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  • Data collection for Georges Bay, St. Helens, Tasmania
    (1984) Foster, D.N.; Cook, R.A.; Cox, R.J.
    Report
  • Analysis of pipe tests. August 1989.
    (1989) Fietz, T. R.; Higgs, K. B.
    Report
    Analysis of pipe tests to determine friction coefficients and their uncertainty is discussed. Optimisation methods are applied to finding the pipe diameter, friction coefficient and fitting loss coefficient from a pipe test. A FORTRAN program implementing these methods is included.
  • Hydraulic investigations into decanting from IEA wastewater treatment plants. Part 2: further investigations. April 1989.
    (1989) Witheridge, G. M.; Wilkinson, D. L.
    Report
    Describes an investigation into the mechanisms responsible for sludge carry-over during decant from intermittent aeration tanks. Several mechanisms were identified which may cause sludge carry-over. An "early failure" mode may occur during the transient phase at the start of decant. This can be avoided by gradually increasing the rate of decant to a final steady value. The time required for flow establishment is in the order of five minutes in tanks of current size. Following the transient phase, failure can occur when interfacial shear stresses between the supernatant and settled sludge exceed some critical value. This is considered to be a "scour failure" analagous to the onset of erosion of a cohesive sediment. Experiments conducted in a variety of different types of extended aeration tanks indicated that the critical parameters governing failure are the upstream velocity of the supernatant, the settlement time, and the Stirred Sludge Volume Index, SSVI. Appreciation of the failure mechanisms has indicated certain design improvements which could be made to existing aeration tanks, in particular to the rate of changee of weir loading and the design of scum barriers. The significance of tank depth is also discussed.
  • General runoff routing model computer programs and user guide.
    (1987) Boyd, Michael J.; Bates, Bryson C.; Pilgrim, David H.; Cordery, Ian
    Report
  • Periodic Starting Flows
    (1986) Tomlinson, R. B.
    Report
  • Tidal hydraulics of Botany Bay. March 1980.
    (1980) Lawson, N. V.; Jenkins, B. S.; Treloar, P. D.; Higgs, K.; Foster, D. N.
    Report
    Tidal currents in Botany Bay and its rivers have been examined to to assess tidal action and the effect on water movement of dredging works. Data are derived from collections and models, and the probable effects of further work is estimated. Volume 1 (paper) describes the methods , data summary and discussion. Microfiche (3) Appendix A, Prtotype data. Volume 2 pdf files. Appendix b c-d pdf files contain detailed data.
  • The Rescaled adjusted range in hydrologic design. June 1980.
    (1980) Lee, M. O.
    Report
    The findings of H. E. Hurst have profoundly affected data synthesis and reservoir development. The Hurst effect is now a feature of modelling time series. This study identifies some areas of misunderstanding of the phenomenon and results are given to support two underlying hypotheses: the rescaled adjusted range statistic is capable of measuring characteristics of practical importance; and n the basis of testing, simple generation models are suitable for many natural time series.