amer. Soc. Limnol. Oceanogr., Allen Press, Lawrence, KS. 328 pp.Google Scholar
- Parsons, J.D. 1968. The effects of acid strip-mine effluents on the ecology of a stream. Arch. Hydrobiol. 65:25–50.Google Scholar
- Rodina, A.G. 1972. Methods in Aquatic Microbiology. Translated and revised by R.R. Colwell and M.S. Zambruski. Univ. Park Press, Baltimore. 461 pp.Google Scholar
- Rohlich, G.A. and P.D. Uttormark. 1972. Wastewater treatment and eutrophication. pp. 231–245. In: G.E. Likens, Editor. Nutrients and Eutrophication. Special Symposia, Vol. I. Amer. Soc. Limnol. Oceanogr. Allen Press, Lawrence, KS.Google Scholar
- Whitton, B.A. and P.J. Say. 1975. Heavy metals, pp. 286–311. In: B.A. Whitton, Editor. River Ecology. Univ. of California Press, Berkeley.Google Scholar