Shoreline Erosional-Depositional Processes Associated with Tidal Inlets

  • Duncan M. FitzGerald
Conference paper
Part of the Lecture Notes on Coastal and Estuarine Studies book series (COASTAL, volume 29)


Tidal inlets strongly influence the overall dynamics of barrier island shorelines. The average barrier length along a coast is controlled by the size and number of tidal inlets, which in turn, are primarily a function of a region’s tidal range and bay area. The greatest magnitude erosional-depositional changes along a barrier chain occur next to tidal inlets, and these losses and gains of sand are a direct consequence of tidal inlet processes. During a transgression, as at present, ephemeral, migrating and stable inlets provide a means for transferring a large proportion of the coastal sand reserves landward past the eroding shoreline. This is accomplished through the transport of sand to flood-tidal deltas, tidal creeks and the marsh surface, and through the building of recurved spits.

Ebb-tidal deltas represent a large sand reservoir which may be comparable in volume to that of the adjacent barrier islands. Slight changes in the size of an ebb delta, due to changes in the inlet tidal prism, can greatly affect the sand supply to nearby beaches. The sand shoals associated with ebb-tidal deltas may act as natural offshore breakwaters, reducing wave energy on landward beaches. Their removal may cause or accelerate shoreline erosion.

Along mixed energy shorelines inlet sediment bypassing occurs by three major mechanisms: 1. inlet migration and spit breaching, 2. stable inlet processes, and 3. ebb-tidal delta breaching. Migrating tidal inlets tend to have relatively shallow inlet channels that erode through non-resistant sediments. Spit breaching is an uncommon event, but its occurrence results in the bypassing of large amounts of sand. In the other two methods of bypassing, large bar complexes are formed on the downdrift side of the ebb-tidal delta. These bars, which may be over 1 km long and may contain more than 500,000 m3of sand, migrate onshore welding to the landward beach. The process of bar attachment dictates the shape of many barriers.


