, Volume 8, Issue 2, pp 183–194 | Cite as

Identification of alluvial fans susceptible to debris-flow hazards

  • Andrew Welsh
  • Tim DaviesEmail author
Original Paper


We describe and test a method for identifying alluvial fans likely to be affected by debris flows. It is based on identifying catchment parameters by geographical information system interrogation of a digital elevation model, using the Melton ratio as the discriminating parameter. The method was calibrated using data from debris-flow-generating catchments in Coromandel and the adjacent Kaimai Ranges, North Island, NZ, and tested against data from the rest of New Zealand. The procedure is remarkably (but not completely) reliable for identifying debris-flow-capable catchments, and thus fans, across the wide range of climates and lithologies in New Zealand mountains. A case study illustrates the potential of the method for avoiding future hazards and emphasises the need for a precautionary approach when field investigations do not detect evidence for past debris flows.


Debris-flow hazards Hazard area identification GIS Catchment parameters Geomorphology 



We gratefully acknowledge support for this project from the Earthquake Commission of NZ; in-kind assistance and enthusiastic cooperation from Environment Waikato, NZ; and the geomorphic advice of Dr. M J McSaveney, GNS Science, Lower Hutt, NZ. Clive Sabel and Tom Cochrane of the University of Canterbury both provided invaluable technical advice.


  1. National Institute of Water and Atmospheric Science (2007) Accessed 8 March 2007
  2. Baum RL, Godt JW (2010) Early warning of rainfall-induced shallow landslides and debris flows in the USA. Landslides (in press). doi: 10.1007/s10346-009-0177-0
  3. Caine N (1980) The rainfall intensity–duration control of shallow landslides and debris flows. Geogr Ann 62A:23–27CrossRefGoogle Scholar
  4. Christie AB, Brathwaite RL, Rattenbury MS, Skinner DNB (2001) Mineral resource assessment of the Coromandel region, New Zealand. Science Report 2001/11, Institute of Geological and Nuclear Sciences, Lower Hutt, New ZealandGoogle Scholar
  5. Davies TRH (1988) Debris flow surges—a laboratory investigation. Mitteilung Nr 96, VAW, ETH-Zurich, Switzerland, p 122Google Scholar
  6. Davies TRH (1997) Using hydro-science and hydro-technical engineering to reduce debris-flow hazards. In: Proceedings of the First International Conference—Debris-flow Hazards Mitigation: Mechanics, Prediction and Assessment, pp 787–810, San Francisco, American Society of Civil EngineersGoogle Scholar
  7. Davies TRH, Hall RJ (1992) A realistic strategy for disaster prevention. In: Proceedings, Interpraevent 1992, Bern, Switzerland, pp 381–390Google Scholar
  8. Davies TRH, McSaveney MJ (2008) Principles of sustainable development on fans. J Hydrol NZ 47:43–65Google Scholar
  9. de Scally FA, Owens IF (2004) Morphometric controls and geomorphic response on fans in the Southern Alps, New Zealand. Earth Surf Process Land 29:311–322CrossRefGoogle Scholar
  10. de Scally FA, Slaymaker O, Owens IF (2001) Morphometric controls and basin response in the Cascade Mountains. Geogr Ann 83A:117–130CrossRefGoogle Scholar
  11. Environment Waikato (2007) Accessed 4 May 2007
  12. ESRI (2006) Arc GIS V.9.2 desktop electronic help manual.Google Scholar
  13. Finlay PJ, Fell R (1997) Landslides: risk perception and acceptance. Can Geotech J 34:169–188Google Scholar
  14. Gillon MD (2000) Current trends in assessing dam safety. In: Proceedings of Technical Groups, IPENZ, NZ Society on Large Dams, Wellington, NZ, pp 25–36Google Scholar
  15. Grant HI (1998) Late Quaternary and engineering geology of the Franz Josef area, South Westland. Unpubl. MSc thesis, University of Canterbury, New Zealand, p 218Google Scholar
  16. Iverson RM (1997) The physics of debris flows. Rev Geophys 35:245–296CrossRefGoogle Scholar
  17. Jackson LE Jr, Kostaschuk RA, MacDonald GM (1987) Identification of debris-flow hazard on alluvial fans in the Canadian Rocky Mountains. Rev Eng Geol 7:115–124Google Scholar
  18. Jakob M, Hungr O (eds) (2005) Debris-flow hazards and related phenomena. Springer, BerlinGoogle Scholar
  19. Jane TG, Green TGA (1984) Ecological aspects of climate patterns within the Kaimai Ranges, North Island, New Zealand. NZ J Ecol 7:183–197Google Scholar
  20. Klubertanz G, Laloui L, Vulliet L (2009) Identification of mechanisms for landslide type initiation of debris flows. Eng Geol 109:114–123CrossRefGoogle Scholar
  21. Kostaschuk RA, Macdonald GM, Putnam PE (1986) Depositional process and alluvial fan—drainage basin morphometric relationships near Banff, Alberta, Canada. Earth Surf Process Land 11:471–484CrossRefGoogle Scholar
  22. Maunder WJ (1970) World survey of climatology, vol 13. Elsevier, AmsterdamGoogle Scholar
  23. McSaveney MJ, Beetham RD, Leonard GS (2005) The 18 May 2005 debris-flow disaster at Matata: causes and mitigation suggestions. Client Report 2005/71, Institute of Geological and Nuclear Sciences, Lower Hutt, New ZealandGoogle Scholar
  24. Melton MA (1965) The geomorphic and paleoclimatic significance of alluvial deposits in southern Arizona. J Geol 73:1–38CrossRefGoogle Scholar
  25. Montz BE (2007) The effects of flooding on residential property values in three New Zealand communities. Disasters 16:283–298CrossRefGoogle Scholar
  26. Encyclopaedia of New Zealand (2000)
  27. Newsome PFJ (1987) The vegetative cover of New Zealand. National Water and Soil Conservation Authority, WellingtonGoogle Scholar
  28. Pierson TC (2005) Hyperconcentrated flow—transitional process between water-flow and debris-flow. In: Jakob M, Hungr O (eds) Debris-flow hazards and related phenomena. Springer, BerlinGoogle Scholar
  29. Rowbotham D, de Scally F, Louis J (2005) The identification of debris torrent basins using morphometric measures derived within a GIS. Geogr Ann 87A:527–537CrossRefGoogle Scholar
  30. Takahashi T (1981) Estimation of potential debris flows and their hazardous zones: soft countermeasures for a disaster. J Nat Disaster Sci 3:57–89Google Scholar
  31. Welsh AJ (2008) Delineating debris-flow hazards on alluvial fans in the Coromandel and Kaimai regions, New Zealand using GIS. MSc thesis, University of Canterbury, New Zealand, 169p + AppGoogle Scholar
  32. Wilford DJ, Sakal ME, Innes JL, Sidle RC, Bergerud WA (2004) Recognition of debris-flow, debris-flood and flood hazard through watershed morphometrics. Landslides 1:61–66CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.BrisbaneAustralia
  2. 2.Geological SciencesUniversity of CanterburyCanterburyNew Zealand

Personalised recommendations