Environmental Management

, Volume 9, Issue 1, pp 35–48 | Cite as

Channel change, sediment transport, and fish habitat in a coastal stream: Effects of an extreme event

  • Robert Coats
  • Laurel Collins
  • Joan Florsheim
  • Darrell Kaufman


A study on sediment transport and channel change was conducted on Zayante Creek and the lower San Lorenzo River in Santa Cruz County, California. A rainstorm with a recurrence interval locally in excess of 150 years occurred during the study year, 1982 WY. Stream surveys indicated that significant aggradation occurred during and after the peak flood. Upper study reaches were substantially recovered after high flows of early April, but the lower study reaches still had significant filling of pools and burial of riffles by sand. Increases in width-depth ratio were minor and localized in upper reaches, but were significant in lower reaches. Large inputs of sand, primarily from landsliding, altered the sediment transport regime. A higher proportion of the bedload is now transported by lower flows than before the January event. Roads and sand quarries contributed significantly to sediment input to the stream. A proposed dam may alter the sediment transport regime of Zayante Creek. Mitigating the effects of this dam on downstream fish habitat may require occasional bankfull discharges.

Key words

Channel change Sediment transport Fish habitat Flood effects Geomorphic effectiveness 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Literature cited

  1. Bjornn, T. C., M. A. Brusven, M. P. Molnau, J. H. Milligan, R. A. Klant, E. Chacho, and C. Schaye. 1977. Transport of granitic sediment in streams and its effects on insects and fish. University of Idaho Forest, Wildlife and Range Experiment Station Bulletin 17. 43 pp.Google Scholar
  2. Brown, W. M. III. 1973. Erosion processes, fluvial sediment transport and reservoir sedimentation in a part of the Newell and Zayante Creek basins, Santa Cruz County, California. Open file report. US Geological Survey, Menlo Park. 31 pp.Google Scholar
  3. Clark, J. C. 1981. Stratigraphy, paleontology, and geology of the Central Santa Cruz Mountains, California Coast Ranges. US Geological Survey. Professional paper 1168. 51 pp.Google Scholar
  4. Coats, R. N., and L. Collins. 1984. Streamside landsliding and channel change in a suburban forested watershed: effects of an extreme event.In Proceedings of symposium on effects of forest land use on erosion and slope stability. International Union of Forestry Research Organizations, Honolulu. New Zealand Forest Service Forest Research Institute, Christchurch, New Zealand (in press).Google Scholar
  5. Dietrich, W. E., T. Dunne, N. F. Humphrey, and L. M. Reid. 1982. Construction of sediment budgets for drainage basins. Pages 5–23in F. Swanson, R. Janda, T. Dunne, and D. N. Swanston (eds.), Sediment budgets and routing in forested drainage basins. USDA Forestry Service Pacific NW Forest and Range Experiment Station general technical report PNW-141. Corvallis, OR.Google Scholar
  6. Goodridge, J. D. 1980. California rainfall summary: monthly total precipitation. California Department of Water Resources, Sacramento.Google Scholar
  7. Goodridge, J. D. 1981. Rainfall depth-duration-frequency for California. California Department of Water Resources, Sacramento.Google Scholar
  8. Griggs, G. B. 1982. Flooding and slope failure during the January 1982 storm, Santa Cruz County, California.California Geology 35:158–163.Google Scholar
  9. Hecht, B., and R. Enkeboll. 1981. Channel and substrate conditions, sediment transport and alternative approaches for sediment management in Zayante Creek below proposed Zayante Dam.In H. Esmaili and Associates, Final report. Berkeley, CA. 93 pp.Google Scholar
  10. Henderson, F. M. 1966. Open channel flow. Macmillian, New York. 522 pp.Google Scholar
  11. Jackson, W. L. 1981. Bed material routing and streambed composition in alluvial channels, PhD thesis, Oregon State University. 160 pp.Google Scholar
  12. Keller, E., A. MacDonald, and Taz Tally. 1982. Streams in the Coastal Redwood environment: the role of large organic debris. Pages 161–176In R. Coats (ed.), Watershed rehabilitation in Redwood National Park and other Pacific coastal areas. Symposium Proceedings. Center for Natural Resource Studies, Berkeley, CA.Google Scholar
  13. Lisle, T. E. 1982. Channel recovery from recent large floods in North Coastal California: rates and processes. Pages 153–160in R. N. Coats (ed.), Watershed rehabilitation in Redwood National Park and other Pacific coastal areas. Symposium proceedings, Center for Natural Resource Studies, Berkeley, CA.Google Scholar
  14. Mark, R. K., E. B. Newman, C. R. Northcut, and B. R. Hamachi. 1983. Rainfall associated with the January 1982 rainstorm in the San Francisco Bay Region, California. Open file map OF-83-16. US Geological Survey. Menlo Park, CA.Google Scholar
  15. Newson, M. 1980. The geomorphological effectiveness of floods: a contribution stimulated by two recent events in Mid-Wales.Earth Surface Processes 5:1–16.Google Scholar
  16. Nolan, K. M., D. Marron, and L. Collins. 1983. Stream channel response to the January 3–5, 1982, storm in the Santa Cruz Mountains, West Central California. US Geological Survey open file report. Menlo Park, CA. 54 pp.Google Scholar
  17. Santa Cruz County Planning Department. 1979. The San Lorenzo River watershed management plan. Santa Cruz County Planning Department and State of California Resources Agency. 235 pp.Google Scholar
  18. Stanley, J. T., J. J. Smith, D. W. Alley, D. Matias, and B. Elsey. 1982. Fish habitat assessments for Santa Cruz County streams. Harvey and Stanley Associates, Alviso, CA 74 pp.Google Scholar
  19. Water Resources Council. Guidelines for determining flood flow frequency. 1982. Bulletin 17B of the Hydrology Subcommittee. US Department of the Interior Geological Survey. Office of Water Data Coordination, Reston, VA.Google Scholar
  20. Wolman, M. G. 1954. A method of sampling coarse riverbed material.American Geophysical Union Transactions 35:951–956.Google Scholar
  21. Wolman, M. G., and R. Gerson. 1978. Relative scales of time and effectiveness of climate in watershed geomorphology.Earth Surface Processes 3:189–208.Google Scholar
  22. Wolman, M. G., and J. P. Miller. 1960. Magnitude and frequency of forces in geomorphic processes.Journal of Geology 68:54–74.Google Scholar

Copyright information

© Springer-Verlag New York Inc. 1985

Authors and Affiliations

  • Robert Coats
    • 1
  • Laurel Collins
    • 1
  • Joan Florsheim
    • 1
  • Darrell Kaufman
    • 1
  1. 1.Center for Natural Resource StudiesBerkeleyUSA

Personalised recommendations