Tidal Range Barrier Island Shoreline Change Tidal Inlet Tidal Prism 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Armon, J.W., 1979. Landward sediment transfers in a transgressive barrier island system, Canada. In: Leatherman, S.P. (ed.), Barrier Islands. Academic Press, New York, p. 65–80.Google Scholar
  2. Ashley, G.M., Halsey, S.D. and Farrell, S.C., 1987. A study of beach fill longevity: Long Beach, NJ. Coastal Sediments 1987, Amer. Soc. of Civil Engr., p. 1188 – 1202.Google Scholar
  3. Aubrey, D.G. and Gaines, A.G., 1982. Recent evolution of an active barrier beach complex: Popponesset Beach, Cape Cod, MA.CrossRefGoogle Scholar
  4. Aubrey, D.G. and Speer, P.E., 1984. Updrift migration of tidal inlets. J. Geology, 92: 531–546.CrossRefGoogle Scholar
  5. Bartberger, CE., 1976. Sediment sources and sediementation rates, Chincoteague Bay, MD and VA. J. Sed. Petrology, 78:326–336.Google Scholar
  6. Boothroyd, J.C. and Hubbard, D.K., 1975. Genesis of bedforms in mesotidal estuaries. In: Cronin, L.E. (ed.), Estuarine Research. Academic Press, New York, 2:217 – 235.Google Scholar
  7. Brown, P.J., 1976. Variations in South Carolina coastal morphology. In: Hayes, M.O., and Kana, T.W. (eds.), Terrigenous Clastic Depositional Environments. Tech. Rpt. No. 11-CRD, Dept. of Geology, Univ. of South Carolina, p. 2–15.Google Scholar
  8. Bruun, P. and Gerritsen, F., 1959. Natural bypassing of sand at coastal inlets. J. Waterways and Harbors Div., 85:75–107.Google Scholar
  9. Cleary, WJ. and Hosier, P.E., 1987. Onslow Beach, NC: morphology and stratigraphy. Coastal Sediments 1987, Amer. Soc. of Civil Engr., p. 1745–1759.Google Scholar
  10. Cleary, WJ., Hosier, P.E. and Well, G.R., 1979. Genesis and significance of marsh islands within southeastern North Carolina lagoons. J. Sed. Petrology, 49:703 – 710.Google Scholar
  11. Czerniak, M.T., 1977. Inlet interaction and stability theory verification. Coastal Sediments 1977, Amer. Soc. of Civil Engr., p. 754–773.Google Scholar
  12. Davies, J.L., 1964. A morphogenic approach to world shorelines. Zeit, für Geomorph., 8:27–42.Google Scholar
  13. Davis, R.A. and Fox, W.T., 1980. Interaction between wave and tide generated processes at the mouth of a mesotidal estuary: Matanzas River, Florida. Marine Geol., 40:49–68.CrossRefGoogle Scholar
  14. Dealteris, J.T. and Byrne, R.J., 1975. The recent history of Wachapreague Inlet, VA. In: Cronin, L.E. (ed.), Estuarine Research. Academic Press, New York, 2:167–181.Google Scholar
  15. Dean, R.G. and Perlin, M., 1977. Coastal engineering study of Ocean City Inlet, MD. Coastal Sediments 1977, Amer. Soc. of Civil Engr., p. 520–542.Google Scholar
  16. Dolan, R. and Glassen, R., 1972. Oregon Inlet, NC: a history of coastal change. Southeastern Geographer, 13:41–53.Google Scholar
  17. Escoffier, F.F., 1940. The stability of tidal inlets. Shore and Beach, 8:114–115.Google Scholar
  18. Fitzgerald, D.M., 1981. Patterns of shoreline changes along Atlantic City Beach caused by Absecon Inlet processes. Tech. Rpt. No. 6, Coastal Environmental Research Group, Dept. of Geology, Boston University, 60 pp.Google Scholar
  19. Fitzgerald, D.M., 1982. Sediment bypassing at mixed energy tidal inlets. 18thCoastal Engr. Conf., Amer. Soc. of Civil Engr., p. 1094–1118.Google Scholar
  20. Fitzgerald, D.M., 1984. Interactions between the ebb-tidal delta and landward shoreline: Price Inlet, SC. J. Sed. Petrology, 54:1303–1318.Google Scholar
  21. Fitzgerald, D.M., 1985. Effects of the Bay of Fundy Project on the tidal inlets in Maine. New England Regional Coastal Engr. Conf., U.S. Army Corps of Engr., p. 74 – 78.Google Scholar
  22. Fitzgerald, D.M., Baldwin, CT., Ibrahim, N.A., and Sands, D.R., 1987. Development of the northwestern Buzzards Bay shoreline, MA. In: Fitzgerald, D.M. and Rosen, P.S. (eds.), Glaciated Coasts. Academic Press, New York, (in press).Google Scholar
  23. Fitzgerald, D.M., Fico, C. and Hayes, M.O., 1979. Effects of the Charleston Harbor, SC jetty construction on local accretion and erosion. Coastal Structures 1979, Amer. Soc. of Civil Engr., p. 641–664.Google Scholar
  24. Fitzgerald, D.M. and Fink, L.K., 1987. Sediment dynamics along an indented coast:Popham Beach-Kennebec River, ME. Coastal Sediments 1987, Amer. Soc. of Civil Engr., p. 2047–2061.Google Scholar
  25. Fitzgerald, D.M., Fink, L.K. and Lincoln, J., 1983. A flood dominated mesotidal inlet. Geo-Marine Letters, 3:17–22.CrossRefGoogle Scholar
