A methodology for the effective evaluation of the performance of wastewater systems

  • Mark Petrie

    Student thesis: Doctoral Thesis


    An integrated methodology (WISPS) has been developed and presented which addresses areas of concern associated with the performance and rehabilitation of wastewater catchments. The methodology seeks to achieve effective solutions and to ease the decision making process when faced with multi-criteria problems. The methodology has been partly applied to the study catchment and others as means of testing the product of the research work. Through the application new information is presented in the form of value functions associated with the areas of concern under evaluation.

    Holistic computer modelling of drainage catchments may seem theoretically viable but the work carried out has highlighted that there are severe limitations associated with sewer flow quality models and their ability to represent the behaviour of pollutants within sewerage systems. While UPM appears to be the pinnacle of 10 years of research, a vast understanding still needs to be sought by scientists and engineers in relation to the modelling of wastewater quality. A main conclusion is drawn that these models can only ever be calibrated, but never truly verified and therefore are of little practical use to engineers attempting to solve wastewater problems within time and budgetary constraints.

    Information is presented on the way in which the public perceive water quality. This is shown to be based on the presence of land derived refuse within the watercourse corridor. Two of the urban watercourses studied, while being of low amenity value to those interviewed, were biochemically sound and were only judged unsatisfactory based on bankside refuse.

    An approach is presented based on historical rainfall and regression analysis to determine the level of service afforded by sewerage systems in terms of flooding. It is recommended that this approach be utilised to identify the true flooding performance of catchments as opposed to the common practice of design storms.
    Date of AwardSep 1997
    Original languageEnglish
    SponsorsNorth of Scotland Water Authority
    SupervisorDavid Blackwood (Supervisor) & Chris Jeffries (Supervisor)

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