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Long-term dispersion of contaminants in small estuaries

Published online by Cambridge University Press:  12 April 2006

Ronald Smith
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge

Abstract

It is shown that the use of axes moving with the tide (Shinohara et al. 1969) simplifies the analysis of contaminant dispersion in estuaries. Attention is restricted to estuaries which are small in the sense that cross-sectional mixing is rapid and that the tidal elevation can be taken to be constant along the estuary. In agreement with the work of Fischer (1972a, b) it is found that the dominant mechanism for dispersion is the transverse shear and not the vertical shear. Results are presented to illustrate the dependence of the upstream penetration of salt upon the estuary geometry as well as upon the fresh-water discharge rate.

Type
Research Article
Copyright
© 1977 Cambridge University Press

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References

Arons, A. B. & Stommel, H. 1951 A mixing length theory of tidal flushing. Trans. Am. Geophys. Un. 32, 419421.Google Scholar
Bowden, K. F. 1965 Horizontal mixing in the sea due to a shearing current. J. Fluid Mech. 21, 343356.Google Scholar
Bowden, K. F. 1967 Circulation and diffusion. In Estuaries (ed. G. K. Lauff), pp. 1536. Washington: A.A.A.S. Publ. no. 83.
Chatwin, P. C. 1975 On the longitudinal dispersion of passive contaminant in oscillatory flows in tubes. J. Fluid Mech. 71, 513527.Google Scholar
Chatwin, P. C. 1976 Some remarks on the maintenance of the salinity distribution in estuaries. Estuarine Coastal Mar. Sci. 4, 555566.Google Scholar
Cole, J. D. 1968 Perturbation Methods in Applied Mathematics. Waltham, Mass.: Blaisdell.
Erdogan, M. E. & Chatwin, P. C. 1967 The effects of curvature and buoyancy on the longitudinal dispersion of solute in a horizontal tube. J. Fluid Mech. 29, 465484.Google Scholar
Fischer, H. B. 1967 The mechanics of dispersion in natural streams. J. Hydraul. Div. A.S.C.E. 93, 187216.Google Scholar
Fischer, H. B. 1972a A Lagrangian method for predicting pollutant dispersion in Bolinas Lagoon, Marin County, California. U.S. Geol. Surv. Prof. Paper 582–B.
Fischer, H. B. 1972b Mass transport mechanisms in partially stratified estuaries. J. Fluid Mech. 53, 671687.Google Scholar
Fischer, H. B. 1976 Mixing and dispersion in estuaries. Ann. Rev. Fluid Mech. 8, 107133.Google Scholar
Hansen, D. V. & Rattray, M. 1965 Gravitational circulation in straits and esturaries. J. Mar. Res. 23, 104122.Google Scholar
Harleman, D. R. F. & Thatcher, M. L. 1974 Longitudinal dispersion and unsteady salinity intrusion in estuaries. Houille Blanche 29, 2533.Google Scholar
Holley, E. R. & Harleman, D. R. F. 1965 Dispersion of pollutants in estuary type flows. M.I.T. Hydrodyn. Lab. Rep. no. 74.Google Scholar
Holley, E. R., Harleman, D. R. F. & Fischer, H. B. 1970 Dispersion in homogeneous estuary flow. J. Hydraul. Div. A.S.C.E. 96, 16911709.Google Scholar
Imberger, J. 1976 Dynamics of a longitudinally stratified estuary. Proc. 15th Int. Conf. Coastal Engng, Hawaii (to appear).Google Scholar
Okubo, A. 1973 Effect of shoreline irregularities on streamwise dispersion in estuaries and other embayments. Neth. J. Sea Res. 6, 213224.Google Scholar
Shinohara, K., Tsubaki, T., Awaya, Y. & Furumoto, K. 1969 Numerical analysis on the salinity intrusion in the tidal estuary of well-mixed type. Proc. 13th Cong. I.A.H.R., Kyoto, Japan 3 165172.Google Scholar
Smith, R. 1976 Longitudinal dispersion of a buoyant contaminant in a shallow channel. J. Fluid Mech. 78, 677689.Google Scholar
Stommel, H. 1953 Computation of pollution in a vertically mixed estuary. Sewage Indust. Wastes 25, 1065–1071.
Talbot, J. W. & Talbot, G. A. 1974 Diffusion in shallow seas and in English coastal and estuarine waters. Rapp. P-v. Reun. Cons. Int. Explor. Mer. 167, 93110.Google Scholar
Taylor, G. I. 1953 Dispersion of soluble matter in solvent flowing slowly through a tube. Proc. Roy. Soc. A 219, 186203.Google Scholar