  26. Fitzgerald, D.M. and Hayes, M.O., 1980. Tidal inlet effects on barrier island management. Coastal Zone 1980, Amer. Soc. of Civil Engr., p. 2355–2379.Google Scholar
  27. Fitzgerald, D.M. and Levin, D., 1981. Hydraulics, morphology and sediment transport patterns at Pamet River Inlet: Truro, MA. Northeast Geol., 3:216–224.Google Scholar
  28. Fitzgerald, D.M., Hubbard, D.K. and Nummedal, D., 1978. Shoreline changes associated with tidal inlets along the South Carolina coast. Coastal Zone 1978, Amer. Soc. of Civil Engr., p. 1973–1994.Google Scholar
  29. Fitzgerald, D.M., Nummedal, D. and Kana, T.W., 1976. Sand circulation patterns at Price Inlet, SC. 15thCoastal Engr. Conf., Amer. Soc. of Civil Engr., p. 1868–1880.Google Scholar
  30. Fitzgerald, D.M., Penland, S. and Nummedal, D., 1984a. Changes in tidal inlet geometrydue to backbarrier filling: East Friesian Islands, West Germany. Shore and Beach, 52:3–8.Google Scholar
  31. Fitzgerald, D.M., Penland, S. and Nummedal, D., 1984b. Control of barrier island shape by inlet sediment bypassing: East Friesian Islands, West Germany. Marine Geology, 60:355–376.CrossRefGoogle Scholar
  32. Fitzgerald, D.M., Saiz, A., Baldwin, C.T. and Sands, D.R., 1986. Spit breaching at Slocum River Inlet: Buzzards Bay, MA. Shore and Beach, 54:11–17.Google Scholar
  33. Hales, L.Z. and Herbich, J.B., 1972. Tidal inlet current-ocean interaction. 13thCoastal Engr. Conf., Amer. Soc. of Civil Engr., p. 679–688.Google Scholar
  34. Hanisch, J., 1981. Sand transport in the tidal inlet between Wangerooge and Spiekeroog: West Germany. Spec. Pub. Int. Assoc. Sed., 5:175–185.Google Scholar
  35. Hayes, M.O., 1975. Morphology of sand accumulations in estuaries. In: Cronin, L.E. (ed.), Estuarine Research. Academic Press, New York, 2:3–22.Google Scholar
  36. Hayes, M.O., 1979. Barrier island morphology as a function of tidal and wave regime. In: Leatherman, S. P. (ed.), Barrier Islands: From the Gulf of St. Lawrence to the Gulf of Mexico. Academic Press, New York, p. 1–28.Google Scholar
  37. Hayes, M.O., Fitzgerald, D.M. and Hubbard, D.K., 1978. Tidal inlet control of beach erosion-depositional cycles. Amer. Shore and Beach Pres. Assoc, Proc. 5thAnnual Meeting, Tallahassee, FL, p. 121–140.Google Scholar
  38. Hayes, M.O. and Kana, T.W., 1976. Terrigenous Clastic Depositional Environment.Tech. Rpt. No. CRD-11, Dept. of Geology, Univ. of South Carolina, Columbia, SC, 364 pp.Google Scholar
  39. Hine, A.C., 1972. Sand deposition in the Chatham Harbor Estuary and on neighboring beaches, Cape Cod, MA. Unpub. Masters Thesis, Dept. of Geology, Univ. of Massachusetts, Amherst, MA, 187 pp.Google Scholar
  40. Hine, A.C., 1975. Bedform distribution and migration patterns on tidal deltas in the Chatham Harbor Estuary, Cape Cod, MA. In: Cronin, L.E. (ed.), Estuarine Research. Academic Press, New York, 2:235–252.Google Scholar
  41. Hine, A.C., Snyder, S.S. and Nuemann, A.C., 1979. Coastal plain and inner shelf structure, stratigraphy and geologic history: Bogue Bank area, NC. Tech. Rpt. North Carolina Sei. Technology Comm., Chapel Hill, NC, 67 pp.Google Scholar
  42. Homeier, H. and Luck, G., 1969. Das Historische Kartenwerk 1:50,000 der Niedersächsischen Wasserwirtchafsverwaltung, Guttingen.Google Scholar
  43. Hubbard, D.K., Barwis, J.H. and Nummedal, D., 1977. Sediment transport in four South Carolina inlets. Coastal Sediments 1977, Amer. Soc. of Civil Engr. p. 582–601.Google Scholar
  44. Johnson, J.W., 1919. Shore Processes and Shoreline Development. John Wiley and Sons, New York, 584 pp.Google Scholar
  45. Kochel, C, Kahn, J.H., Dolan, R., Hayden, B.P. and May, P.F., 1985. U.S. Mid- Atlantic barrier island morphology. Coastal Research, 1:1–9.Google Scholar
  46. Kumar, N. and Sanders, J.E., 1974. Inlet sequences: a vertical succession of sedimentary structures and textures created by the lateral migration of tidal inlets. Sedimentology, 21:291–323.CrossRefGoogle Scholar
  47. Langfelder, J., Stafford, D. and Amein, M., 1968. A reconnaisance of coastal erosion in North Carolina. Tech. Rpt., ERD-238, Dept. of Civil Engr., N.C. State Univ., Raleigh, NC, 219 pp.Google Scholar
  48. Larson, P.F. and Topinka, J.A., 1984. Fundy tidal power development. Tech. Rpt. to Maine State Planning Office, Augusta, ME, 136 pp.Google Scholar
  49. Leatherman, S.P., 1984. Shoreline evolution of north Assateague Island, MD. Shore and Beach, 52:3–10.Google Scholar
  50. Lincoln, J.M. and Fitzgerald, D.M., 1988. Tidal distortions and flood dominance at five small inlets in Maine. Marine Geology, (in press).Google Scholar
  51. Luck, G., 1975. Der Einfluss der Schutzwerke der ostfriesischen Inseln auf die morphologischen Vorgange im Bereich der Seegaten und ihre Einzugsgebeite. Mitt. Leichtweiss Inst., Braunschweig, 47:1–22.Google Scholar
  52. Luck, G., 1976. Inlet changes of the East Friesian Islands. 15thCoastal Engr. Conf., Amer. Soc. of Civil Engr., p. 1938–1957.Google Scholar
  53. Lücke, J.B., 1934. A theory of the evolution of lagoon deposits on shorelines of emergence. J. Geology, 42:561–584.CrossRefGoogle Scholar
  54. Lynche-Blosse, M.A. and Davis, R.A., 1977. Stability of Dunedin and Hurricane Passes, FL. Coastal Sedrments 1977, Amer. Soc. of Civil Engr., p. 774–789.Google Scholar
  55. Morton, R.A. and Donaldson, A.C., 1973. Sediment distribution and evolution of tidal deltas along a tide-dominated shoreline, Wachapreague, Virginia. Sedimentary Geology, 10:285–299.CrossRefGoogle Scholar
  56. Moslow, T.F. and Herron, D.S., 1978. Relict inlets: preservation and occurrence in the Holocene stratigraphy of southern Core Banks, NC. J. Sed. Petrology, 48:1275 – 1286.Google Scholar
  57. Moslow, T.F. and Tye, R.S., 1988. Preservation of tidal inlet deposits along mixed energy versus wave-dominated shorelines: J. Canadian Petrol. Geol., (in press).Google Scholar
  58. Nummedal D. and Fischer, I., 1978. Process-response models for depositional shorelines: the German and Georgia Bights. Amer. Soc. of Civil Eng., Proc. 16thCoastal Eng. Conf., p. 1215–1231.Google Scholar
  59. Nummedal, D. and Penland, S., 1981. Sediment dispersal in Norderneyer Seegat, West Germany. Sedimentology, 5:187–210.Google Scholar
  60. O’Brien, M.P., 1931. Estuary tidal prisms related to entrance areas. Civil Engr., 1:738 – 739.Google Scholar
  61. O’Brien, M.P., 1969. Equilibrium flow areas of inlets on sandy coasts. J. Waterways, Harbors, and Harbors Div., 13thCoastal Engr. Conf., p. 761–780.Google Scholar
  62. Oertel, G.F., 1972. Sediment transport of estuary entrance shoals and the formation of swash platforms. J. Sed. Petrology, 42:857–863.Google Scholar
  63. Oertel, G.F., 1975. Ebb-tidal deltas of Georgia estuaries. In: Cronin, L.E. (ed.), Estuarine Research. Academic Press, New York, 2:267–276.Google Scholar
  64. Oertel, G.F., 1977. Geomorphic cycles in ebb deltas and related patterns of shore erosion and accretion. J. Sed. Petrology, 47:1121–1131.Google Scholar
  65. Oertel, G.F., 1979. Barrier island development during the Holocene recession, southeastern United States. In: Leatherman, S. P. (ed.), Barrier Islands: From the Gulf of St. Lawrence to the Gulf of Mexico. Academic Press, New York, p. 273 – 290.Google Scholar
  66. Pierce, J.W., 1970. Tidal inlets and washover fans. J. Geology, 78:230–234.CrossRefGoogle Scholar
  67. Reddering, J.S.V., 1983. An inlet sequence produced by migration of a small microtidal inlet against longshore drift: Keurbooms Inlet, South Africa. Sedimentology, 30:201–218.CrossRefGoogle Scholar
  68. Rice, T., Niedoroda, A. and Pratt, A., 1976. Coastal processes and geology, Virginiabarrier islands, on Virginia Coast Reserve Study: Ecosystem Description. TheNature Conservancy, Arlington, VA, p. 109–382.Google Scholar
  69. Sexton, W.J. and Hayes, M.O., 1982. Natural bar-bypassing (sic) of sand at a tidal inlet. 18thCoastal Engr. Conf., Amer. Soc. of Civil Engr., p. 1479–1495.Google Scholar
  70. Suter, J.R., Berryhill, H.L. and Penland, S., 1985. Environments of sand, southwest Louisiana continental shelf. Trans. Gulf Coast Assoc. Geol. Soc., 35:34–53.Google Scholar
  71. Thompson, E.F., 1977. Wave climate at selected locations along U.S. coasts. Tech. Rpt. No. 77–1, C.E.R.C., U.S. Army Corps of Engr., Washington, D.C., 364 pp.Google Scholar
  72. U.S. Army Corps of Engr., 1966. Technical report of beach erosion control, Folly Beach, Charleston, SC, 67 pp.Google Scholar
  73. Walton, T.L. and Adams, W.D., 1976. Capacity of inlet outer bars to store sand. 15thCoastal Eng. Conf., Amer. Soc. of Civil Eng., p. 1919–1937.Google Scholar

Copyright information

© Springer Science+Business Media New York 1988

Authors and Affiliations

  • Duncan M. FitzGerald
    • 1
  1. 1.Department of GeologyBoston UniversityBostonUSA

Personalised recommendations